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Журнальные статьи

1. Abraham M.H. 100 years of chromatography - or is it 171? // J. Chromatogr. A. 2004. Vol. 1061, № 1. P. 113–114.

It is pointed out that the term 'chromatography' existed already before Tswett introduced it for the separation technique he described.

http://dx.doi.org/10.1016%2Fj.chroma.2004.10.060

2. Ali I. et al. Ionic Liquids in HPLC and CE: A Hope for Future // Crit. Rev. Anal. Chem. 2017. Vol. 47, № 4. P. 332–339.

The ionic liquids (ILs) are salts with melting points below 100 degrees C. These are called as ionic fluids, ionic melts, liquid electrolytes, fused salts, liquid salts, ionic glasses, designer solvents, green solvents and solvents of the future. These have a wide range of applications, including medical, pharmaceutical and chemical sciences. Nowadays, their use is increasing greatly in separation science, especially in chromatography and capillary electrophoresis due to their remarkable properties. The present article describes the importance of ILs in high-performance liquid chromatography and capillary electrophoresis. Efforts were also made to highlight the future expectations of ILs.

http://dx.doi.org/10.1080%2F10408347.2017.1294047

3. Andrade F.N. et al. Development of on-line molecularly imprinted solid phase extraction-liquid chromatography-mass spectrometry for triazine analysis in corn samples // Anal. Methods. 2016. Vol. 8, № 5. P. 1181–1186.

A highly selective method for the analysis of triazine herbicides in corn samples based on molecularly imprinted solid phase extraction (MISPE) has been developed. Molecularly imprinted polymers (MIPs) were synthesized by precipitation polymerization using atrazine as a template, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a crosslinker, and 2,2'-azobis-isobutrynitrile as an initiator. MISPE was developed for the on-line and automated enrichment of atrazine, simazine, terbutryn, simetryn and ametryn from corn sample extracts. High-performance liquid chromatography and time-of-flight mass spectrometry were used for the separation and confident determination of the herbicides. The limits of detection and quantitation of the proposed method were set to be 1.6-3.3 mu g kg(-1) and 5.0-10.0 mu g kg(-1). The method was successfully applied for the analysis of five types of corns and the recoveries of the triazines from the spiked samples ranged from 80.2 to 119.1%.

http://dx.doi.org/10.1039%2Fc5ay02986d

4. Arrua R.D., Causon T.J., Hilder E.F. Recent developments and future possibilities for polymer monoliths in separation science // The Analyst. 2012. Vol. 137, № 22. P. 5179–5189.

Within recent years there has been an increase in research focused on the design and application of organic polymer monoliths in all areas of separation science. This is largely driven by the theoretical and practical benefits that these materials should be able to provide, particularly in terms of improved biocompatibility and high permeability. This review summarises recent new developments in this field with a focus on new approaches to the design and synthesis of polymeric monolithic materials for analytical separation science. This includes the use of alternative synthetic methodologies such as the development of hyper-crosslinked monoliths, preparation of hybrid materials and incorporation of nanostructures in the polymeric scaffold. New and developing approaches for the structural characterisation of monolithic columns are also included. Finally, we critically discuss the current chromatographic performances achieved with this column technology as well as where future developments in this field may be directed.

http://dx.doi.org/10.1039%2Fc2an35804b

5. Buszewski B., Bolonca T. 19th International Symposium on Separation Science: New Achievements in Chromatography // Chromatographia. 2014. Vol. 77, № 15–16. P. 981–983.

In September 2013, analysts/chromatographers met to discuss developments that have taken place in the theory and practice of separation methods. The theme of the meeting of this, the 19th ISC was New Achievements in Chromatography. It was held from the 25th to the 28th of September in the hotel complex, Valamar Diamant in Porec, Croatia (Figs. 1, 2). The meeting was organized by the Central European Group for Separation Sciences (CEGSS) and the Croatian Society of Chemical Engineers, Section for Chromatography, under the auspices of the European Society for Separation Science, to facilitate the exchange of experience in the field of chromatography and related techniques such as electrically driven methods. It encompassed all aspects, taking into account sample preparation, the use of chemometric techniques in modeling, visualization of the separation process, new system solutions and legislation.

http://dx.doi.org/10.1007%2Fs10337-014-2704-y

6. Cheong W.J. et al. Comprehensive overview of recent preparation and application trends of various open tubular capillary columns in separation science // Journal of Chromatography A. 2013. Vol. 1308. P. 1–24.

Open tubular (OT) capillary columns have been increasingly used in a variety of fields of separation science such as CEC, LC, and SPE. Especially their application in CEC has attracted a lot of attention for their outstanding separation performance. Various forms of OT stationary phase materials have been employed such as in-situ prepared polymers, molecular imprinted polymers (MIPs), brush ligands, host ligands, block copolymers, aptamers, carbon nanotubes, polysaccharides, proteins, tentacles, nanoparticles, monoliths, and polyelectrolyte multi-layers. They have been prepared either in the chemically bound format or physically adsorbed format. Sol-gel technologies and nanoparticles have been sometimes involved in their preparation. There have been also some unique miscellaneous studies, for example, adopting preferentially adsorbed mobile phase components as stationary phases. In this review, recent progresses since mostly 2007 will be critically discussed in detail with some summarized descriptions for the work before the date.

http://dx.doi.org/10.1016%2Fj.chroma.2013.07.107

7. Cheong W.J., Yang S.H., Ali F. Molecular imprinted polymers for separation science: A review of reviews // Journal of Separation Science. 2013. Vol. 36, № 3. P. 609–628.

Molecular imprinted polymer is an artificial receptor made by imprinting molecules of a template in a polymer matrix followed by removing the template molecules via thorough washing to give the permanent template grooves. They show favored affinity to the template molecule compared to other molecules, and this property is the basic driving force for such diverse application of this techniques. Such techniques have been increasingly employed in a wide scope of applications such as chromatography, sample pretreatment, purification, catalysts, sensors, and drug delivery, etc., mostly in bioanalytical areas. A major part of them is related to development of new stationary phases and their application in chromatography and sample pretreatment. Embodiments of molecular imprinted polymer materials have been carried out in a variety of forms such as irregularly ground particles, regular spherical particles, nanoparticles, monoliths in a stainless steel or capillary column, open tubular layers in capillaries, surface attached thin layers, membranes, and composites, etc. There have been numerous review articles on molecular imprinted polymer issues. In this special review, the reviews in recent ca. 10 years will be categorized into several subgroups according to specified topics in separation science, and each review in each subgroup will be introduced in the order of date with brief summaries and comments on new developments and different scopes of prospects. Brief summaries of each categories and conclusive future perspectives are also given.

http://dx.doi.org/10.1002%2Fjssc.201200784

8. Choudhury S., White B., Connolly D. Supermacroporous polyHIPE and cryogel monolithic materials as stationary phases in separation science: A review // Analytical Methods. 2015. Vol. 7, № 17. P. 6967–6982.

With their unique supermacroporous architecture, polyHIPEs (high internal phase emulsions) and cryogels have huge potential as analytical separation stationary phases. Due to their fully interconnected pore structure, mass transfer occurs predominantly via convection, potentially allowing for enhanced chromatographic performance. Additionally their surface functionalities can be tailored by modification of substrates both during and post fabrication. Their surface area is typically lower than comparable particulate stationary phases and problems with their rigidity persist. For these reasons, apart from their applications for large biomolecule analysis, the potential of cryogel and polyHIPE materials as separation phases in separation science have not been extensively realised. However, multiple strategies exist to overcome these limitations, potentially enabling the application of cryogels and polyHIPEs for a diverse range of separations. Current applications, such as chelation resins, which demonstrate the diverse interaction modes of both supermacroporous substrates, and applications of both substrates in analytical separations are considered in this review. Additionally the limitations of these technologies are explored, and strategies to overcome these limitations and further develop these monolithic phases for analytical separations are presented.

http://dx.doi.org/10.1039%2Fc5ay01193k

9. U54212
Ciminiello P. et al. High Resolution LC-MSn Fragmentation Pattern of Palytoxin as Template to Gain New Insights into Ovatoxin-a Structure. The Key Role of Calcium in MS Behavior of Palytoxins // J. Am. Soc. Mass Spectrom. 2012. Vol. 23, № 5. P. 952–963.

Palytoxin is a potent marine toxin and one of the most complex natural compounds ever described. A number of compounds identified as palytoxin congeners (e.g., ovatoxins, mascarenotoxins, ostreocins, etc.) have not been yet structurally elucidated due to lack of pure material in quantities sufficient to an NMR-based structural investigation. In this study, the complex fragmentation pattern of palytoxin in its positive high resolution liquid chromatography tandem mass spectra (HR LC-MSn) was interpreted. Under the used conditions, the molecule underwent fragmentation at many sites of its backbone, and a large number of diagnostic fragment ions were identified. The natural product itself was used with no need for derivatization. Interestingly, most of the fragments contained calcium in their elemental formula. Evidence for palytoxin tendency to form adduct ions with calcium and other divalent cations in its mass spectra was obtained. Fragmentation pattern of palytoxin was used as template to gain detailed structural information on ovatoxin-a, the main toxin produced by Ostreopsis ovata, (observe correct font) a benthic dinoflagellate that currently represents the major harmful algal bloom threat in the Mediterranean area. Either the regions or the specific sites where ovatoxin-a and palytoxin structurally differ have been identified.

http://dx.doi.org/10.1007%2Fs13361-012-0345-7

10. U54212
Ciminiello P. et al. High Resolution LC-MSn Fragmentation Pattern of Palytoxin as Template to Gain New Insights into Ovatoxin-a Structure. The Key Role of Calcium in MS Behavior of Palytoxins // J. Am. Soc. Mass Spectrom. 2012. Vol. 23, № 5. P. 952–963.

Palytoxin is a potent marine toxin and one of the most complex natural compounds ever described. A number of compounds identified as palytoxin congeners (e.g., ovatoxins, mascarenotoxins, ostreocins, etc.) have not been yet structurally elucidated due to lack of pure material in quantities sufficient to an NMR-based structural investigation. In this study, the complex fragmentation pattern of palytoxin in its positive high resolution liquid chromatography tandem mass spectra (HR LC-MSn) was interpreted. Under the used conditions, the molecule underwent fragmentation at many sites of its backbone, and a large number of diagnostic fragment ions were identified. The natural product itself was used with no need for derivatization. Interestingly, most of the fragments contained calcium in their elemental formula. Evidence for palytoxin tendency to form adduct ions with calcium and other divalent cations in its mass spectra was obtained. Fragmentation pattern of palytoxin was used as template to gain detailed structural information on ovatoxin-a, the main toxin produced by Ostreopsis ovata, (observe correct font) a benthic dinoflagellate that currently represents the major harmful algal bloom threat in the Mediterranean area. Either the regions or the specific sites where ovatoxin-a and palytoxin structurally differ have been identified.

http://dx.doi.org/10.1007%2Fs13361-012-0345-7

11. U54212
Creese A.J. et al. Probing the Complementarity of FAIMS and Strong Cation Exchange Chromatography in Shotgun Proteomics // J. Am. Soc. Mass Spectrom. 2013. Vol. 24, № 3. P. 431–443.

High field asymmetric waveform ion mobility spectrometry (FAIMS), also known as differential ion mobility spectrometry, coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS) offers benefits for the analysis of complex proteomics samples. Advantages include increased dynamic range, increased signal-to-noise, and reduced interference from ions of similar m/z. FAIMS also separates isomers and positional variants. An alternative, and more established, method of reducing sample complexity is prefractionation by use of strong cation exchange chromatography. Here, we have compared SCX-LC-MS/MS with LC-FAIMS-MS/MS for the identification of peptides and proteins from whole cell lysates from the breast carcinoma SUM52 cell line. Two FAIMS approaches are considered: (1) multiple compensation voltages within a single LC-MS/MS analysis (internal stepping) and (2) repeat LC-MS/MS analyses at different and fixed compensation voltages (external stepping). We also consider the consequence of the fragmentation method (electron transfer dissociation or collision-induced dissociation) on the workflow performance. The external stepping approach resulted in a greater number of protein and peptide identifications than the internal stepping approach for both ETD and CID MS/MS, suggesting that this should be the method of choice for FAIMS proteomics experiments. The overlap in protein identifications from the SCX method and the external FAIMS method was ~25 % for both ETD and CID, and for peptides was less than 20 %. The lack of overlap between FAIMS and SCX highlights the complementarity of the two techniques. Charge state analysis of the peptide assignments showed that the FAIMS approach identified a much greater proportion of triply-charged ions.

http://dx.doi.org/10.1007%2Fs13361-012-0544-2

12. U54212
Creese A.J. et al. Probing the Complementarity of FAIMS and Strong Cation Exchange Chromatography in Shotgun Proteomics // J. Am. Soc. Mass Spectrom. 2013. Vol. 24, № 3. P. 431–443.

High field asymmetric waveform ion mobility spectrometry (FAIMS), also known as differential ion mobility spectrometry, coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS) offers benefits for the analysis of complex proteomics samples. Advantages include increased dynamic range, increased signal-to-noise, and reduced interference from ions of similar m/z. FAIMS also separates isomers and positional variants. An alternative, and more established, method of reducing sample complexity is prefractionation by use of strong cation exchange chromatography. Here, we have compared SCX-LC-MS/MS with LC-FAIMS-MS/MS for the identification of peptides and proteins from whole cell lysates from the breast carcinoma SUM52 cell line. Two FAIMS approaches are considered: (1) multiple compensation voltages within a single LC-MS/MS analysis (internal stepping) and (2) repeat LC-MS/MS analyses at different and fixed compensation voltages (external stepping). We also consider the consequence of the fragmentation method (electron transfer dissociation or collision-induced dissociation) on the workflow performance. The external stepping approach resulted in a greater number of protein and peptide identifications than the internal stepping approach for both ETD and CID MS/MS, suggesting that this should be the method of choice for FAIMS proteomics experiments. The overlap in protein identifications from the SCX method and the external FAIMS method was ~25 % for both ETD and CID, and for peptides was less than 20 %. The lack of overlap between FAIMS and SCX highlights the complementarity of the two techniques. Charge state analysis of the peptide assignments showed that the FAIMS approach identified a much greater proportion of triply-charged ions.

http://dx.doi.org/10.1007%2Fs13361-012-0544-2

13. U5177X
Dai S.Y., Herrman T.J. Evaluation of two liquid chromatography/tandem mass spectrometry platforms for quantification of monensin in animal feed and milk // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 10. P. 1431–1438.

Monensin is an anticoccidial drug that has been used as an additive in medicated feed. The United States Food and Drug Administration (USFDA) has included monensin in the national surveillance schemes for residues in foodstuff. In this study, two simple, selective and rapid methods were developed to determine monensin content in animal feed and milk. The methods enabled the detection of monensin residues as low as 1 ppb. Moreover, the two methods were used as models to compare two common liquid chromatography/tandem mass spectrometry (LC/MS/MS) platforms; an LC linear ion trap (LC/LIT) and an LC triple quadrupole (LC/QqQ). The two instrument platforms were evaluated for their matrix effect dependence, precision and accuracy. The LC/QqQ presented a lower limit of detection and limit of quantitation (LOD and LOQ) and showed less matrix dependence as compared to the LC/LIT. The LC/QqQ instrument also demonstrated a better intermediate precision. For example, the intermediate precision standard deviation calculated for 27 analyses across three days was 4% and 11% for LC/QqQ and LC/LIT, respectively. Overall, the LC/QqQ represents a better choice for analysis of monensin with respect to LOD, LOQ, matrix interference and precision.

http://dx.doi.org/10.1002%2Frcm.4533

14. U5177X
Dai S.Y., Herrman T.J. Evaluation of two liquid chromatography/tandem mass spectrometry platforms for quantification of monensin in animal feed and milk // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 10. P. 1431–1438.

Monensin is an anticoccidial drug that has been used as an additive in medicated feed. The United States Food and Drug Administration (USFDA) has included monensin in the national surveillance schemes for residues in foodstuff. In this study, two simple, selective and rapid methods were developed to determine monensin content in animal feed and milk. The methods enabled the detection of monensin residues as low as 1 ppb. Moreover, the two methods were used as models to compare two common liquid chromatography/tandem mass spectrometry (LC/MS/MS) platforms; an LC linear ion trap (LC/LIT) and an LC triple quadrupole (LC/QqQ). The two instrument platforms were evaluated for their matrix effect dependence, precision and accuracy. The LC/QqQ presented a lower limit of detection and limit of quantitation (LOD and LOQ) and showed less matrix dependence as compared to the LC/LIT. The LC/QqQ instrument also demonstrated a better intermediate precision. For example, the intermediate precision standard deviation calculated for 27 analyses across three days was 4% and 11% for LC/QqQ and LC/LIT, respectively. Overall, the LC/QqQ represents a better choice for analysis of monensin with respect to LOD, LOQ, matrix interference and precision.

http://dx.doi.org/10.1002%2Frcm.4533

15. U01982
Dai X., Kramer-Tremblay S. Five-Column Chromatography Separation for Simultaneous Determination of Hard-to-Detect Radionuclides in Water and Swipe Samples // Anal. Chem. 2014. Vol. 86, № 11. P. 5441–5447.

There is a growing demand for the rapid determination of hard-to-detect radionuclides in environmental and biological samples for environmental monitoring, radiological protection, and nuclear forensic reasons. A new method using five-column chromatography separation has been developed for the simultaneous determination of Pu, Np, Th, U, Am, Cm, Pm, Y, and Sr isotopes, as well as iron-55, by inductively coupled mass spectrometry (ICPMS), ? spectrometry, Cerenkov and liquid scintillation (LS) counting. Spiked swipe and water samples as well as proficient testing water standards were analyzed to validate the separation procedure, and the results are in good agreement with the expected values. The method provides quick sample turnaround time and high analysis throughput with low analysis cost. The flexibility of the method also allows for its easy adaptation to various emergency and routine radioassays.

http://dx.doi.org/10.1021%2Fac500572g

16. U01982
Dai X., Kramer-Tremblay S. Five-Column Chromatography Separation for Simultaneous Determination of Hard-to-Detect Radionuclides in Water and Swipe Samples // Anal. Chem. 2014. Vol. 86, № 11. P. 5441–5447.

There is a growing demand for the rapid determination of hard-to-detect radionuclides in environmental and biological samples for environmental monitoring, radiological protection, and nuclear forensic reasons. A new method using five-column chromatography separation has been developed for the simultaneous determination of Pu, Np, Th, U, Am, Cm, Pm, Y, and Sr isotopes, as well as iron-55, by inductively coupled mass spectrometry (ICPMS), ? spectrometry, Cerenkov and liquid scintillation (LS) counting. Spiked swipe and water samples as well as proficient testing water standards were analyzed to validate the separation procedure, and the results are in good agreement with the expected values. The method provides quick sample turnaround time and high analysis throughput with low analysis cost. The flexibility of the method also allows for its easy adaptation to various emergency and routine radioassays.

http://dx.doi.org/10.1021%2Fac500572g

17. U01982
Daly C.E. et al. Qualitative and Quantitative Characterization of Plasma Proteins When Incorporating Traveling Wave Ion Mobility into a Liquid Chromatography–Mass Spectrometry Workflow for Biomarker Discovery: Use of Product Ion Quantitation As an Alternative Data Analysis Tool for Label Free Quantitation // Anal. Chem. 2014. Vol. 86, № 4. P. 1972–1979.

Discovery of protein biomarkers in clinical samples necessitates significant prefractionation prior to liquid chromatography–mass spectrometry (LC–MS) analysis. Integrating traveling wave ion mobility spectrometry (TWIMS) enables in-line gas phase separation which when coupled with nanoflow liquid chromatography and data independent acquisition tandem mass spectrometry, confers significant advantages to the discovery of protein biomarkers by improving separation and inherent sensitivity. Incorporation of TWIMS leads to a packet of concentrated ions which ultimately provides a significant improvement in sensitivity. As a consequence of ion packeting, when present at high concentrations, accurate quantitation of proteins can be affected due to detector saturation effects. Human plasma was analyzed in triplicate using liquid-chromatography data independent acquisition mass spectrometry (LC-DIA-MS) and using liquid-chromatography ion-mobility data independent acquisition mass spectrometry (LC-IM-DIA-MS). The inclusion of TWIMS was assessed for the effect on sample throughput, data integrity, confidence of protein and peptide identification, and dynamic range. The number of identified proteins is significantly increased by an average of 84% while both the precursor and product mass accuracies are maintained between the modalities. Sample dynamic range is also maintained while quantitation is achieved for all but the most abundant proteins by incorporating a novel data interpretation method that allows accurate quantitation to occur. This additional separation is all achieved within a workflow with no discernible deleterious effect on throughput. Consequently, TWIMS greatly enhances proteome coverage and can be reliably used for quantification when using an alternative product ion quantification strategy. Using TWIMS in biomarker discovery in human plasma is thus recommended.

http://dx.doi.org/10.1021%2Fac403901t

18. U01982
Daly C.E. et al. Qualitative and Quantitative Characterization of Plasma Proteins When Incorporating Traveling Wave Ion Mobility into a Liquid Chromatography–Mass Spectrometry Workflow for Biomarker Discovery: Use of Product Ion Quantitation As an Alternative Data Analysis Tool for Label Free Quantitation // Anal. Chem. 2014. Vol. 86, № 4. P. 1972–1979.

Discovery of protein biomarkers in clinical samples necessitates significant prefractionation prior to liquid chromatography–mass spectrometry (LC–MS) analysis. Integrating traveling wave ion mobility spectrometry (TWIMS) enables in-line gas phase separation which when coupled with nanoflow liquid chromatography and data independent acquisition tandem mass spectrometry, confers significant advantages to the discovery of protein biomarkers by improving separation and inherent sensitivity. Incorporation of TWIMS leads to a packet of concentrated ions which ultimately provides a significant improvement in sensitivity. As a consequence of ion packeting, when present at high concentrations, accurate quantitation of proteins can be affected due to detector saturation effects. Human plasma was analyzed in triplicate using liquid-chromatography data independent acquisition mass spectrometry (LC-DIA-MS) and using liquid-chromatography ion-mobility data independent acquisition mass spectrometry (LC-IM-DIA-MS). The inclusion of TWIMS was assessed for the effect on sample throughput, data integrity, confidence of protein and peptide identification, and dynamic range. The number of identified proteins is significantly increased by an average of 84% while both the precursor and product mass accuracies are maintained between the modalities. Sample dynamic range is also maintained while quantitation is achieved for all but the most abundant proteins by incorporating a novel data interpretation method that allows accurate quantitation to occur. This additional separation is all achieved within a workflow with no discernible deleterious effect on throughput. Consequently, TWIMS greatly enhances proteome coverage and can be reliably used for quantification when using an alternative product ion quantification strategy. Using TWIMS in biomarker discovery in human plasma is thus recommended.

http://dx.doi.org/10.1021%2Fac403901t

19. U5177X
De Troyer I. et al. Stable isotope analysis of dissolved organic carbon in soil solutions using a catalytic combustion total organic carbon analyzer-isotope ratio mass spectrometer with a cryofocusing interface // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 3. P. 365–374.

Stable carbon isotopes are a powerful tool to assess the origin and dynamics of carbon in soils. However, direct analysis of the 13C/12C ratio in the dissolved organic carbon (DOC) pool has proved to be difficult. Recently, several systems have been developed to measure isotope ratios in DOC by coupling a total organic carbon (TOC) analyzer with an isotope ratio mass spectrometer. However these systems were designed for the analysis of fresh and marine water and no results for soil solutions or 13C-enriched samples have been reported. Because we mainly deal with soil solutions in which the difficult to oxidize humic and fulvic acids are the predominant carbon-containing components, we preferred to use thermal catalytic oxidation to convert DOC into CO2. We therefore coupled a high-temperature combustion TOC analyzer with an isotope ratio mass spectrometer, by trapping and focusing the CO2 cryogenically between the instruments. The analytical performance was tested by measuring solutions of compounds varying in the ease with which they can be oxidized. Samples with DOC concentrations between 1 and 100?mg C/L could be analyzed with good precision (standard deviation (SD) ?0.6‰), acceptable accuracy, good linearity (overall SD?=?1‰) and without significant memory effects. In a 13C-tracer experiment, we observed that mixing plant residues with soil caused a release of plant-derived DOC, which was degraded or sorbed during incubation. Based on these results, we are confident that this approach can become a relatively simple alternative method for the measurement of the 13C/12C ratio of DOC in soil solutions.

http://dx.doi.org/10.1002%2Frcm.4403

20. U5177X
De Troyer I. et al. Stable isotope analysis of dissolved organic carbon in soil solutions using a catalytic combustion total organic carbon analyzer-isotope ratio mass spectrometer with a cryofocusing interface // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 3. P. 365–374.

Stable carbon isotopes are a powerful tool to assess the origin and dynamics of carbon in soils. However, direct analysis of the 13C/12C ratio in the dissolved organic carbon (DOC) pool has proved to be difficult. Recently, several systems have been developed to measure isotope ratios in DOC by coupling a total organic carbon (TOC) analyzer with an isotope ratio mass spectrometer. However these systems were designed for the analysis of fresh and marine water and no results for soil solutions or 13C-enriched samples have been reported. Because we mainly deal with soil solutions in which the difficult to oxidize humic and fulvic acids are the predominant carbon-containing components, we preferred to use thermal catalytic oxidation to convert DOC into CO2. We therefore coupled a high-temperature combustion TOC analyzer with an isotope ratio mass spectrometer, by trapping and focusing the CO2 cryogenically between the instruments. The analytical performance was tested by measuring solutions of compounds varying in the ease with which they can be oxidized. Samples with DOC concentrations between 1 and 100?mg C/L could be analyzed with good precision (standard deviation (SD) ?0.6‰), acceptable accuracy, good linearity (overall SD?=?1‰) and without significant memory effects. In a 13C-tracer experiment, we observed that mixing plant residues with soil caused a release of plant-derived DOC, which was degraded or sorbed during incubation. Based on these results, we are confident that this approach can become a relatively simple alternative method for the measurement of the 13C/12C ratio of DOC in soil solutions.

http://dx.doi.org/10.1002%2Frcm.4403

21. Declerck S., Vander Heyden Y., Mangelings D. Enantioseparations of pharmaceuticals with capillary electrochromatography: A review // J. Pharm. Biomed. Anal. 2016. Vol. 130. P. 81–99.

The chiral separation of pharmaceuticals is one of the major research topics in the pharmaceutical industry. Chromatographic techniques are most frequently used in this context. Separations in capillary electrochromatography (CEC) are an alternative and achieved by chromatographic retention and electrophoretic mobility principles. As a result, CEC is characterized by a high selectivity and efficiency. The limited number of stationary phases specifically developed for CEC, the low number of commercially available CEC columns, the fits to maintain the stationary phase, which forms fragile spots in the columns, and the limited column robustness and reproducibility, make CEC not very attractive for industrial application. However, CEC is still applied and studied in the academic field. This review discusses the enantioseparation of drugs in CEC published during the last four years, with a critical view on the reproducibility and the practical utility of these applications.

http://dx.doi.org/10.1016%2Fj.jpba.2016.04.024

22. U01982
Dunand M. et al. High-Throughput and Sensitive Quantitation of Plasma Catecholamines by Ultraperformance Liquid Chromatography–Tandem Mass Spectrometry Using a Solid Phase Microwell Extraction Plate // Anal. Chem. 2013. Vol. 85, № 7. P. 3539–3544.

Plasma catecholamines provide a reliable biomarker of sympathetic activity. The low circulating concentrations of catecholamines and analytical interferences require tedious sample preparation and long chromatographic runs to ensure their accurate quantification by HPLC with electrochemical detection. Published or commercially available methods relying on solid phase extraction technology lack sensitivity or require derivatization of catecholamine by hazardous reagents prior to tandem mass spectrometry (MS) analysis. Here, we manufactured a novel 96-well microplate device specifically designed to extract plasma catecholamines prior to their quantification by a new and highly sensitive ultraperformance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method. Processing time, which included sample purification on activated aluminum oxide and elution, is less than 1 h per 96-well microplate. The UPLC–MS/MS analysis run time is 2.0 min per sample. This UPLC–MS/MS method does not require a derivatization step, reduces the turnaround time by 10-fold compared to conventional methods used for routine application, and allows catecholamine quantification in reduced plasma sample volumes (50–250 ?L, e.g., from children and mice).

http://dx.doi.org/10.1021%2Fac4004584

23. U01982
Dunand M. et al. High-Throughput and Sensitive Quantitation of Plasma Catecholamines by Ultraperformance Liquid Chromatography–Tandem Mass Spectrometry Using a Solid Phase Microwell Extraction Plate // Anal. Chem. 2013. Vol. 85, № 7. P. 3539–3544.

Plasma catecholamines provide a reliable biomarker of sympathetic activity. The low circulating concentrations of catecholamines and analytical interferences require tedious sample preparation and long chromatographic runs to ensure their accurate quantification by HPLC with electrochemical detection. Published or commercially available methods relying on solid phase extraction technology lack sensitivity or require derivatization of catecholamine by hazardous reagents prior to tandem mass spectrometry (MS) analysis. Here, we manufactured a novel 96-well microplate device specifically designed to extract plasma catecholamines prior to their quantification by a new and highly sensitive ultraperformance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) method. Processing time, which included sample purification on activated aluminum oxide and elution, is less than 1 h per 96-well microplate. The UPLC–MS/MS analysis run time is 2.0 min per sample. This UPLC–MS/MS method does not require a derivatization step, reduces the turnaround time by 10-fold compared to conventional methods used for routine application, and allows catecholamine quantification in reduced plasma sample volumes (50–250 ?L, e.g., from children and mice).

http://dx.doi.org/10.1021%2Fac4004584

24. Engelhardt H. One century of liquid chromatography from Tswett’s columns to modem high speed and high performance separations // J. Chromatogr. B. 2004. Vol. 800, № 1–2. P. 3–6.

A personal view on the history of liquid chromatography has been given, starting with my personal experience with paper chromatography dating back to 1958. If I have forgotten the contribution of a colleague it was not on purpose, but limitations of memory and space may be responsible. For those further interested in the history of chromatography, the following monographs should be referred to .

http://dx.doi.org/10.1016%2Fj.jchromb.2003.09.064

25. U5177X
Ferreres F. et al. First report of non-coloured flavonoids in Echium plantagineum bee pollen: differentiation of isomers by liquid chromatography/ion trap mass spectrometry // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 6. P. 801–806.

Apicultural products have been widely used in diet complements as well as in phytotherapy. Bee pollen from Echium plantagineum was analysed by high-performance liquid chromatography/photodiode-array detection coupled to ion trap mass spectrometry (HPLC-PAD-MSn) with an electrospray ionisation interface. The structures have been determined by the study of the ion mass fragmentation, which characterises the interglycosidic linkage in glycosylated flavonoids and differentiates positional isomers. Twelve non-coloured flavonoids were characterised, being kaempferol-3-O-neohesperidoside the major compound, besides others in trace amounts. These include quercetin, kaempferol and isorhamnetin glycosides, with several of them being isomers. Acetylated derivatives are also described. This is the first time that non-coloured flavonoids are reported from this pollen, with MS fragmentation proving to be most useful in the elucidation of isomeric structures.

http://dx.doi.org/10.1002%2Frcm.4454

26. U5177X
Ferreres F. et al. First report of non-coloured flavonoids in Echium plantagineum bee pollen: differentiation of isomers by liquid chromatography/ion trap mass spectrometry // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 6. P. 801–806.

Apicultural products have been widely used in diet complements as well as in phytotherapy. Bee pollen from Echium plantagineum was analysed by high-performance liquid chromatography/photodiode-array detection coupled to ion trap mass spectrometry (HPLC-PAD-MSn) with an electrospray ionisation interface. The structures have been determined by the study of the ion mass fragmentation, which characterises the interglycosidic linkage in glycosylated flavonoids and differentiates positional isomers. Twelve non-coloured flavonoids were characterised, being kaempferol-3-O-neohesperidoside the major compound, besides others in trace amounts. These include quercetin, kaempferol and isorhamnetin glycosides, with several of them being isomers. Acetylated derivatives are also described. This is the first time that non-coloured flavonoids are reported from this pollen, with MS fragmentation proving to be most useful in the elucidation of isomeric structures.

http://dx.doi.org/10.1002%2Frcm.4454

27. U01982
Franze B., Engelhard C. Fast Separation, Characterization, and Speciation of Gold and Silver Nanoparticles and Their Ionic Counterparts with Micellar Electrokinetic Chromatography Coupled to ICP-MS // Anal. Chem. 2014. Vol. 86, № 12. P. 5713–5720.

In this study, a method for separation, size characterization, and speciation of gold and silver nanoparticles was developed through the use of micellar electrokinetic chromatography (MEKC) coupled to inductively coupled plasma-mass spectrometry (ICP-MS) for the first time. Figures of merit in this proof-of-principle study include peak area precision of 4–6%, stable migration times (1.4% with internal standard), and capillary recoveries on the order of 72–100% depending on species and nanoparticle size, respectively. Detection limits are currently in the sub-microgram per liter range. For example, a total of 1500 50-nm-sized gold nanoparticles were successfully detected. After careful optimization, MEKC-ICP-MS was used to separate engineered nanoparticles (ENPs) of different composition. Speciation analysis of ENPs and free metal ions in solution was feasible using a complexing agent (penicillamine). Gold speciation analysis of a dietary supplement, which contained approximately 6-nm-sized gold nanoparticles, was demonstrated.

http://dx.doi.org/10.1021%2Fac403998e

28. U01982
Franze B., Engelhard C. Fast Separation, Characterization, and Speciation of Gold and Silver Nanoparticles and Their Ionic Counterparts with Micellar Electrokinetic Chromatography Coupled to ICP-MS // Anal. Chem. 2014. Vol. 86, № 12. P. 5713–5720.

In this study, a method for separation, size characterization, and speciation of gold and silver nanoparticles was developed through the use of micellar electrokinetic chromatography (MEKC) coupled to inductively coupled plasma-mass spectrometry (ICP-MS) for the first time. Figures of merit in this proof-of-principle study include peak area precision of 4–6%, stable migration times (1.4% with internal standard), and capillary recoveries on the order of 72–100% depending on species and nanoparticle size, respectively. Detection limits are currently in the sub-microgram per liter range. For example, a total of 1500 50-nm-sized gold nanoparticles were successfully detected. After careful optimization, MEKC-ICP-MS was used to separate engineered nanoparticles (ENPs) of different composition. Speciation analysis of ENPs and free metal ions in solution was feasible using a complexing agent (penicillamine). Gold speciation analysis of a dietary supplement, which contained approximately 6-nm-sized gold nanoparticles, was demonstrated.

http://dx.doi.org/10.1021%2Fac403998e

29. U01982
Fu C., Khaledi M.G. Characterization and Classification of Pseudo-Stationary Phases in Micellar Electrokinetic Chromatography Using Chemometric Methods // Anal. Chem. 2014. Vol. 86, № 5. P. 2371–2379.

Two types of chemometric methods, principal component analysis (PCA) and cluster analysis, are employed to characterize and classify a total of 70 pseudostationary phases (54 distinct systems and 16 decoy systems) in micellar electrokinetic chromatography (MEKC). PCA excels at removing redundant information for micellar phase characterization and retaining principal determinants for phase classification. While PCA is useful in the characterization of micelle selectivities, it is ineffective in defining the grouping of micellar phases. Hierarchical clustering yields a complete dendrogram of cluster structures but provides only limited cluster characterizations. The combination of these two chemometric methods leads to a comprehensive interpretation of the micellar phase classification. Moreover, the k-means analysis can further discern subtle differences among those closely located micellar phases. All three chemometric methods result in similar classifications with respect to the similarities and differences of the 70 micelle systems investigated. These systems are categorized into 3 major clusters: fluoro-surfactants represent cluster I, identified as strong hydrogen bond donors and dipolar but weak hydrogen bond acceptors. Cluster II includes sulfonated acrylamide/acrylate copolymers and surfactants with trimethylammonium head groups, characterized by strong hydrophobicity (v) and weak hydrogen bond acidity (b). The last cluster consists of two subclusters: clusters III and IV. Cluster III includes siloxane-based polymeric micelles, exhibiting weak hydrophobicity and medium hydrogen bond acidity and basicity (a), and the cluster IV micellar systems are characterized by their strong hydrophobicity and medium hydrogen bond acidity and basicity but rather weak dipolarity. Cluster III differs from cluster IV by its slightly weaker hydrophobicity and hydrogen bond donating capability. The classification by chemometric methods is in good agreement with the classification by the micellar selectivity triangle (MST) (Fu, C.; Khaledi, M. G. J. Chromatogr., A 2009, 1216, 1891?1900).

http://dx.doi.org/10.1021%2Fac403231h

30. U01982
Fu C., Khaledi M.G. Characterization and Classification of Pseudo-Stationary Phases in Micellar Electrokinetic Chromatography Using Chemometric Methods // Anal. Chem. 2014. Vol. 86, № 5. P. 2371–2379.

Two types of chemometric methods, principal component analysis (PCA) and cluster analysis, are employed to characterize and classify a total of 70 pseudostationary phases (54 distinct systems and 16 decoy systems) in micellar electrokinetic chromatography (MEKC). PCA excels at removing redundant information for micellar phase characterization and retaining principal determinants for phase classification. While PCA is useful in the characterization of micelle selectivities, it is ineffective in defining the grouping of micellar phases. Hierarchical clustering yields a complete dendrogram of cluster structures but provides only limited cluster characterizations. The combination of these two chemometric methods leads to a comprehensive interpretation of the micellar phase classification. Moreover, the k-means analysis can further discern subtle differences among those closely located micellar phases. All three chemometric methods result in similar classifications with respect to the similarities and differences of the 70 micelle systems investigated. These systems are categorized into 3 major clusters: fluoro-surfactants represent cluster I, identified as strong hydrogen bond donors and dipolar but weak hydrogen bond acceptors. Cluster II includes sulfonated acrylamide/acrylate copolymers and surfactants with trimethylammonium head groups, characterized by strong hydrophobicity (v) and weak hydrogen bond acidity (b). The last cluster consists of two subclusters: clusters III and IV. Cluster III includes siloxane-based polymeric micelles, exhibiting weak hydrophobicity and medium hydrogen bond acidity and basicity (a), and the cluster IV micellar systems are characterized by their strong hydrophobicity and medium hydrogen bond acidity and basicity but rather weak dipolarity. Cluster III differs from cluster IV by its slightly weaker hydrophobicity and hydrogen bond donating capability. The classification by chemometric methods is in good agreement with the classification by the micellar selectivity triangle (MST) (Fu, C.; Khaledi, M. G. J. Chromatogr., A 2009, 1216, 1891?1900).

http://dx.doi.org/10.1021%2Fac403231h

31. U54212
Gao J. et al. HPLC/APCI Mass Spectrometry of Saturated and Unsaturated Hydrocarbons by Using Hydrocarbon Solvents as the APCI Reagent and HPLC Mobile Phase // J. Am. Soc. Mass Spectrom. 2012. Vol. 23, № 5. P. 816–822.

Saturated and unsaturated, linear, branched, and cyclic hydrocarbons, as well as polyaromatic and heteroaromatic hydrocarbons, were successfully ionized by atmospheric pressure chemical ionization (APCI) using small hydrocarbons as reagents in a linear quadrupole ion trap (LQIT) mass spectrometer. Pentane was proved to be the best reagent among the hydrocarbon reagents studied. This ionization method generated different types of abundant ions (i.e., [M + H]+, M+•, [M – H]+ and [M – 2H]+ •), with little or no fragmentation. The radical cations can be differentiated from the even-electron ions by using dimethyl disulfide, thus facilitating molecular weight (MW) determination. While some steroids and lignin monomer model compounds, such as androsterone and 4-hydroxy-3-methoxybenzaldehyde, also formed abundant M+• and [M + H]+ ions, this was not true for all of them. Analysis of two known mixtures as well as a base oil sample demonstrated that each component of the known mixtures could be observed and that a correct MW distribution was obtained for the base oil. The feasibility of using this ionization method on the chromatographic time scale was demonstrated by using high-performance liquid chromatography (HPLC) with hexane as the mobile phase (and APCI reagent) to separate an artificial mixture prior to mass spectrometric analysis.

http://dx.doi.org/10.1007%2Fs13361-012-0347-5

32. U54212
Gao J. et al. HPLC/APCI Mass Spectrometry of Saturated and Unsaturated Hydrocarbons by Using Hydrocarbon Solvents as the APCI Reagent and HPLC Mobile Phase // J. Am. Soc. Mass Spectrom. 2012. Vol. 23, № 5. P. 816–822.

Saturated and unsaturated, linear, branched, and cyclic hydrocarbons, as well as polyaromatic and heteroaromatic hydrocarbons, were successfully ionized by atmospheric pressure chemical ionization (APCI) using small hydrocarbons as reagents in a linear quadrupole ion trap (LQIT) mass spectrometer. Pentane was proved to be the best reagent among the hydrocarbon reagents studied. This ionization method generated different types of abundant ions (i.e., [M + H]+, M+•, [M – H]+ and [M – 2H]+ •), with little or no fragmentation. The radical cations can be differentiated from the even-electron ions by using dimethyl disulfide, thus facilitating molecular weight (MW) determination. While some steroids and lignin monomer model compounds, such as androsterone and 4-hydroxy-3-methoxybenzaldehyde, also formed abundant M+• and [M + H]+ ions, this was not true for all of them. Analysis of two known mixtures as well as a base oil sample demonstrated that each component of the known mixtures could be observed and that a correct MW distribution was obtained for the base oil. The feasibility of using this ionization method on the chromatographic time scale was demonstrated by using high-performance liquid chromatography (HPLC) with hexane as the mobile phase (and APCI reagent) to separate an artificial mixture prior to mass spectrometric analysis.

http://dx.doi.org/10.1007%2Fs13361-012-0347-5

33. Gezici O., Bayrakci M. Calixarene-engineered surfaces and separation science // J. Incl. Phenom. Macrocycl. Chem. 2015. Vol. 83, № 1–2. P. 1–18.

After their discovery, calixarenes have attracted the attention of many researchers from various disciplines. This group of supramolecules has an increasing popularity and this is most probably related with the flexibility of calixarene chemistry. Owing to their multifunctional character and stability, calixarenes became important precursors in separation science to derive new-type of sorbents or stationary phases. Immobilization of calixarenes to a suitable solid support (e.g. silica, synthetic polymers, magnetite nanoparticles, etc.) is a very popular concept being used for this purpose, and various immobilization methodologies have been proposed in the literature. In the present work, some state-of-the-art researches and developments published in the past are reviewed in a collective manner, and thus fundamentals of calixarene-immobilization and the application of the obtained materials in sorption and high performance liquid chromatography are represented.

http://dx.doi.org/10.1007%2Fs10847-015-0553-4

34. Greibrokk T. Molecular Imprinting in Separation Science // Journal of Separation Science. 2016. Vol. 39, № 5. P. 815–817.

Molecularly imprinted polymers (MIPs) are expected to exhibit high selec- tivity and high affinity towards a single compound or a class of compounds. In separation science , MIPs are used for the extraction and preconcentration of analytes or for the removal of unwanted contaminants. In addition, MIPs can also be used in assays, as sensors and as drug-release materials

ttp://dx.doi.org/10.1002/jssc.201670054

35. U01982
Gritti F., Guiochon G. Perspectives on the Evolution of the Column Efficiency in Liquid Chromatography // Anal. Chem. 2013. Vol. 85, № 6. P. 3017–3035.

When analyses of mixtures of small molecules are carried out at mobile phase velocities close to (for isocratic runs) or somewhat above (for gradient runs) the optimum velocity, the eddy diffusion term contributes to at least 75% of the band broadening. Future improvements in column performance may come only from a reduction of the eddy diffusion term. The classical models of axial dispersion of Gunn and Giddings are revisited and their predictions compared to recently reported eddy dispersion data obtained by solving numerically the Navier–Stokes equations and simulating advective-diffusive transport in the bulk region and in confined geometries of reconstructed and computer-generated random sphere packings. The Gunn model fails to describe these data. In contrast, the Giddings model succeeds, provided that his original guesses regarding the values of two parameters of his model are adjusted. Accurate measurements of real eddy dispersion data in modern high-pressure liquid chromatography (HPLC) columns were performed by applying a well established experimental protocol. Their results demonstrate that the other contribution to band broadening, sample dispersion in the homogeneous bulk region of these packed beds, accounts for less than 30% of the total eddy dispersion at velocities larger than the optimum velocity. This shows that the resolution power of modern HPLC columns is essentially controlled by wall and/or border layer trans-column eddy dispersion effects, depending on whether the column is radially equilibrated or not. Under a preasymptotic dispersion regime, the performance of short and wide HPLC columns is controlled by the border effects. As the bed aspect ratio (D/dp) increases, the column performance tends toward that of the infinite diameter column. Further improvement appears possible using radial segmentation of the outlet flow. Under an asymptotic dispersion regime, the reduced column plate height of long and thin HPLC columns is controlled by the wall effects and can be optimized only by improving the packing procedures, keeping as low as possible the bed aspect ratio and maximizing the transverse dispersion coefficient.

http://dx.doi.org/10.1021%2Fac3033307

36. U01982
Gritti F., Guiochon G. Perspectives on the Evolution of the Column Efficiency in Liquid Chromatography // Anal. Chem. 2013. Vol. 85, № 6. P. 3017–3035.

When analyses of mixtures of small molecules are carried out at mobile phase velocities close to (for isocratic runs) or somewhat above (for gradient runs) the optimum velocity, the eddy diffusion term contributes to at least 75% of the band broadening. Future improvements in column performance may come only from a reduction of the eddy diffusion term. The classical models of axial dispersion of Gunn and Giddings are revisited and their predictions compared to recently reported eddy dispersion data obtained by solving numerically the Navier–Stokes equations and simulating advective-diffusive transport in the bulk region and in confined geometries of reconstructed and computer-generated random sphere packings. The Gunn model fails to describe these data. In contrast, the Giddings model succeeds, provided that his original guesses regarding the values of two parameters of his model are adjusted. Accurate measurements of real eddy dispersion data in modern high-pressure liquid chromatography (HPLC) columns were performed by applying a well established experimental protocol. Their results demonstrate that the other contribution to band broadening, sample dispersion in the homogeneous bulk region of these packed beds, accounts for less than 30% of the total eddy dispersion at velocities larger than the optimum velocity. This shows that the resolution power of modern HPLC columns is essentially controlled by wall and/or border layer trans-column eddy dispersion effects, depending on whether the column is radially equilibrated or not. Under a preasymptotic dispersion regime, the performance of short and wide HPLC columns is controlled by the border effects. As the bed aspect ratio (D/dp) increases, the column performance tends toward that of the infinite diameter column. Further improvement appears possible using radial segmentation of the outlet flow. Under an asymptotic dispersion regime, the reduced column plate height of long and thin HPLC columns is controlled by the wall effects and can be optimized only by improving the packing procedures, keeping as low as possible the bed aspect ratio and maximizing the transverse dispersion coefficient.

http://dx.doi.org/10.1021%2Fac3033307

37. Guihen E. Nanoparticles in modern separation science // Trac-Trends Anal. Chem. 2013. Vol. 46. P. 1–14.

This review article covers the concepts and the theory behind using nanoparticles (NPs) in separation science. Recent examples show the use of NPs in capillary electrophoresis and electrochromatography. Specific examples involve the use of NPs in liquid, gas and ion chromatography, along with recent applications showing the use of NPs in microchip electrophoresis. Future trends and conclusions are also covered.

http://dx.doi.org/10.1016%2Fj.trac.2013.01.011

38. U01982
Hendricks P.I. et al. Autonomous in Situ Analysis and Real-Time Chemical Detection Using a Backpack Miniature Mass Spectrometer: Concept, Instrumentation Development, and Performance // Anal. Chem. 2014. Vol. 86, № 6. P. 2900–2908.

A major design objective of portable mass spectrometers is the ability to perform in situ chemical analysis on target samples in their native states in the undisturbed environment. The miniature instrument described here is fully contained in a wearable backpack (10 kg) with a geometry-independent low-temperature plasma (LTP) ion source integrated into a hand-held head unit (2 kg) to allow direct surface sampling and analysis. Detection of chemical warfare agent (CWA) simulants, illicit drugs, and explosives is demonstrated at nanogram levels directly from surfaces in near real time including those that have complex geometries, those that are heat-sensitive, and those bearing complex sample matrices. The instrument consumes an average of 65 W of power and can be operated autonomously under battery power for ca. 1.5 h, including the initial pump-down of the manifold. The maximum mass-to-charge ratio is 925 Th with mass resolution of 1–2 amu full width at half-maximun (fwhm) across the mass range. Multiple stages of tandem analysis can be performed to identify individual compounds in complex mixtures. Both positive and negative ion modes are available. A graphical user interface (GUI) is available for novice users to facilitate data acquisition and real-time spectral matching.

http://dx.doi.org/10.1021%2Fac403765x

39. U01982
Hendricks P.I. et al. Autonomous in Situ Analysis and Real-Time Chemical Detection Using a Backpack Miniature Mass Spectrometer: Concept, Instrumentation Development, and Performance // Anal. Chem. 2014. Vol. 86, № 6. P. 2900–2908.

A major design objective of portable mass spectrometers is the ability to perform in situ chemical analysis on target samples in their native states in the undisturbed environment. The miniature instrument described here is fully contained in a wearable backpack (10 kg) with a geometry-independent low-temperature plasma (LTP) ion source integrated into a hand-held head unit (2 kg) to allow direct surface sampling and analysis. Detection of chemical warfare agent (CWA) simulants, illicit drugs, and explosives is demonstrated at nanogram levels directly from surfaces in near real time including those that have complex geometries, those that are heat-sensitive, and those bearing complex sample matrices. The instrument consumes an average of 65 W of power and can be operated autonomously under battery power for ca. 1.5 h, including the initial pump-down of the manifold. The maximum mass-to-charge ratio is 925 Th with mass resolution of 1–2 amu full width at half-maximun (fwhm) across the mass range. Multiple stages of tandem analysis can be performed to identify individual compounds in complex mixtures. Both positive and negative ion modes are available. A graphical user interface (GUI) is available for novice users to facilitate data acquisition and real-time spectral matching.

http://dx.doi.org/10.1021%2Fac403765x

40. Herrera-Herrera A.V. et al. Carbon nanotubes applications in separation science: A review // Analytica Chimica Acta. 2012. Vol. 734. P. 1–30.

Due to the intensive and multidisciplinary research carried out during the last two decades on carbon nanotubes (CNTs), the scientific community understands nowadays much better the chemistry, structure and properties of these interesting materials. In fact, they have found their particular place in a wide number of application fields (nanotechnology, electronics, optics, medicine, etc.) among which Analytical Chemistry is becoming more and more important. The aim of this review is to provide an updated report of the most recent manuscripts (years 2009-2011) regarding the use of CNTs in Separation Science. In particular, the use of CNTs as solid-phase extraction and microextraction sorbents, as part of membranes as well as their use in chromatography and electrophoresis will be discussed and commented. Besides, although not as fully related to Separation Science as the previous techniques, the use of CNTs as laser desorption/ionization substrates has also been considered because of its importance in the field.

http://dx.doi.org/10.1016%2Fj.aca.2012.04.035

41. Ho W.S.W., Li K. Editorial overview: Separation engineering: Recent advances in separation science and technology // Curr. Opin. Chem. Eng. 2016. Vol. 12. P. VII–XI.

This themed issue consists of review articles covering topics in recent advances in electrospun nanofiber membranes for microfiltration, ultrafiltration, nanofiltration, reverse osmosis, membrane distillation and adsorption, graphene oxide membranes in fluid separations, adsorption in amine-functionalized sorbents for CO2 capture, anion-exchange membranes for fuel cells, Bruggeman correlation for analyzing transport phenomena in electrochemical systems, and uphill diffusion in fluid mixtures, electrolytes, alloys, glasses, and porous adsorbents.

http://dx.doi.org/10.1016%2Fj.coche.2016.05.001

42. U15769
Holler U. et al. Rapid determination of 25-hydroxy vitamin D3 in swine tissue using an isotope dilution HPLC-MS assay // Journal of Chromatography B. 2010. Vol. 878, № 13. P. 963–968.

A rapid method for quantification of 25-hydroxy vitamin D3 in different swine tissues based on isotope dilution HPLC-MS has been developed and validated. Six times deuterated analyte is used as internal standard. The method is fast and can be performed with only 1g sample. Sample preparation for kidney, liver, muscle and spleen requires only homogenisation and extraction with methanol. An additional enzymatic digest is required for skin, and clean-up of the extract by solid-phase extraction (SPE) is used for adipose tissue and skin. The lower limit of detection varies from 1ng/g (muscle) to 5ng/g (adipose and skin). The method has been successfully applied to various tissue samples of pigs fed for 119 days either 2000IU of vitamin D3 or 50?g of 25-hydroxy vitamin D3 per kg feed. For animals ingesting 25-OH-D3 supplements the highest tissue contents were observed in the skin (24.8±3.5ng/g), followed by kidney (14.2±1.5ng/g), liver and muscle (5.7±0.6ng/g). The 25-OH-D3 content in the skin was significantly higher in animals ingesting 2000IU/kg of vitamin D3 (39.5±13.4ng/g). Levels in selected tissues of some animals were below the lower limit of quantification. No measurable amounts of 25-OH-D3 were found in spleen, abdominal fat and subcutaneous fat of the animals of both groups as well as in the liver, kidney and muscle of the animals ingesting 2000IU/kg of vitamin D3.

http://dx.doi.org/10.1016%2Fj.jchromb.2010.02.026

43. Hong T. et al. Recent advances in the preparation and application of monolithic capillary columns in separation science // Anal. Chim. Acta. 2016. Vol. 931. P. 1–24.

Novel column technologies involving various materials and efficient reactions have been investigated for the fabrication of monolithic capillary columns in the field of analytical chemistry. In addition to the development of these miniaturized systems, a variety of microscale separation applications have achieved noteworthy results, providing a stepping stone for new types of chromatographic columns with improved efficiency and selectivity. Three novel strategies for the preparation of capillary monoliths, including ionic liquid-based approaches, nanoparticle-based approaches and "click chemistry", are highlighted in this review. Furthermore, we present the employment of state-of-the-art capillary monolithic stationary phases for enantioseparation, solid-phase microextraction, mixed-mode separation and immobilized enzyme reactors. The review concludes with recommendations for future studies and improvements in this field of research.

http://dx.doi.org/10.1016%2Fj.aca.2016.05.013

44. U15769
Jansen R.S. et al. Simultaneous quantification of emtricitabine and tenofovir nucleotides in peripheral blood mononuclear cells using weak anion-exchange liquid chromatography coupled with tandem mass spectrometry // Journal of Chromatography B. 2010. Vol. 878, № 7. P. 621–627.

Emtricitabine (FTC) and tenofovir (TFV) are widely used antiviral agents that require intracellular phosphorylation to become active. This article describes the development and validation of an assay for the simultaneous quantification of FTC mono-, di- and triphosphate (FTC-MP, -DP and -TP), TFV and TFV mono- and diphosphate (TFV-MP and -DP) in peripheral blood mononuclear cells. Reference compounds and internal standards were obtained by thermal degradation of FTC-TP, TFV-DP, stable isotope-labeled TFV-DP and stable isotope-labeled cytosine triphosphate. Cells were lysed in methanol:water (70:30, v/v) and the extracted nucleotides were analyzed using weak anion-exchange chromatography coupled with tandem mass spectrometry. Calibration ranges in PBMC lysate from 0.727 to 36.4, 1.33 to 66.4 and 1.29 to 64.6nM for FTC-MP, FTC-DP and FTC-TP and from 1.51 to 75.6, 1.54 to 77.2 and 2.54 to 127nM for TFV, TFV-MP and TFV-DP, respectively, were validated. Accuracies were within ?10.3 and 16.7% deviation at the lower limit of quantification at which the coefficients of variation were less than 18.2%. At the other tested levels accuracies were within ?14.3 and 9.81% deviation and the coefficients of variation lower than 14.7%. The stability of the compounds was assessed under various analytically relevant conditions. The method was successfully applied to clinical samples.

http://dx.doi.org/10.1016%2Fj.jchromb.2010.01.002

45. U15769
John H. et al. Simultaneous quantification of the organophosphorus pesticides dimethoate and omethoate in porcine plasma and urine by LC–ESI-MS/MS and flow-injection-ESI-MS/MS // Journal of Chromatography B. 2010. Vol. 878, № 17. P. 1234–1245.

Dimethoate is an organophosphorus toxicant used in agri- and horticulture as a systemic broad-spectrum insecticide. It also exhibits toxic activity towards mammalian organism provoked by catalytic desulfuration in the liver producing its oxon-derivative omethoate thus inhibiting acetylcholinesterase, initiating cholinergic crisis and ultimately leading to death by respiratory paralysis and cardiovascular collapse. Pharmaco- and toxicokinetic studies in animal models help to broaden basic understanding of medical intervention by antidotes and supportive care. Therefore, we developed and validated a LC–ESI-MS/MS method suitable for the simultaneous, selective, precise (RSDintra-day 1–8%; RSDinter-day 5–14%), accurate (intra-day: 95–107%; inter-day: 90–115%), and robust quantification of both pesticides from porcine urine and plasma after deproteinization by precipitation and extensive dilution (1:11,250 for plasma and 1:40,000 for urine). Accordingly, lower limits of quantification (0.24–0.49?g/ml plasma and 0.78–1.56?g/ml urine) and lower limits of detection (0.12–0.24?g/ml plasma and 0.39–0.78?g/ml urine) were equivalent to quite low absolute on-column amounts (1.1–2.1pg for plasma and 2.0–3.9pg for urine). The calibration range (0.24–250?g/ml plasma and 0.78–200?g/ml urine) was subdivided into two linear ranges (r2?0.998) each covering nearly two orders of magnitude. The lack of any interfering peak in 6 individual blank specimens from plasma and urine demonstrated the high selectivity of the method. Furthermore, extensive sample dilution causing lowest concentration of potentially interfering matrix ingredients prompted us to develop and validate an additional flow-injection method (FI-ESI-MS/MS). Validation characteristics were as good as for the chromatographic method but sample throughput was enhanced by a factor of 6. Effects on ionization provoked by plasma and urine matrix from 6 individuals as well as in the presence of therapeutics (antidotes) administered in an animal study were investigated systematically underling in the reliability of the presented methods. Both methods were applied to porcine samples derived from an in vivo animal study.

http://dx.doi.org/10.1016%2Fj.jchromb.2010.01.003

46. Joshi M.D., Anderson J.L. Recent advances of ionic liquids in separation science and mass spectrometry // RSC Adv. 2012. Vol. 2, № 13. P. 5470–5484.

Ionic liquids (ILs) have drawn considerable interest for their use in various analytical techniques including chromatography, extractions, and mass spectrometry. This is largely due to the flexibility in tuning the physicochemical properties of ILs. There has been a significant increase in the number of publications over the last decade in which ILs have been employed as a chromatographic stationary phase, extraction solvent, or sorbent material in various preconcentration techniques. This review article highlights the recent advancements in the use of ILs in separation science including gas chromatography, high-performance liquid chromatography, capillary electrophoresis, extraction and microextraction techniques as well as mass spectrometry.

http://dx.doi.org/10.1039%2Fc2ra20142a

47. U5177X
Kruve A., Herodes K., Leito I. Optimization of electrospray interface and quadrupole ion trap mass spectrometer parameters in pesticide liquid chromatography/electrospray ionization mass spectrometry analysis // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 7. P. 919–926.

Optimization of both the ionization process and ion transportation in the mass spectrometer is of crucial importance in order to achieve high sensitivity and low detection limits and acceptable accuracy in liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS) analysis. In this paper four optimization procedures of electrospray interface and quadrupole ion-trap mass spectrometer parameters (ESI-MS) (nebulizer gas and drying gas flow rate, end plate voltage, capillary voltage, skimmer voltage, octopoles direct current and radio frequency, trap drive and lens voltages) were studied on three pesticides – thiabendazole, aldicarb and imazalil. The results demonstrate that the methodology of optimization strongly influences the effectiveness of finding true optima of the operating parameters. Both eluent flow rate and composition during optimization have to mimic the situation during real analysis as closely as possible in order to achieve parameters giving the highest sensitivity. Therefore, post-column addition of analyte to the mobile phase identical in composition to the one in which analyte elutes during real analysis combined with software-based optimization was found to be the most effective and fastest method for achieving intensity maxima. The parameters most strongly affecting ion formation and transportation, hence sensitivity, were capillary voltage, direct current of the first octopole, trap drive and the second lens for all pesticides under study. In addition to sensitivity and detection limit matrix effect was considered in the optimization process. It was found that the matrix effect can be reduced but not eliminated by adjusting the ESI and MS parameters. The optimal parameters from the point of view of the matrix effect can only be found with factorial design. Parameters giving higher sensitivity tended to be more affected by matrix effect causing higher ionization suppression by co-eluting compounds.

http://dx.doi.org/10.1002%2Frcm.4470

48. U5177X
Kruve A., Herodes K., Leito I. Optimization of electrospray interface and quadrupole ion trap mass spectrometer parameters in pesticide liquid chromatography/electrospray ionization mass spectrometry analysis // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 7. P. 919–926.

Optimization of both the ionization process and ion transportation in the mass spectrometer is of crucial importance in order to achieve high sensitivity and low detection limits and acceptable accuracy in liquid chromatography/electrospray ionization mass spectrometry (LC/ESI-MS) analysis. In this paper four optimization procedures of electrospray interface and quadrupole ion-trap mass spectrometer parameters (ESI-MS) (nebulizer gas and drying gas flow rate, end plate voltage, capillary voltage, skimmer voltage, octopoles direct current and radio frequency, trap drive and lens voltages) were studied on three pesticides – thiabendazole, aldicarb and imazalil. The results demonstrate that the methodology of optimization strongly influences the effectiveness of finding true optima of the operating parameters. Both eluent flow rate and composition during optimization have to mimic the situation during real analysis as closely as possible in order to achieve parameters giving the highest sensitivity. Therefore, post-column addition of analyte to the mobile phase identical in composition to the one in which analyte elutes during real analysis combined with software-based optimization was found to be the most effective and fastest method for achieving intensity maxima. The parameters most strongly affecting ion formation and transportation, hence sensitivity, were capillary voltage, direct current of the first octopole, trap drive and the second lens for all pesticides under study. In addition to sensitivity and detection limit matrix effect was considered in the optimization process. It was found that the matrix effect can be reduced but not eliminated by adjusting the ESI and MS parameters. The optimal parameters from the point of view of the matrix effect can only be found with factorial design. Parameters giving higher sensitivity tended to be more affected by matrix effect causing higher ionization suppression by co-eluting compounds.

http://dx.doi.org/10.1002%2Frcm.4470

49. Kuehnbaum N.L., Britz-McKibbin P. New Advances in Separation Science for Metabolomics: Resolving Chemical Diversity in a Post-Genomic Era // Chem. Rev. 2013. Vol. 113, № 4. P. 2437–2468.

Recent developments in LC column technology over the past decade has greatly improved separation efficiency while expanding selectivity, which is now increasingly dominated by columns packed with fused-core and sub-2 ?m porous particles for ultrafast separations. The ratio of the hold-up time to column efficiency (i.e., Poppe plot) can be used to assess the resolving power of a separation system, which is favored with columns that possess high porosity and low plate heights while operating under high linear velocities.(175) The introduction of monolithic columns based on a continuous porous silica rod allows for fast separations because of its high porosity with plate heights comparable to conventional 5 ?m porous particles that is achieved at much lower back pressures. However, separation efficiency in monolithic columns is compromised by Eddy diffusion because of their radial heterogeneity in wide bore columns, which can be improved when using long and narrow capillary formats at low linear velocities.

http://dx.doi.org/10.1021%2Fcr300484s

50. Laemmerhofer M. Trends in Separation Science // J. Sep. Sci. 2013. Vol. 36, № 17. Editorial.

The current special issue called “Trends” should reflect and attribute these developments, even if not all recent advancements are covered adequately, incidentally.

http://dx.doi.org/10.1002%2Fjssc.201370164

51. Lenca N., Poole C.F. Liquid Chromatography with Room Temperature Ionic Liquids // JPC-J. Planar Chromatogr.-Mod. TLC. 2017. Vol. 30, № 2. P. 97–105.

Room temperature ionic liquids are a new class of solvents of potential interest for liquid chromatography. Ionic liquids possess a combination of physical and solvation properties that are complementary to conventional organic solvents. Applications in liquid chromatography are currently limited by their unfavorable viscosity and low-wavelength absorption in the ultraviolet (UV) region. In addition, for planar chromatography, the absence of a vapor pressure does not allow evaporation of ionic liquid solvents after development. The room temperature ionic liquids are good solvents for nonionic compounds with a different blend of intermolecular interactions compared with conventional organic solvents as indicated by solvatochromic measurements and the system constants of the solvation parameter model. Current applications in column and planar chromatography are reviewed to demonstrate the potential of room temperature ionic liquids as mobile phases or mobile phase additives in separation science. A real breakthrough in their use, however, requires the identification of new room temperature ionic liquids with viscosity closer to those of conventional organic solvents as well as addressing other minor issues described in the text.

http://dx.doi.org/10.1556%2F1006.2017.30.2.2

52. U45302
Lin S. et al. LC/MS-based non-targeted metabolomics for the investigation of general toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin in C57BL/6J and DBA/2J mice // International Journal of Mass Spectrometry. 2011. Vol. 301, № 1. P. 29–36.

Although numerous studies have been performed for the toxicological mechanisms of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), the metabolic changes of TCDD toxicity is less well understood. In this study, liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/QTOFMS) was used for non-targeted metabolomics for understanding the different metabolic patterns associated with TCDD exposure in aryl hydrocarbon receptor (AhR) sensitive C57BL/6J (C6) and less sensitive DBA/2J (D2) mouse strains. The serum samples were analyzed and treated with metabolomic analysis in conjunction with multivariate data analysis. Metabolite identification was performed with interpreting high resolution MS data and MS/MS fragmentation, searching against databases and comparing with authentic compounds. Twelve differentiating metabolites (defined as a ?1.5-fold change with a P?0.001) were highlighted in C6 mice versus control group, revealing lipid accumulation, fatty acid beta-oxidation, inflammation and alteration of amino acids as well as phase II drug-like metabolism. In contrast, only 2 differentiating metabolites were detected in D2 mouse model.

http://dx.doi.org/10.1016%2Fj.ijms.2010.06.012

53. Livengood J. Why was M. S. Tswett’s chromatographic adsorption analysis rejected? // Stud. Hist. Philos. Sci. 2009. Vol. 40, № 1. P. 57–69.

The present paper claims that M. S. Tswett's chromatographic adsorption analysis, which today is a ubiquitous and instrumentally sophisticated chemical technique, was either ignored or outright rejected by chemists and botanists in the first three decades of the twentieth century because it did not make sense in terms of accepted chemical theory or practice. Evidence for this claim is culled from consideration of the botanical and chemical context of Tswett's technique as well as an analysis of the protracted debate over Tswett's chromatographic analysis of chlorophyll between him and Leon Marchlewski, a noted chlorophyll chemist of the period. in this way, the paper expands and amends what it calls the 'textbook story' of the early history of chromatography, examples of which may be found in historical notes in many textbooks of chemical instrumental analysis and numerous short articles in chemistry journals. The paper also provides an accessible introduction to the early history of chromatography for historians of science likely to know little or nothing about it.

http://dx.doi.org/10.1016%2Fj.shpsa.2008.12.003

54. Lucci P., Nunez O. On-line solid-phase extraction for liquid chromatography-mass spectrometry analysis of pesticides // J. Sep. Sci. 2014. Vol. 37, № 20. P. 2929–2939.

Public concern about pesticides in food and water has increased dramatically in the last two decades. In order to guarantee consumers' health and safety, analytical methods that could provide fast and reliable answers without compromising accuracy and precision are required. Sample treatment is probably the most tedious and time-consuming step in many analytical procedures and, despite the significant advances in chromatographic separations and mass spectrometry techniques, sample treatment is still one of the most important parts of the analytical process for achieving good analytical results. Therefore, over the last years, considerable efforts have been made to simplify the stage and to develop fast, accurate, and robust methods that allow the determination of a wide range of pesticides without compromising the integrity of the extraction process. This review article intends to give a short overview of recently developed on-line solid-phase extraction, preconcentration, and clean-up procedures for the determination of pesticides in complex matrices by liquid chromatography-mass spectrometry techniques.

http://dx.doi.org/10.1002%2Fjssc.201400531

55. U54212
Lyakhovetsky Y.I. et al. Homolytic Reactive Mass Spectrometry of Fullerenes: Peculiarities of the Reactions of C60 with Aromatic Compounds in the Ionization Chambers of Mass Spectrometers and in Solution // J. Am. Soc. Mass Spectrom. 2013. Vol. 24, № 4. P. 579–588.

C60 reacted with PhH, PhCl, BnH, BnNH2, and o-C2H2B10H10 in the electron impact (EI) ion source of a mass spectrometer at 300 °C forming phenyl, benzyl, and o-carboranyl adducts, respectively, stabilized by hydrogen addition and loss. Besides, the additions to C60 of methyl and phenyl radicals for toluene, and a phenyl radical for benzylamine were observed. A homolytic reaction mechanism was suggested involving the reaction of the radicals formed from the aromatics under EI with C60 at the ionization chamber walls. While the ion/molecule reaction of C60 with benzene performed by Sun et al. under chemical ionization conditions at 200 °C afforded the complex C60•PhH+•, quite a different isomer, HC60Ph+•, was detected in the present study as a sequence of the different reaction mechanisms. C60 also reacted with benzyl bromide in the laser desorption/ionization (LDI) source of a mass spectrometer to give C60CPh+. Phenyl and benzyl derivatives of C60 were found, respectively, when the reactions of the fullerene with PhCl, BnH, and BnBr were performed in solution under ultra violet irradiation. For the reaction with toluene, the strong chemically induced dynamic electron polarization of the intermediate benzylfullerenyl radical with the reverse phase effect was found. The coincidence of the results of the mass spectrometry and solution reactions of C60 with aromatics, even though incomplete, additionally supports the hypothesis, formulated earlier, that the former results can predict the latter ones to a significant extent and shows that this conclusion is valid for both EI and LDI initiated reactions in mass spectrometers.Open image in new window

http://dx.doi.org/10.1007%2Fs13361-012-0550-4

56. U54212
Lyakhovetsky Y.I. et al. Homolytic Reactive Mass Spectrometry of Fullerenes: Peculiarities of the Reactions of C60 with Aromatic Compounds in the Ionization Chambers of Mass Spectrometers and in Solution // J. Am. Soc. Mass Spectrom. 2013. Vol. 24, № 4. P. 579–588.

C60 reacted with PhH, PhCl, BnH, BnNH2, and o-C2H2B10H10 in the electron impact (EI) ion source of a mass spectrometer at 300 °C forming phenyl, benzyl, and o-carboranyl adducts, respectively, stabilized by hydrogen addition and loss. Besides, the additions to C60 of methyl and phenyl radicals for toluene, and a phenyl radical for benzylamine were observed. A homolytic reaction mechanism was suggested involving the reaction of the radicals formed from the aromatics under EI with C60 at the ionization chamber walls. While the ion/molecule reaction of C60 with benzene performed by Sun et al. under chemical ionization conditions at 200 °C afforded the complex C60•PhH+•, quite a different isomer, HC60Ph+•, was detected in the present study as a sequence of the different reaction mechanisms. C60 also reacted with benzyl bromide in the laser desorption/ionization (LDI) source of a mass spectrometer to give C60CPh+. Phenyl and benzyl derivatives of C60 were found, respectively, when the reactions of the fullerene with PhCl, BnH, and BnBr were performed in solution under ultra violet irradiation. For the reaction with toluene, the strong chemically induced dynamic electron polarization of the intermediate benzylfullerenyl radical with the reverse phase effect was found. The coincidence of the results of the mass spectrometry and solution reactions of C60 with aromatics, even though incomplete, additionally supports the hypothesis, formulated earlier, that the former results can predict the latter ones to a significant extent and shows that this conclusion is valid for both EI and LDI initiated reactions in mass spectrometers.Open image in new window

http://dx.doi.org/10.1007%2Fs13361-012-0550-4

57. Maatta J.A. et al. Inactivation of estrogen receptor alpha in bone-forming cells induces bone loss in female mice // Faseb J. 2013. Vol. 27, № 2. P. 478–488.

The role of the estrogen receptor alpha (ER alpha) in bone-forming cells is incompletely understood at present. To examine the in vivo effects of ER alpha in these cells, we generated a mouse strain in which the ER alpha gene is inactivated in osteoblasts via osteocalcin promoter-regulated cyclic recombinase (Cre) activity (ER alpha(Delta OB/Delta OB)). This enabled micro-computed tomography- and histomorphometry-based analysis of ER alpha-mediated effects in bone-forming cells in mice, in which the systemic ER alpha-mediated effects are intact. In female ER alpha(Delta OB/Delta OB) mice, trabecular and cortical bone volumes were significantly reduced (31.5 and 11.4%, respectively) at 3.5 mo of age compared with control ER alpha(fl/fl) animals, and their response to ovariectomy was small compared with that of controls. In contrast with females, no differences could be detected in the bone phenotype of young males, whereas in 6-mo-old ER alpha(Delta OB/Delta OB) males, trabecular bone volume (Tb.BV) was decreased (27.5%). The ER alpha inactivation-related effects were compared with those of controls having a similar genetic background. Parental osteocalcin-Cre mice did not show Cre-related changes. Our results suggest that in female mice, Tb.BV and cortical bone volume are critically dependent on the ER alpha regulation of osteoblasts, whereas in male mice, osteoblastic ER alpha is not required for the regulation of bone formation during rapid skeletal growth, but it is involved in the maintenance of Tb.BV.-Maatta, J. A., Buki, K. G., Gu, G., Alanne, M. H., Vaaraniemi, J., Liljenback, H., Poutanen, M., Harkonen, P., Vaananen, K. Inactivation of estrogen receptor alpha in bone-forming cells induces bone loss in female mice. FASEB J. 27, 478-488 (2013). www.fasebj.org

http://dx.doi.org//10.1096/fj.12-213587

58. Mansour F.R., Zhou L., Danielson N.D. Applications of Poly(Ethylene)Glycol (PEG) in Separation Science // Chromatographia. 2015. Vol. 78, № 23–24. P. 1427–1442.

The wide range of applications of poly(ethylene)glycol (PEG) in primarily chromatography and other closely related analytical methods has been reviewed. PEG has been used as mobile phase modifier in capillary electrophoresis (CE) as well as ion exchange, size exclusion, and hydrophobic interaction liquid chromatography (LC) methods. Generally in the presence of PEG, LC retention of macromolecules is altered and stability of their structure is maintained. PEG was effective in CE as a permanent coating for fused silica capillaries to shield free silanol groups that can cause protein adsorption to the wall resulting in band broadening and low recovery of the separated proteins. In gas chromatography, PEG-based stationary phases were applied for separation of polar analytes. PEG could also serve as an extraction medium in solid phase microextraction and aqueous two phase systems. Selected analytical applications, primarily LC and CE, involving PEG to facilitate the determination of either small molecules or macromolecules such as proteins in their native form are discussed and representative figures provided.

http://dx.doi.org/10.1007%2Fs10337-015-2983-y

59. U5177X
McCullagh J.S.O. Mixed-mode chromatography/isotope ratio mass spectrometry // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 5. P. 483–494.

Liquid chromatography coupled to molecular mass spectrometry (LC/MS) has been a standard technique since the early 1970s but liquid chromatography coupled to high-precision isotope ratio mass spectrometry (LC/IRMS) has only been available commercially since 2004. This development has, for the first time, enabled natural abundance and low enrichment ?13C measurements to be applied to individual analytes in aqueous mixtures creating new opportunities for IRMS applications, particularly for the isotopic study of biological molecules. A growing number of applications have been published in a range of areas including amino acid metabolism, carbohydrates studies, quantification of cellular and plasma metabolites, dietary tracer and nucleic acid studies. There is strong potential to extend these to new compounds and complex matrices but several challenges face the development of LC/IRMS methods. To achieve accurate isotopic measurements, HPLC separations must provide baseline-resolution between analyte peaks; however, the design of current liquid interfaces places severe restrictions on compatible flow rates and in particular mobile phase compositions. These create a significant challenge on which reports associated with LC/IRMS have not previously focused. Accordingly, this paper will address aspects of chromatography in the context of LC/IRMS, in particular focusing on mixed-mode separations and their benefits in light of these restrictions. It aims to provide an overview of mixed-mode stationary phases and of ways to improve high aqueous separations through manipulation of parameters such as column length, temperature and mobile phase pH. The results of several practical experiments are given using proteogenic amino acids and nucleosides both of which are of noted importance in the LC/IRMS literature. This communication aims to demonstrate that mixed-mode stationary phases provide a flexible approach given the constraints of LC/IRMS interface design and acts as a practical guide for the development of new chromatographic methods compatible with LC/IRMS applications.

http://dx.doi.org/10.1002%2Frcm.4322

60. U5177X
McCullagh J.S.O. Mixed-mode chromatography/isotope ratio mass spectrometry // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 5. P. 483–494.

Liquid chromatography coupled to molecular mass spectrometry (LC/MS) has been a standard technique since the early 1970s but liquid chromatography coupled to high-precision isotope ratio mass spectrometry (LC/IRMS) has only been available commercially since 2004. This development has, for the first time, enabled natural abundance and low enrichment ?13C measurements to be applied to individual analytes in aqueous mixtures creating new opportunities for IRMS applications, particularly for the isotopic study of biological molecules. A growing number of applications have been published in a range of areas including amino acid metabolism, carbohydrates studies, quantification of cellular and plasma metabolites, dietary tracer and nucleic acid studies. There is strong potential to extend these to new compounds and complex matrices but several challenges face the development of LC/IRMS methods. To achieve accurate isotopic measurements, HPLC separations must provide baseline-resolution between analyte peaks; however, the design of current liquid interfaces places severe restrictions on compatible flow rates and in particular mobile phase compositions. These create a significant challenge on which reports associated with LC/IRMS have not previously focused. Accordingly, this paper will address aspects of chromatography in the context of LC/IRMS, in particular focusing on mixed-mode separations and their benefits in light of these restrictions. It aims to provide an overview of mixed-mode stationary phases and of ways to improve high aqueous separations through manipulation of parameters such as column length, temperature and mobile phase pH. The results of several practical experiments are given using proteogenic amino acids and nucleosides both of which are of noted importance in the LC/IRMS literature. This communication aims to demonstrate that mixed-mode stationary phases provide a flexible approach given the constraints of LC/IRMS interface design and acts as a practical guide for the development of new chromatographic methods compatible with LC/IRMS applications.

http://dx.doi.org/10.1002%2Frcm.4322

61. Meinert C., Meierhenrich U.J. A New Dimension in Separation Science: Comprehensive Two-Dimensional Gas Chromatography // Angew. Chem.-Int. Edit. 2012. Vol. 51, № 42. P. 10460–10470.

The introduction and development of comprehensive two-dimensional gas chromatography offers greatly enhanced resolution and identification of organic analytes in complex mixtures compared to any one-dimensional separation technique. Initially promoted by the need to resolve highly complex petroleum samples, the techniques enormous separation power and enhanced ability to gather information has rapidly attracted the attention of analysts from all scientific fields. In this Minireview, we highlight the fundamental theory, recent advances, and future trends in the instrumentation and application of comprehensive two-dimensional column separation.

http://dx.doi.org/10.1002%2Fanie.201200842

62. U01982
Mellors J.S. et al. Hybrid Capillary/Microfluidic System for Comprehensive Online Liquid Chromatography-Capillary Electrophoresis-Electrospray Ionization-Mass Spectrometry // Anal. Chem. 2013. Vol. 85, № 8. P. 4100–4106.

A hybrid multidimensional separation system was made by coupling capillary liquid chromatography (LC) to a microfluidic device. The microfluidic device integrated flow splitting, capillary electrophoresis (CE), electroosmotic pumping, and electrospray ionization (ESI) emitter functional elements. The system was used with a time-of-flight mass spectrometer for comprehensive online LC-CE-MS of proteolytic digests. Analysis of a complex mixture of peptides yielded a peak capacity of approximately 1400 in 50 min. Three replicate runs demonstrated mean reproducibility for LC retention and CE migration times of 0.32% and 0.75% relative standard deviation (RSD), respectively. The same LC-CE-MS method was also used to characterize the N-linked glycosylation of a monoclonal antibody. Glycopeptides from two different N-linked glycosylation sites were separated from all other tryptic peptides and identified using MS data. The relative amounts of each glycoform and total site occupancy were quantified using LC-CE-MS data.

http://dx.doi.org/10.1021%2Fac400205a

63. U01982
Mellors J.S. et al. Hybrid Capillary/Microfluidic System for Comprehensive Online Liquid Chromatography-Capillary Electrophoresis-Electrospray Ionization-Mass Spectrometry // Anal. Chem. 2013. Vol. 85, № 8. P. 4100–4106.

A hybrid multidimensional separation system was made by coupling capillary liquid chromatography (LC) to a microfluidic device. The microfluidic device integrated flow splitting, capillary electrophoresis (CE), electroosmotic pumping, and electrospray ionization (ESI) emitter functional elements. The system was used with a time-of-flight mass spectrometer for comprehensive online LC-CE-MS of proteolytic digests. Analysis of a complex mixture of peptides yielded a peak capacity of approximately 1400 in 50 min. Three replicate runs demonstrated mean reproducibility for LC retention and CE migration times of 0.32% and 0.75% relative standard deviation (RSD), respectively. The same LC-CE-MS method was also used to characterize the N-linked glycosylation of a monoclonal antibody. Glycopeptides from two different N-linked glycosylation sites were separated from all other tryptic peptides and identified using MS data. The relative amounts of each glycoform and total site occupancy were quantified using LC-CE-MS data.

http://dx.doi.org/10.1021%2Fac400205a

64. U15769
Miller E.I. et al. A novel validated procedure for the determination of nicotine, eight nicotine metabolites and two minor tobacco alkaloids in human plasma or urine by solid-phase extraction coupled with liquid chromatography–electrospray ionization–tandem mass spectrometry // Journal of Chromatography B. 2010. Vol. 878, № 9. P. 725–737.

A novel validated liquid chromatography–tandem mass spectrometry (LC–MS/MS) procedure was developed and fully validated for the simultaneous determination of nicotine-N-?-d-glucuronide, cotinine-N-oxide, trans-3-hydroxycotinine, norcotinine, trans-nicotine-1?-oxide, cotinine, nornicotine, nicotine, anatabine, anabasine and cotinine-N-?-d-glucuronide in human plasma or urine. Target analytes and corresponding deuterated internal standards were extracted by solid-phase extraction and analyzed by LC–MS/MS with electrospray ionization (ESI) using multiple reaction monitoring (MRM) data acquisition. Calibration curves were linear over the selected concentration ranges for each analyte, with calculated coefficients of determination (R2) of greater than 0.99. The total extraction recovery (%) was concentration dependent and ranged between 52–88% in plasma and 51–118% in urine. The limits of quantification for all analytes in plasma and urine were 1.0ng/mL and 2.5ng/mL, respectively, with the exception of cotinine-N-?-d-glucuronide, which was 50ng/mL. Intra-day and inter-day imprecision were ?14% and ?17%, respectively. Matrix effect (%) was sufficiently minimized to ?19% for both matrices using the described sample preparation and extraction methods. The target analytes were stable in both matrices for at least 3 freeze–thaw cycles, 24h at room temperature, 24h in the refrigerator (4°C) and 1 week in the freezer (?20°C). Reconstituted plasma and urine extracts were stable for at least 72h storage in the liquid chromatography autosampler at 4°C. The plasma procedure has been successfully applied in the quantitative determination of selected analytes in samples collected from nicotine-abstinent human participants as part of a pharmacokinetic study investigating biomarkers of nicotine use in plasma following controlled low dose (7mg) transdermal nicotine delivery. Nicotine, cotinine, trans-3-hydroxycotinine and trans-nicotine-1?-oxide were detected in the particular sample presented herein. The urine procedure has been used to facilitate the monitoring of unauthorized tobacco use by clinical study participants at the time of physical examination (before enrollment) and on the pharmacokinetic study day.

http://dx.doi.org/10.1016%2Fj.jchromb.2009.12.018

65. U5177X
Oh J.H. et al. MSQ: a tool for quantification of proteomics data generated by a liquid chromatography/matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry based targeted quantitative proteomics platform // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 4. P. 403–408.

Mass spectrometry (MS)-based quantitative proteomics has become a critical component of biological and clinical research for identification of biomarkers that can be used for early detection of diseases. In particular, MS-based targeted quantitative proteomics has been recently developed for the detection and validation of biomarker candidates in complex biological samples. In such approaches, synthetic reference peptides that are the stable isotope labeled version of proteotypic peptides of proteins to be quantitated are used as internal standards enabling specific identification and absolute quantification of targeted peptides. The quantification of targeted peptides is achieved using the intensity ratio of a native peptide to the corresponding reference peptide whose spike-in amount is known. However, a manual calculation of the ratios can be time-consuming and labor-intensive, especially when the number of peptides to be tested is large. To establish a liquid chromatography/matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (LC/MALDI TOF/TOF)-based targeted quantitative proteomics pipeline, we have developed a software named Mass Spectrometry based Quantification (MSQ). This software can be used to automate the quantification and identification of targeted peptides/proteins by the MALDI TOF/TOF platform. MSQ was applied to the detection of a selected group of targeted peptides in pooled human cerebrospinal spinal fluid (CSF) from patients with Alzheimer's disease (AD) in comparison with age-matched control (OC). The results for the automated quantification and identification of targeted peptides/proteins in CSF were in good agreement with results calculated manually.

http://dx.doi.org/10.1002%2Frcm.4407

66. U5177X
Oh J.H. et al. MSQ: a tool for quantification of proteomics data generated by a liquid chromatography/matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry based targeted quantitative proteomics platform // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 4. P. 403–408.

Mass spectrometry (MS)-based quantitative proteomics has become a critical component of biological and clinical research for identification of biomarkers that can be used for early detection of diseases. In particular, MS-based targeted quantitative proteomics has been recently developed for the detection and validation of biomarker candidates in complex biological samples. In such approaches, synthetic reference peptides that are the stable isotope labeled version of proteotypic peptides of proteins to be quantitated are used as internal standards enabling specific identification and absolute quantification of targeted peptides. The quantification of targeted peptides is achieved using the intensity ratio of a native peptide to the corresponding reference peptide whose spike-in amount is known. However, a manual calculation of the ratios can be time-consuming and labor-intensive, especially when the number of peptides to be tested is large. To establish a liquid chromatography/matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (LC/MALDI TOF/TOF)-based targeted quantitative proteomics pipeline, we have developed a software named Mass Spectrometry based Quantification (MSQ). This software can be used to automate the quantification and identification of targeted peptides/proteins by the MALDI TOF/TOF platform. MSQ was applied to the detection of a selected group of targeted peptides in pooled human cerebrospinal spinal fluid (CSF) from patients with Alzheimer's disease (AD) in comparison with age-matched control (OC). The results for the automated quantification and identification of targeted peptides/proteins in CSF were in good agreement with results calculated manually.

http://dx.doi.org/10.1002%2Frcm.4407

67. U54212
Petre B.-A. et al. When is Mass Spectrometry Combined with Affinity Approaches Essential? A Case Study of Tyrosine Nitration in Proteins // J. Am. Soc. Mass Spectrom. 2012. Vol. 23, № 11. P. 1831–1840.

Tyrosine nitration in proteins occurs under physiologic conditions and is increased at disease conditions associated with oxidative stress, such as inflammation and Alzheimer’s disease. Identification and quantification of tyrosine-nitrations are crucial for understanding nitration mechanism(s) and their functional consequences. Mass spectrometry (MS) is best suited to identify nitration sites, but is hampered by low stabilities and modification levels and possible structural changes induced by nitration. In this insight, we discuss methods for identifying and quantifying nitration sites by proteolytic affinity extraction using nitrotyrosine (NT)-specific antibodies, in combination with electrospray-MS. The efficiency of this approach is illustrated by identification of specific nitration sites in two proteins in eosinophil granules from several biological samples, eosinophil-cationic protein (ECP) and eosinophil-derived neurotoxin (EDN). Affinity extraction combined with Edman sequencing enabled the quantification of nitration levels, which were found to be 8 % and 15 % for ECP and EDN, respectively. Structure modeling utilizing available crystal structures and affinity studies using synthetic NT-peptides suggest a tyrosine nitration sequence motif comprising positively charged residues in the vicinity of the NT- residue, located at specific surface- accessible sites of the protein structure. Affinities of Tyr-nitrated peptides from ECP and EDN to NT-antibodies, determined by online bioaffinity- MS, provided nanomolar KD values. In contrast, false-positive identifications of nitrations were obtained in proteins from cystic fibrosis patients upon using NT-specific antibodies, and were shown to be hydroxy-tyrosine modifications. These results demonstrate affinity- mass spectrometry approaches to be essential for unequivocal identification of biological tyrosine nitrations.

http://dx.doi.org/10.1007%2Fs13361-012-0461-4

68. U54212
Petre B.-A. et al. When is Mass Spectrometry Combined with Affinity Approaches Essential? A Case Study of Tyrosine Nitration in Proteins // J. Am. Soc. Mass Spectrom. 2012. Vol. 23, № 11. P. 1831–1840.

Tyrosine nitration in proteins occurs under physiologic conditions and is increased at disease conditions associated with oxidative stress, such as inflammation and Alzheimer’s disease. Identification and quantification of tyrosine-nitrations are crucial for understanding nitration mechanism(s) and their functional consequences. Mass spectrometry (MS) is best suited to identify nitration sites, but is hampered by low stabilities and modification levels and possible structural changes induced by nitration. In this insight, we discuss methods for identifying and quantifying nitration sites by proteolytic affinity extraction using nitrotyrosine (NT)-specific antibodies, in combination with electrospray-MS. The efficiency of this approach is illustrated by identification of specific nitration sites in two proteins in eosinophil granules from several biological samples, eosinophil-cationic protein (ECP) and eosinophil-derived neurotoxin (EDN). Affinity extraction combined with Edman sequencing enabled the quantification of nitration levels, which were found to be 8 % and 15 % for ECP and EDN, respectively. Structure modeling utilizing available crystal structures and affinity studies using synthetic NT-peptides suggest a tyrosine nitration sequence motif comprising positively charged residues in the vicinity of the NT- residue, located at specific surface- accessible sites of the protein structure. Affinities of Tyr-nitrated peptides from ECP and EDN to NT-antibodies, determined by online bioaffinity- MS, provided nanomolar KD values. In contrast, false-positive identifications of nitrations were obtained in proteins from cystic fibrosis patients upon using NT-specific antibodies, and were shown to be hydroxy-tyrosine modifications. These results demonstrate affinity- mass spectrometry approaches to be essential for unequivocal identification of biological tyrosine nitrations.

http://dx.doi.org/10.1007%2Fs13361-012-0461-4

69. Pino V. et al. Ionic Liquid-Based Surfactants in Separation Science // Separation Science and Technology. 2012. Vol. 47, № 2. P. 264–276.

A group of nearly forty-eight (48) of surfactants based on ionic liquids (ILs) has been described. The physicochemical and interfacial behavior for several of these IL-based surfactants has been reported since 2004. This review attempts to summarize the important applications that IL-based surfactants have had in analytical chemistry and separation science. Thus, they have been successfully used as extractant systems as substitutes to conventional organic solvents in extraction schemes, or by modifying the chemical structure of conventional extractant sorbents. The analytical performance of these novel IL-based surfactants has been shown to be better than conventional solvents and even better than conventional cationic surfactants. IL-based surfactants have also been used as mobile phase and stationary phase modifiers in high-performance liquid chromatography (HPLC), as modifiers of the electrokinetic chromatographic (EKC) medium, or as the micellar component in capillary electrophoresis (CE). Thus, IL-based surfactant methods constitute a promising and developing area within separation science.

http://dx.doi.org/10.1080%2F01496395.2011.620589

70. Posch T.N. et al. Electromigrative separation techniques in forensic science: Combining selectivity, sensitivity, and robustness // Analytical and Bioanalytical Chemistry. 2015. Vol. 407, № 1. P. 23–58.

In this review we introduce the advantages and limitations of electromigrative separation techniques in forensic toxicology. We thus present a summary of illustrative studies and our own experience in the field together with established methods from the German Federal Criminal Police Office rather than a complete survey. We focus on the analytical aspects of analytes' physicochemical characteristics (e.g. polarity, stereoisomers) and analytical challenges including matrix tolerance, separation from compounds present in large excess, sample volumes, and orthogonality. For these aspects we want to reveal the specific advantages over more traditional methods. Both detailed studies and profiling and screening studies are taken into account. Care was taken to nearly exclusively document well-validated methods outstanding for the analytical challenge discussed. Special attention was paid to aspects exclusive to electromigrative separation techniques, including the use of the mobility axis, the potential for on-site instrumentation, and the capillary format for immunoassays. The review concludes with an introductory guide to method development for different separation modes, presenting typical buffer systems as starting points for different analyte classes. The objective of this review is to provide an orientation for users in separation science considering using capillary electrophoresis in their laboratory in the future.

http://dx.doi.org/10.1007%2Fs00216-014-8271-0

71. U5177X
Remane D. et al. Systematic investigation of ion suppression and enhancement effects of fourteen stable-isotope-labeled internal standards by their native analogues using atmospheric-pressure chemical ionization and electrospray ionization and the relevance for multi-analyte liquid chromatographic/mass spectrometric procedures // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 7. P. 859–867.

In clinical and forensic toxicology, multi-analyte procedures are very useful to quantify drugs and poisons of different classes in one run. For liquid chromatographic/tandem mass spectrometric (LC/MS/MS) multi-analyte procedures, often only a limited number of stable-isotope-labeled internal standards (SIL-ISs) are available. If an SIL-IS is used for quantification of other analytes, it must be excluded that the co-eluting native analyte influences its ionization. Therefore, the effect of ion suppression and enhancement of fourteen SIL-ISs caused by their native analogues has been studied. It could be shown that the native analyte concentration influenced the extent of ion suppression and enhancement effects leading to more suppression with increasing analyte concentration especially when electrospray ionization (ESI) was used. Using atmospheric-pressure chemical ionization (APCI), methanolic solution showed mainly enhancement effects, whereas no ion suppression and enhancement effect, with one exception, occurred when plasma extracts were used under these conditions. Such differences were not observed using ESI. With ESI, eleven SIL-ISs showed relevant suppression effects, but only one analyte showed suppression effects when APCI was used. The presented study showed that ion suppression and enhancement tests using matrix-based samples of different sources are essential for the selection of ISs, particularly if used for several analytes to avoid incorrect quantification. In conclusion, only SIL-ISs should be selected for which no suppression and enhancement effects can be observed. If not enough ISs are free of ionization interferences, a different ionization technique should be considered.

http://dx.doi.org/10.1002%2Frcm.4459

72. U5177X
Remane D. et al. Systematic investigation of ion suppression and enhancement effects of fourteen stable-isotope-labeled internal standards by their native analogues using atmospheric-pressure chemical ionization and electrospray ionization and the relevance for multi-analyte liquid chromatographic/mass spectrometric procedures // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 7. P. 859–867.

In clinical and forensic toxicology, multi-analyte procedures are very useful to quantify drugs and poisons of different classes in one run. For liquid chromatographic/tandem mass spectrometric (LC/MS/MS) multi-analyte procedures, often only a limited number of stable-isotope-labeled internal standards (SIL-ISs) are available. If an SIL-IS is used for quantification of other analytes, it must be excluded that the co-eluting native analyte influences its ionization. Therefore, the effect of ion suppression and enhancement of fourteen SIL-ISs caused by their native analogues has been studied. It could be shown that the native analyte concentration influenced the extent of ion suppression and enhancement effects leading to more suppression with increasing analyte concentration especially when electrospray ionization (ESI) was used. Using atmospheric-pressure chemical ionization (APCI), methanolic solution showed mainly enhancement effects, whereas no ion suppression and enhancement effect, with one exception, occurred when plasma extracts were used under these conditions. Such differences were not observed using ESI. With ESI, eleven SIL-ISs showed relevant suppression effects, but only one analyte showed suppression effects when APCI was used. The presented study showed that ion suppression and enhancement tests using matrix-based samples of different sources are essential for the selection of ISs, particularly if used for several analytes to avoid incorrect quantification. In conclusion, only SIL-ISs should be selected for which no suppression and enhancement effects can be observed. If not enough ISs are free of ionization interferences, a different ionization technique should be considered.

http://dx.doi.org/10.1002%2Frcm.4459

73. U5177X
Rossi S.S., de la Torre X., Botre F. A fast gas chromatography/mass spectrometry method for the determination of stimulants and narcotics in urine // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 10. P. 1475–1480.

A fast method has been developed for the simultaneous determination of 52 stimulants and narcotics excreted unconjugated in urine by gas chromatography/mass spectrometry (GC/MS). The procedure involves the liquid/liquid extraction of the analytes from urine at strong alkaline pH and the injection of the extract into a GC/MS instrument with a fast GC column (10?m???0.18?mm i.d.); the short column allows the complete separation of the 52 analytes in a chromatographic run of 8?min. The method has been fully validated giving lower limits of detection (LLODs) satisfactory for its application to antidoping analysis as well as to forensic toxicology. The repeatability of the concentrations and the retention times are good both for intra- and for inter-day experiments (%CV of concentrations always lower than 15 and %CV of retention times lower than 0.6). In addition, the analytical bias is satisfactory (A% always >15%). The method proposed here would be particularly useful whenever there are time constraints and the analyses have to be completed in the shortest possible time.

http://dx.doi.org/10.1002%2Frcm.4542

74. U5177X
Rossi S.S., de la Torre X., Botre F. A fast gas chromatography/mass spectrometry method for the determination of stimulants and narcotics in urine // Rapid Commun. Mass Spectrom. 2010. Vol. 24, № 10. P. 1475–1480.

A fast method has been developed for the simultaneous determination of 52 stimulants and narcotics excreted unconjugated in urine by gas chromatography/mass spectrometry (GC/MS). The procedure involves the liquid/liquid extraction of the analytes from urine at strong alkaline pH and the injection of the extract into a GC/MS instrument with a fast GC column (10?m???0.18?mm i.d.); the short column allows the complete separation of the 52 analytes in a chromatographic run of 8?min. The method has been fully validated giving lower limits of detection (LLODs) satisfactory for its application to antidoping analysis as well as to forensic toxicology. The repeatability of the concentrations and the retention times are good both for intra- and for inter-day experiments (%CV of concentrations always lower than 15 and %CV of retention times lower than 0.6). In addition, the analytical bias is satisfactory (A% always >15%). The method proposed here would be particularly useful whenever there are time constraints and the analyses have to be completed in the shortest possible time.

http://dx.doi.org/10.1002%2Frcm.4542

75. 04504X
Rudakova L.V., Rudakov O.B. One hundred and ten years of Russian chromatography // Сорбционные и хроматографические процессы. 2014. Т. 14, № 1. С. 8–13.

Рассмотрены этапы развития хроматографии и существующих научных хроматографических школ в России.

https://elibrary.ru/item.asp?id=21481471

76. U01982
Russell B.C., Warwick P.E., Croudace I.W. Calixarene-based Extraction Chromatographic Separation of 135Cs and 137Cs in Environmental and Waste Samples Prior to Sector Field ICP-MS Analysis // Anal. Chem. 2014. Vol. 86, № 23. P. 11890–11896.

Advances in the sensitivities achievable by sector field inductively coupled plasma mass spectrometry (ICP-SFMS) offer the prospect of low-level measurement of shorter and longer lived radionuclides, thus expanding options for environmental and radioactively contaminated land assessment. In ICP-SFMS, the critical requirement for accurate detection is the effective chemical separation of isobaric and polyatomic interferences prior to sample introduction. As instrumental detection limit capability improves, accurate radionuclide determination requires highly effective separation materials that combine high analyte selectivity with subsequent quantitative analyte recovery compatible with ICP-SFMS detection. Two radioactive isotopes measurable by ICP-SFMS are the high yield fission products 135Cs and 137Cs that have entered the environment as a result of anthropogenic nuclear activities. ICP-SFMS enables reliable measurement of 135Cs/137Cs ratios, which can be used as a forensic tool in determining the source of nuclear contamination. The critical requirement for accurate detection is the effective removal of isobaric interferences from 135Ba and 137Ba prior to measurement. A number of exchange materials can effectively extract Cs; however, non-quantitative elution of Cs makes subsequent ICP-SFMS quantification challenging. A novel extraction chromatographic resin has been developed by dissolving calix[4]arene-bis(tert-octylbenzo-crown-6) (BOBCalixC6) in octan-1-ol and loading onto an Amberchrom CG-71 prefilter resin material. Preparation of the material takes less than 1 h and, at an optimal concentration of 3 M HNO3, shows high selectivity toward Cs, which is effectively eluted in 0.05 M HNO3. The procedure developed shows high Cs selectivity and Ba decontamination from digests of complex matrixes including a saltmarsh sediment contaminated by aqueous discharges from a nuclear fuel reprocessing facility. Repeated tests show the resin can be reused up to four times. For low-level ICP-SFMS quantification, more complex sample matrixes benefit from a cation resin cleanup stage prior to using BOBCalixC6 that serves to enhance Ba decontamination and Cs recovery.

http://dx.doi.org/10.1021%2Fac5036988

77. U01982
Russell B.C., Warwick P.E., Croudace I.W. Calixarene-based Extraction Chromatographic Separation of 135Cs and 137Cs in Environmental and Waste Samples Prior to Sector Field ICP-MS Analysis // Anal. Chem. 2014. Vol. 86, № 23. P. 11890–11896.

Advances in the sensitivities achievable by sector field inductively coupled plasma mass spectrometry (ICP-SFMS) offer the prospect of low-level measurement of shorter and longer lived radionuclides, thus expanding options for environmental and radioactively contaminated land assessment. In ICP-SFMS, the critical requirement for accurate detection is the effective chemical separation of isobaric and polyatomic interferences prior to sample introduction. As instrumental detection limit capability improves, accurate radionuclide determination requires highly effective separation materials that combine high analyte selectivity with subsequent quantitative analyte recovery compatible with ICP-SFMS detection. Two radioactive isotopes measurable by ICP-SFMS are the high yield fission products 135Cs and 137Cs that have entered the environment as a result of anthropogenic nuclear activities. ICP-SFMS enables reliable measurement of 135Cs/137Cs ratios, which can be used as a forensic tool in determining the source of nuclear contamination. The critical requirement for accurate detection is the effective removal of isobaric interferences from 135Ba and 137Ba prior to measurement. A number of exchange materials can effectively extract Cs; however, non-quantitative elution of Cs makes subsequent ICP-SFMS quantification challenging. A novel extraction chromatographic resin has been developed by dissolving calix[4]arene-bis(tert-octylbenzo-crown-6) (BOBCalixC6) in octan-1-ol and loading onto an Amberchrom CG-71 prefilter resin material. Preparation of the material takes less than 1 h and, at an optimal concentration of 3 M HNO3, shows high selectivity toward Cs, which is effectively eluted in 0.05 M HNO3. The procedure developed shows high Cs selectivity and Ba decontamination from digests of complex matrixes including a saltmarsh sediment contaminated by aqueous discharges from a nuclear fuel reprocessing facility. Repeated tests show the resin can be reused up to four times. For low-level ICP-SFMS quantification, more complex sample matrixes benefit from a cation resin cleanup stage prior to using BOBCalixC6 that serves to enhance Ba decontamination and Cs recovery.

http://dx.doi.org/10.1021%2Fac5036988

78. Scriba G.K.E. Chiral recognition in separation science – an update // Journal of Chromatography A. 2016. Vol. 1467. P. 56–78.

Stereospecific recognition of chiral molecules is an important issue in various aspects of life sciences and chemistry including analytical separation sciences. The basis of analytical enantioseparations is the formation of transient diastereomeric complexes driven by hydrogen bonds or ionic, ion-dipole, dipole dipole, van der Waals as well as pi-pi interactions. Recently, halogen bonding was also described to contribute to selector-selectand complexation. Besides structure-separation relationships, spectroscopic techniques, especially NMR spectroscopy, as well as X-ray crystallography have contributed to the understanding of the structure of the diastereomeric complexes. Molecular modeling has provided the tool for the visualization of the structures. The present review highlights recent contributions to the understanding of the binding mechanism between chiral selectors and selectands in analytical enantioseparations dating between 2012 and early 2016 including polysaccharide derivatives, cyclodextrins, cyclofructans, macrocyclic glycopeptides, proteins, brush-type selectors, ion-exchangers, polymers, crown ethers, ligand-exchangers, molecular micelles, ionic liquids, metal-organic frameworks and nucleotide-derived selectors. A systematic compilation of all published literature on the various chiral selectors has not been attempted. (C) 2016 Elsevier B.V. All rights reserved.

http://dx.doi.org/10.1016%2Fj.chroma.2016.05.061

79. Silva M. Micellar electrokinetic chromatography: A review of methodological and instrumental innovations focusing on practical aspects // ELECTROPHORESIS. 2013. Vol. 34, № 1. P. 141–158.

This review article addresses recent methodological and instrumental innovations in MEKC with emphasis on practical aspects. Like its predecessors, this review is intended to provide an updated overview covering work on the most salient methodological contributions to enhancing sensitivity and resolution in MEKC-based determinations published over the past two years. The most widespread approaches to enhancing sensitivity, which include improving “classical” online sample concentration techniques, combinations of on- and off-line sample concentration protocols and recent developments are discussed, and so are modifications of existing MEKC systems with various micellar phases, the use of BGE additives (organic modifiers, chiral selectors, gold nanoparticles) and coated capillaries, and the implementation of 2D separations and chemometric methods to enhance resolution. Instrumental approaches such as MS and LIF are also discussed, and proposals for overcoming the problems typically encountered in directly coupling MEKC with MS, and the recent inception of quantum dots with a great potential for LIF detection in MEKC, are also dealt with. Finally, foreseeable developments on potential future directions are also expressed.

http://dx.doi.org/10.1002%2Felps.201200349

80. U15769
Szafarz M. et al. Simultaneous determination of nicotinic acid and its four metabolites in rat plasma using high performance liquid chromatography with tandem mass spectrometric detection (LC/MS/MS) // Journal of Chromatography B. 2010. Vol. 878, № 11. P. 895–902.

A sensitive and specific liquid chromatography electrospray ionization–tandem mass spectrometry method for the simultaneous quantitation of nicotinic acid (NicA) and its metabolites nicotinamide (NA), 1-methylnicotinamide (MNA), 1-methyl-2-pyridone-5-carboxamide (M2PY) and 1-methyl-4-pyridone-5-carboxamide (M4PY) in rat plasma has been developed and validated. As an internal standard, 6-chloronicotinamide was used. The samples (100?L) were subjected to deproteinization with acetonitrile (200?L) and then, after centrifugation, 150?L of the supernatant was transferred into conical vial and evaporated. Dry residue was reconstituted in 100?L of the ACN/water (10:90, v/v) mixture. Chromatography was performed on a Waters Spherisorb® 5?m CNRP 4.6?150mm analytical column with gradient elution using a mobile phase containing acetonitrile and water with 0.1% of formic acid. The full separation of all compounds was achieved within 15min of analysis. Detection was performed by an Applied Biosystems MDS Sciex API 2000 triple quadrupole mass spectrometer set at unit resolution. The mass spectrometer was operated in the selected reactions monitoring mode (SRM), monitoring the transition of the protonated molecular ions m/z 153–110 for M2PY, 153–136 for M4PY, 124–80 for NicA, 123–80 for NA and 137–94 for MNA. The mass spectrometric conditions were optimized for each compound by continuously infusing the standard solution at the rate of 5?L/min using a Harvard infusion pump. Electrospray ionization (ESI) was used for ion production. The instrument was coupled to an Agilent 1100 LC system. The precision and accuracy for both intra- and inter-day determination of all analytes ranged from 1.3% to 13.3% and from 94.43% to 110.88%. No significant matrix effect (ME) was observed. Stability of compounds was established in a battery of stability studies, i.e. bench-top, autosampler and long-term storage stability as well as freeze/thaw cycles. The method proved to be suitable for various applications. In particular using this method we detected increased concentration of MNA and its metabolites in rat plasma after treatment with exogenous MNA (100mg/kg), as well as increased concentration of endogenous NA and MNA in rat plasma in the early phase of hypertriglyceridemia development in rats fed high-fructose diet.

http://dx.doi.org/10.1016%2Fj.jchromb.2010.02.009

81. U15769
van der Ham M. et al. Liquid chromatography–tandem mass spectrometry assay for the quantification of free and total sialic acid in human cerebrospinal fluid // Journal of Chromatography B. 2010. Vol. 878, № 15. P. 1098–1102.

Analysis of sialic acid (SA) metabolites in cerebrospinal fluid (CSF) is important for clinical diagnosis. In the present study, a high-performance liquid chromatography–tandem mass spectrometry (HPLC/MS/MS) method for free sialic acid (FSA) and total sialic acid (TSA) in human CSF was validated. The method utilized a simple sample-preparation procedure of protein precipitation for FSA and acid hydrolysis for TSA. Negative electrospray ionisation was used to monitor the transitions m/z 308.2>87.0 (SA) and m/z 311.2>90.0 (13C3-SA). Conjugated sialic acid (CSA) was calculated by subtracting FSA from TSA. We established reference intervals for FSA, TSA and CSA in CSF in 217 control subjects. The method has been applied to patients’ samples with known differences in SA metabolites like meningitis (n=6), brain tumour (n=2), leukaemia (n=5), and Salla disease (n=1). Limit of detection (LOD) was 0.54?M for FSA and 0.45?M for TSA. Intra- and inter-assay variation for FSA (21.8?M) were 4.8% (n=10) and 10.4% (n=40) respectively. Intra- and inter-assay variation for TSA (35.6?M) were 9.7% (n=10) and 12.8% (n=40) respectively. Tested patients showed values of TSA above established reference value. The validated method allows sensitive and specific measurement of SA metabolites in CSF and can be applied for clinical diagnoses.

http://dx.doi.org/10.1016%2Fj.jchromb.2010.03.020

82. Villani C. Editors’ Note: Chirality in Separation Science and Molecular Recognition Honoring Prof. F. Gasparrini Thematic Issue 2016 // Chirality. 2016. Vol. 28, № 10. P. 708–708.

It is my great pleasure to present the thematic issue honoring professor Francesco Gasparrini on the occasion of his 70th birthday. The “Chirality in Separation Science and Molecular Recognition Honoring Prof. F. Gasparrini” special issue collects a number of original research papers and review works that broadly cover the different facets of chirality involved in separation science and in the molecular interactions that govern enantioselectivity in chromatographic systems and in supramolecular associations in general. Several contributions also include the determination of absolute configuration of chiral molecules by combined spectroscopy and calculation of chiroptical properties.

http://dx.doi.org/10.1002%2Fchir.22632

83. U01982
Wang Z. et al. Authentication of Organically and Conventionally Grown Basils by Gas Chromatography/Mass Spectrometry Chemical Profiles // Anal. Chem. 2013. Vol. 85, № 5. P. 2945–2953.

Basil plants cultivated by organic and conventional farming practices were accurately classified by pattern recognition of gas chromatography/mass spectrometry (GC/MS) data. A novel extraction procedure was devised to extract characteristic compounds from ground basil powders. Two in-house fuzzy classifiers, i.e., the fuzzy rule-building expert system (FuRES) and the fuzzy optimal associative memory (FOAM) for the first time, were used to build classification models. Two crisp classifiers, i.e., soft independent modeling by class analogy (SIMCA) and the partial least-squares discriminant analysis (PLS-DA), were used as control methods. Prior to data processing, baseline correction and retention time alignment were performed. Classifiers were built with the two-way data sets, the total ion chromatogram representation of data sets, and the total mass spectrum representation of data sets, separately. Bootstrapped Latin partition (BLP) was used as an unbiased evaluation of the classifiers. By using two-way data sets, average classification rates with FuRES, FOAM, SIMCA, and PLS-DA were 100 ± 0%, 94.4 ± 0.4%, 93.3 ± 0.4%, and 100 ± 0%, respectively, for 100 independent evaluations. The established classifiers were used to classify a new validation set collected 2.5 months later with no parametric changes except that the training set and validation set were individually mean-centered. For the new two-way validation set, classification rates with FuRES, FOAM, SIMCA, and PLS-DA were 100%, 93%, 97%, and 100%, respectively. Thereby, the GC/MS analysis was demonstrated as a viable approach for organic basil authentication. It is the first time that a FOAM has been applied to classification. A novel baseline correction method was used also for the first time. The FuRES and the FOAM are demonstrated as powerful tools for modeling and classifying GC/MS data of complex samples, and the data pretreatments are demonstrated to be useful to improve the performance of classifiers.

http://dx.doi.org/10.1021%2Fac303445v

84. U01982
Wang Z. et al. Authentication of Organically and Conventionally Grown Basils by Gas Chromatography/Mass Spectrometry Chemical Profiles // Anal. Chem. 2013. Vol. 85, № 5. P. 2945–2953.

Basil plants cultivated by organic and conventional farming practices were accurately classified by pattern recognition of gas chromatography/mass spectrometry (GC/MS) data. A novel extraction procedure was devised to extract characteristic compounds from ground basil powders. Two in-house fuzzy classifiers, i.e., the fuzzy rule-building expert system (FuRES) and the fuzzy optimal associative memory (FOAM) for the first time, were used to build classification models. Two crisp classifiers, i.e., soft independent modeling by class analogy (SIMCA) and the partial least-squares discriminant analysis (PLS-DA), were used as control methods. Prior to data processing, baseline correction and retention time alignment were performed. Classifiers were built with the two-way data sets, the total ion chromatogram representation of data sets, and the total mass spectrum representation of data sets, separately. Bootstrapped Latin partition (BLP) was used as an unbiased evaluation of the classifiers. By using two-way data sets, average classification rates with FuRES, FOAM, SIMCA, and PLS-DA were 100 ± 0%, 94.4 ± 0.4%, 93.3 ± 0.4%, and 100 ± 0%, respectively, for 100 independent evaluations. The established classifiers were used to classify a new validation set collected 2.5 months later with no parametric changes except that the training set and validation set were individually mean-centered. For the new two-way validation set, classification rates with FuRES, FOAM, SIMCA, and PLS-DA were 100%, 93%, 97%, and 100%, respectively. Thereby, the GC/MS analysis was demonstrated as a viable approach for organic basil authentication. It is the first time that a FOAM has been applied to classification. A novel baseline correction method was used also for the first time. The FuRES and the FOAM are demonstrated as powerful tools for modeling and classifying GC/MS data of complex samples, and the data pretreatments are demonstrated to be useful to improve the performance of classifiers.

http://dx.doi.org/10.1021%2Fac303445v

85. U15769
Xu X. (Sophia) et al. Liquid chromatography and tandem mass spectrometry for the quantitative determination of ixabepilone (BMS-247550, Ixempra™) in human plasma: Method validation, overcoming curve splitting issues and eliminating chromatographic interferences from degradants // Journal of Chromatography B. 2010. Vol. 878, № 5. P. 525–537.

A sensitive method was developed and validated for the measurement of ixabepilone (BMS-247550, Ixempra™) using a demethylated analogue of ixabepilone (BMS-212188) as an internal standard. A 0.050mL portion of each plasma sample was extracted with 0.450mL of acetonitrile containing the internal standard via protein precipitation. The supernatant was analyzed on a LC–MS/MS system. Chromatography was carried out on a 2.0mm?100mm YMC ODS-AQ 3?m column using an isocractic mobile phase consisting of acetonitrile:10mM ammonium acetate, pH 5.0 (70:30, v/v) at a flow rate of 0.30mL/min. The mass spectrometer was fitted with a TurboIonSpray® source and operated in negative ionization mode. Detection of ixabepilone and BMS-212188 were accomplished using multiple reaction monitoring (MRM) of precursor>product ion pairs of m/z 505.2>405.2, and 492.1>392.1, respectively. The assay range was 2.00–500ng/mL and was fitted to a 1/x2 weighted quadratic regression model. Replicate sample analysis indicated that intra- and inter-day accuracy and precision are within ±15.0%. The recovery of ixabepilone from 0.050mL of plasma containing 5.00 and 400ng/mL was greater than 94%. The method was demonstrated to be sensitive, selective and robust, and was successfully used to support clinical studies. This paper also discussed approaches used for resolving a curve splitting issue observed during quantitative analysis of ixabepilone in biological matrices. Finally, to adapt the methodology to pharmacokinetics of ixabepilone after oral administration, the potential interference of chemical degradants on the determination of ixabepilone was evaluated.

http://dx.doi.org/10.1016%2Fj.jchromb.2009.12.014

86. Zhao X., Chen L. Analysis of melamine in milk powder by using a magnetic molecularly imprinted polymer based on carbon nanotubes with ultra high performance liquid chromatography and tandem mass spectrometry // J. Sep. Sci. 2016. Vol. 39, № 19. P. 3775–3781.

A new magnetic molecularly imprinted polymer was coupled with ultra high performance liquid chromatography and tandem mass spectrometry for the selective determination of melamine in milk powder. The magnetic molecularly imprinted polymer has been prepared by using carbon nanotubes as the matrix, Fe3O4 particles as the magnetic ingredient, melamine as the template molecule, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker and polyvinylpyrrolidone as the dispersant. The polymer was characterized with scanning electron microscopy, Fourier transform infrared spectroscopy and a physical property measurement system. The isothermal adsorption, kinetics adsorption, and selectivity were studied to evaluate the rebinding properties of the magnetic molecularly imprinted polymer. Various parameters affecting the extraction efficiency such as the amount of polymer, extraction time, and eluting solution were evaluated. The limit of detection was 0.00075 mg/kg. The relative standard deviations of the intraday and interday precision are 0.4-2.7 and 2.3-5.1%, respectively. The proposed method was successfully applied to determine melamine in different milk powder samples from different provenances, and satisfactory recoveries of 89.0-95.6% were obtained. This method has great significance for quality control and is simple and suitable for the rapid determination of melamine in milk powder.

http://dx.doi.org/10.1002%2Fjssc.201600625

87. 035917
Аболин А., П.-Ф И. Современная препаративная флеш-хроматография. Часть 2 // Аналитика. 2012. Т. 7, № 6. С. 34–39.

В этой части статьи авторы предлагают методику подбора условий для препаративного выделения продуктов из ложных смесей.

https://elibrary.ru/item.asp?id=18195966

88. 035917
Аболин А., Пьер-Франсуа И. Современная препаративная флеш-хроматография. Часть I // Аналитика. 2012. Т. 5, № 4. С. 24–33.

Статья посвящена флеш-хроматографии - современному методу препаративной жидкостной хроматографии. Описано оборудование компании Interchim SA (Франция) как для классической флеш-хроматографии и ультрапро- изводительной флеш-очистки, так и самые современные приборы - так называемые флеш-кроссоверы.

https://elibrary.ru/item.asp?id=18195947

89. 001624
Алексенко С.С. Жидкостная хроматография с масс-спектрометрическим детектированием для определения отравляющих веществ и продуктов их деструкции // Журнал Аналитической Химии. 2012. Т. 67, № 2. С. 116-132.

В обзоре обобщены результаты применения высокоэффективной жидкостной хроматографии с масс-спектрометрическим детектированием (ВЭЖХ-МС) для определения отравляющих веществ и их продуктов деструкции за последние 13 лет, прошедших с момента ратификации Конвенции по запрещению разработки, производства, накопления и применения химического оружия и о его уничтожении (Конвенция). Приведены условия разделения и детектирования в различных вариантах ионизации соединений (электрораспыление, химическая ионизация при атмосферном давлении) и анализаторами (времяпролетный, тандемный масс-спектрометрический, тройной квадруполь, ионная ловушка). Приведены пределы обнаружения продуктов деструкции, описаны возможности идентификации соединений, используемые способы пробоподготовки образцов с помощью современных вариантов концентрирования (жидкостная микроэкстракция) и выделения (применение различных сорбентов, полимеров с молекулярной памятью). Рассмотрены особенности анализа методом ВЭЖХ-МС объектов окружающей среды (вода, почва), биожидкостей (моча, сыворотка крови). Акцент в обзоре сделан на определение продуктов деструкции и производных отравляющих веществ нервно-паралитического действия ? алкилфосфоновых кислот.

https://elibrary.ru/item.asp?id=17313314

90. 040493
Белова В.В. Комбинированные экстракционно-хроматографические процессы разделения и очистки веществ // Химическая технология. 2016. № 12. С. 554–559.

Проанализированы различные варианты комбинированных экстракционно-хроматографических методов разделения и очистки веществ. Проведенные численные исследования с помощью расчетной программы показали, что противоточно-циклический процесс в режиме хроматографии с подачей смеси веществ в первом цикле процесса, в отличие от обычной противоточной экстракции, позволяет разделить многокомпонентные смеси при проведении одной операции.

https://elibrary.ru/item.asp?id=27519137

91. 040493
Белова В.В. Комбинированные экстракционно-хроматографические процессы разделения и очистки веществ // Химическая технология. 2016. № 12. С. 554–559.

Проанализированы различные варианты комбинированных экстракционно-хроматографических методов разделения и очистки веществ. Проведенные численные исследования с помощью расчетной программы показали, что противоточно-циклический процесс в режиме хроматографии с подачей смеси веществ в первом цикле процесса, в отличие от обычной противоточной экстракции, позволяет разделить многокомпонентные смеси при проведении одной операции.

https://elibrary.ru/item.asp?id=27519137

92. 001889
Белякова Л.Д., Буряк А.К., Ларионов О.Г. Хроматография - Метод исследования химии поверхности и процессов на межфазных границах // Физикохимия поверхности и защита материалов. 2013. Т. 49, № 6. С. 551-574.

В статье рассмотрено применение газовой и жидкостной хроматографии к исследованию химии поверхности различных материалов. Даны примеры изучения адсорбционных процессов из газовых и жидких сред с применением хроматографического метода. Показано, что опираясь на полученную хроматографическим методом информацию о структуре материала, можно предсказывать закономерности хроматографического удерживания для молекул разной структуры и сорбентов разного типа. Хроматографический метод распространен на исследование наноматериалов и стабильных наночастиц. Показано, что химические свойства модифицированных наночастицами поверхностей могут быть успешно исследованы методами газовой и жидкостной хроматографии. Значительное внимание уделено молекулярно-статистическим расчетам адсорбции на углеродных сорбентах в вариантах газовой и жидкостной хроматографии. Продемонстрированы возможности метода для предсказания удерживания сорбатов разного типа и уточнения структурных параметров молекул. Новое направление - мицеллярная хроматография наночастиц рассмотрено с методической и препаративной точек зрения. Показаны возможности жидкостной хроматографии для разделения, в том числе препаративного, идентификации и классификации наночастиц

https://elibrary.ru/item.asp?id=20352610

93. 04504X
Белякова Л.Д., Коломиец Л.Н. Всероссийская научно-практическая конференция «ХРОМАТОГРАФИЯ - НАРОДНОМУ ХОЗЯЙСТВУ» // Сорбционные и хроматографические процессы. 2010. Vol. 10, № 5. P. 790–792.

C 19 по 23 апреля 2010г. в г. Дзержинске состоялась Всероссийская научно-практическая конференция ХРОМАТОГРАФИЯ – НАРОДНОМУ ХОЗЯЙСТВУ». Конференция организована Российской академией наук, Научнымсоветом РАН по физической химии, Учреждением Российской академии наук Институтом физической химии иэлектрохимии им. А.Н.Фрумкина РАН, Учреждением Российской академии наук Институтом химии высокочистых веществ РАН, ГОУ ВПО « Нижегородским государственным университетом им. Н.И. Лобачевского» и Нижегородской региональной общественной организацией «Наука».

https://elibrary.ru/item.asp?id=15265909

94. 042658
Борисов Р.С. Новый подход к применению масс-спектрометрии DART в сочетании с планарной хроматографией для анализа смесей органических соединений // Масс-Спектрометрия. 2017. Т. 14, № 1. С. 28–32.

Разработана десорбционная ячейка для регистрации масс-спектров DART с пластин для планарной хроматографии. На примере анализа фармацевтических субстанций и их смесей показано, что предложенный подход позволяет повысить чувствительность метода и добиться воспроизводимости регистрируемых масс-спектров и хроматограмм по выделенным ионам.

https://elibrary.ru/item.asp?id=28912427

95. 035917
Галактионова Л. Применение автоматической онлайн-ТФЭ-ВЭЖХ-МС/МС-системы для разработки нового метода анализа // Аналитика. 2013. № 6 (13). С. 44–51.

В последние годы для определения лекарственных веществ наиболее широко используется метод высокоэффективной жидкостной хроматографии, совмещенной с тандемной масс-спектрометрией. Образцы крови, плазмы, мочи и пр. представляют собой многокомпонентные смеси, содержащие значительное количество затрудняющих определение интерферирующих компонентов. В статье представлен обзор методов подготовки проб к МС/МС-анализу. Приводится пример эффективной технологии разработки нового метода анализа хинаприла и его метаболитов на автоматической онлайн-ТФЭ-ВЭЖХ-МС/МС-системе.

https://elibrary.ru/item.asp?id=20631221

96. 000477
Гендриксон О.Д. и др. Методы Детекции И Идентификации Техногенных Наночастиц // Биофизика. 2011. Т. 56, № 6. С. 965–994.

Представлен обзор современных методов детекции и идентификации техногенных наночастиц как в простых, так и в сложных многокомпонентных матриксах для оценки биологического действия и безопасности нанотехнологической продукции. Особое место уделено детекции приоритетных видов биологически активных наночастиц, к которым относятся фуллерены, одно- и многослойные углеродные нанотрубки, наночастицы серебра, золота, оксидов титана, алюминия, церия, цинка и кремния. Охарактеризованы требования, предъявляемые к пробоподготовке. Представлены результаты успешного применения для детекции техногенных наночастиц в биопробах методов сканирующей и просвечивающей электронной микроскопии, конфокальной лазерной сканирующей микроскопии, атомно-силовой микроскопии, сканирующей туннельной микроскопии, эксклюзионной хроматографии, проточного фракционирования в поперечном поле, электрофоретических, светорассеяния, спектрофотометрических, флуоресцентноспектральных, рентгеноспектральных и других спектрометрических, масс-спектрометрических, «счетчиков частиц», иммуно химических. Охарактеризованы возможности и ограничения разных методов, а также их взаимодополняемость

https://elibrary.ru/item.asp?id=17395064

97. 039763
Горшков А.В. et al. Критическая хроматография и масс-спектрометрия макромолекул: Определение места функциональной группы в цепи // Высокомолекулярные Соединения. Серия А. 2010. Т. 52, № 3. С. 478–486.

Рассмотрены возможности метода критической хроматографии макромолекул, дополненного методом масс-спектрометрии, для исследования наиболее сложной характеристики строения макромолекулы ? определения места (номера) дефектного звена или функциональной группы в последовательности звеньев цепи. В качестве объектов исследования использованы образцы полиуретанов на основе олигомеров полипропиленоксида. Такие макромолекулы содержат небольшое число уретановых групп в цепи, отличающихся по энергии взаимодействия с поверхностью от основных звеньев цепи. Варьирование молекулярно-массового распределения исходных олигомеров полипропиленоксида позволяет получать линейные макромолекулы полиуретанов с различным расположением уретановых групп в цепи. Критическая хроматография дает возможность разделить макромолекулы, различающиеся количеством уретановых групп и их местом в цепи.

https://elibrary.ru/item.asp?id=13726847

98. 000975
Горшков А.В. et al. Критическая хроматография и масс-спектрометрия макромолекул: Определение места функциональной группы в цепи // Высокомолекулярные Соединения. Серия А. 2010. Т. 52, № 3. С. 478–486.

Рассмотрены возможности метода критической хроматографии макромолекул, дополненного методом масс-спектрометрии, для исследования наиболее сложной характеристики строения макромолекулы ? определения места (номера) дефектного звена или функциональной группы в последовательности звеньев цепи. В качестве объектов исследования использованы образцы полиуретанов на основе олигомеров полипропиленоксида. Такие макромолекулы содержат небольшое число уретановых групп в цепи, отличающихся по энергии взаимодействия с поверхностью от основных звеньев цепи. Варьирование молекулярно-массового распределения исходных олигомеров полипропиленоксида позволяет получать линейные макромолекулы полиуретанов с различным расположением уретановых групп в цепи. Критическая хроматография дает возможность разделить макромолекулы, различающиеся количеством уретановых групп и их местом в цепи.

https://elibrary.ru/item.asp?id=13726847

99. 035917
Жохов С., Шахнович О. Всероссийский симпозиум “Разделение и концентрирование в аналитической химии и радиохимии”. Часть 2 // Аналитика. 2015. № 2 (21). С. 36–57.

Мы продолжаем обзор аналитического оборудования, которое российские и зарубежные компании представили в рамках симпозиума, состоявшегося осенью 2014 года на базе Кубанского университета. В этой части обзора мы расскажем главным образом о современных системах для элементного анализа, газовой хроматографии и хромато-масс-спектрометрии, рентгеновского сканирования поверхностей. В докладах симпозиума также освещались новейшие методологические подходы - непрерывная хроматография и капиллярный электрофорез с масс-спектрометрическим детектированием, было представлено оборудование для реализации этих методов в лабораторных условиях

https://elibrary.ru/item.asp?id=23199126

100. 04504X
Зайцева (баум) Е. А. К.И. Сакодынский (1930-1996) и хроматография. (К 80-летию со дня рождения) // Сорбционные и хроматографические процессы. 2011. Т. 11, № 1. С. 8–22.

Сакодынский является одним из тех, чьими усилиями хроматогратография в нашей стране ( имеется ввиду СССР ) получила интенсивное развитие, и одним из тех, кто главной целью своей научной жизни сделал содействие ее успехам». Немалое место в деятельности К.И.Сакодынского занимали вопросы истории хроматографии . Свыше 30 лет он занимался поиском материалов об основателе хроматографии М.С.Цвете.

https://elibrary.ru/item.asp?id=16497751

101. 04504X
Карпов С.И. и др. Перспективы синтеза и использования упорядоченных мезопористых материалов при сорбционно-хроматографическом анализе, разделении и концентрировании физиологически активных веществ (обзор) // Сорбционные и хроматографические процессы. 2013. Т. 13, № 2. С. 125–140.

Рассмотрены основные направления синтеза, модификации и применения мезопористых материалов с упорядоченной структурой мезопор в качестве эффективных сорбентов для концентрирования и разделения физиологически активных веществ (аминокислот, полифенолов, компонентов жирорастворимых витаминов). Представлен обзор публикаций по направлениям использования мезопористых композитов на основе МСМ-41 в хроматографии.

https://elibrary.ru/item.asp?id=19690621

102. 035917
Крылов A., Koнопелко Л. Определение полиароматических углеводородов методом газовой хроматографии - масс-спектрометрии с изотопным разбавлением (ГХ/МС/ИР) // Аналитика. 2012. Т. 4, № 3. С. 06-17.

Обобщены существующие методики измерения полиароматических углеводородов (ПАУ), используемые в практике работы аналитических лабораторий РФ. Приведены примеры использования метода газовой хроматографии – масс-спектрометрии с изотопным разбавлением (ГХ/МС/ИР) для определения ПАУ как в растворах, так и при анализе сложных матриц (почва, донные отложения, промышленная продукция и отходы). Показаны лучшие точностные характеристики метода ГХ/МС/ИР: достоверность идентификации, расширенная неопределенность измерений. Рааботаны методики измерений (МИ) на основе техники ГХ/МС/ИР, которые можно рассматривать как арбитражные по отношению к другим существующим методам анализа. Предложено рассматривать ГХ/МС/ИР в качестве метода высшей точности в сравнении с другими методами измерений ПАУ. Отмечена необходимость создания референтных материалов (на основе природных матриц различного типа) и внедрения их в практику для валидации имеющихся или разрабатываемых методик.

https://elibrary.ru/item.asp?id=18195938

103. 035917
Лебедев А. Россия может стать ведущей державой в области масс-спектрометрии // Аналитика. 2013. Т. 9, № 2. С. 10–23.

Масс-спектрометрия – одно из немногих направлений прикладной аналитики, успехи которой принципиально повлияли на множество прикладных областей и даже привели к появлению новых научных дисциплин. Современная масс-спектрометрия – это еще и направление индустриального приборостроения, в котором работают сотни компаний. Что немаловажно, многие успехи масс-спектрометрии связаны с деятельностью отечественных специалистов, но очень многие из них трудятся вне пределов России, на благо зарубежных фирм. В 2003 году в России было создано Всероссийское масс-спектрометрическое общество, призванное объединить специалистов. За прошедшие без малого 10 лет достигнуты определенные успехи, однако задач, которые предстоит решить, – гораздо больше. О достижениях и роли современной масс-спектрометрии, о проблемах развития этого направления в нашей стране нам рассказал президент Всероссийского масс-спектрометрического общества, заведующий лабораторией органического анализа МГУ Альберт Тарасович Лебедев.

https://elibrary.ru/item.asp?id=18915760

104. 000693
Москвин Л.Н., Якимова Н.М. Что Такое Хроматография? Какие Бывают Хроматографии? // Вестник Санкт-Петербургского Университета. Серия 4. Физика. Химия. 2015. Т. 2, № 3. С. 244–268.

Обосновывается необходимость найти ответ на вопрос, что такое хроматография, и привести в единую систему многочисленные хроматографические методы. Обсуждаются причины неоднозначного понимания термина «хроматография» с момента её открытия и до наших дней. На основании анализа истории развития хроматографии и смещения акцентов в понимании смысла этого термина предложены общие принципы систематизации хроматографических методов и варианты их классификации в зависимости от смысла, вкладываемого в сам термин «хроматография».

https://elibrary.ru/item.asp?id=24380702

105. 46377
Москвин Л.Н., Якимова Н.М. Что Такое Хроматография? Какие Бывают Хроматографии? // Вестник Санкт-Петербургского Университета. Серия 4. Физика. Химия. 2015. Т. 2, № 3. С. 244–268.

Обосновывается необходимость найти ответ на вопрос, что такое хроматография, и привести в единую систему многочисленные хроматографические методы. Обсуждаются причины неоднозначного понимания термина «хроматография» с момента её открытия и до наших дней. На основании анализа истории развития хроматографии и смещения акцентов в понимании смысла этого термина предложены общие принципы систематизации хроматографических методов и варианты их классификации в зависимости от смысла, вкладываемого в сам термин «хроматография».

https://elibrary.ru/item.asp?id=24380702

106. 035955
Нгуен К.З. Методы определения ароматических аминов в окружающей среде // Геология, География и Глобальная Энергия. 2011. № 2. С. 190–198.

Дан обзор по методам определения ароматических аминов из окружающей среды. Основным методом идентификации и количественного определения ароматических аминов является хроматография в самых различных вариантах.

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Оскотская Э.Р., Грибанов Е.Н. Очистка экстрактов проб зерновых культур алюмосиликатом при определении пестицидов методом газовой хроматографии с масс-спектрометрическим детектированием // Журнал Аналитической Химии. 2017. Т. 72, № 2. С. 170–176.

Предложена методика определения 23 пестицидов различных классов (фосфор- и хлорорганические, синтетические пиретроиды, триазолы) в зерновых культурах, основанная на пробоподготовке образцов по методу QuEChERS с последующими очисткой экстракта природным алюмосиликатом и определением аналитов методом газовой хроматографии с масс-спектрометрическим детектированием. Пределы количественного определения пестицидов ~0.005 мг/кг. Относительное стандартное отклонение не превышает 0.02. Продолжительность анализа 35–40 мин.

https://elibrary.ru/item.asp?id=28918458

108. Рудаков O.Б. Лидеры в области Separation Science по данным Российского индекса научного цитирования // Научный вестник Воронежского Государственного архитектурно-строительного университета. Серия: Физико-химические проблемы и высокие технологии строительного материаловедения. 2016. № 1 (12). С. 143–153.

Представлен анализ публикационных показателей докторов наук, работающих в области ионного обмена, мембранных, сорбционных, хроматографических и экстракционных процессов разделения по рейтингу национальной библиографической базы данных научного цитирования – Российского индекса научного цитирования.

https://elibrary.ru/item.asp?id=26286311

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Рудаков О.Б., Селеменев В.Ф. Российская хроматография - времена и люди // Сорбционные и хроматографические процессы. 2014. Т. 14, № 3. С. 384–396.

Рассмотрены этапы развития хроматографии и сложившиеся региональные хроматографические научные школы в России.

https://elibrary.ru/item.asp?id=21790442

110. 04504X
Сальников А.В., Мирошниченко Л.А., Епринцев А.Т. Ионообменная хроматография - необходимый этап для разделения изоферментов глиоксилатного цикла // Сорбционные и хроматографические процессы 2012. Т. 12, № 6. С. 989–997.

Применение ионообменной хроматографии на ДЕАЕ-целлюлозе позволило получить препараты изоферментов изоцитратлиазы и аконитатгидратазы из животных и растительных объектов в высокоочищенном электрофоретически гомогенном состоянии. Исследованы кинетические и фикико-химические свойства выделенных ферментов.

https://elibrary.ru/item.asp?id=18259064

111. 006651
Сидельников В.Н., Платонов И.А., Пармон В.Н. Газовая хроматография будущего: колонки, время которых пришло // Успехи химии. 2016. Т. 85, № 10. С. 1033–1055.

В настоящее время развивается новая технология приготовления хроматографических колонок, основанная на методах, которые разработаны для создания микроэлектромеханических систем. Данная технология позволяет уменьшить габариты колонки, а также открывает перспективы для создания уникальной технологии производства колонок без участия человека. В обзоре приведены данные по применению такой технологии для создания газохроматографических капиллярных колонок. Рассмотрены способы получения капилляров, влияние их формы и конфигурации на хроматографические свойства колонок. Обсуждены способы внесения неподвижных фаз в капилляры, основанные на традиционных для капиллярной газовой хроматографии методах и методах, заимствованных из полупроводниковых и микроэлектромеханических технологий. Рассмотрены уникальные свойства полунасадочных колонок, полученных с использованием микроэлектромеханических технологий. Обсуждены возможные области применения таких колонок и пути их дальнейшего развития. Библиография - 179 ссылок.

https://elibrary.ru/item.asp?id=26719821

112. Токарь А.Ю. Мембранные процессы разделения // Международный научно-исследовательский журнал. 2014. № 1–1 (20). С. 94–96.

В статье рассмотрена сущность мембранных процессов разделения через знакомство с основными публикациями в периодических научных изданиях, ознакомление с учебно-методической литературой по данной тематике.

https://elibrary.ru/item.asp?id=21181324

113. 035917
Хорошко Л. и др. Прямое определение трибутилолова хлорида в донных отложениях Финского залива методом газовой хроматографии/масс-спектрометрии // Аналитика. 2012. Т. 6, № 5. С. 30–35.

Органические соединения олова интенсивно используются в быту и промышленности во всем мире с 60-х годов прошлого столетия благодаря своим биоцидным свойствам. Авторы исследовали содержание трибутилолова хлорида в российской части акватории Финского залива.

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Цюрупа М.П., Блинникова З.К., Даванков В.А. Эксклюзионная хроматография минеральных электролитов на нейтральном нанопористом сверхсшитом полистироле: механизм «задерживания» кислот, солей и оснований // Сорбционные и хроматографические процессы. 2013. Т. 13, № 5. С. 541–552.

Описаны основные принципы нового метода фронтальной препаративной эксклюзионной хроматографии минеральных электролитов на нейтральном нанопористом сверхсшитом полистирольном сорбенте NanoNet-381 промышленного производства. Дано объяснение общего для нейтральных сорбентов и ионообменных смол механизма процесса задерживания кислот (acid retardation) и приведены примеры аналогичных по механизму новых процессов задерживания солей и оснований.

https://elibrary.ru/item.asp?id=20725255

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Шапошник В.А. 110 лет открытия хроматографии М.С. Цветом // Сорбционные и хроматографические процессы. 2013. Т. 13, № 6. С. 741–750.

Проведён анализ первой работы М.С. Цвета 1903 г., в которой была впервые высказана идея хроматографии. На примере открытия хроматографии рассмотрены объективные причины сопротивления научного сообщества новым идеям, которые не соответствуют сложившейся парадигме. Описаны недолгие годы жизни М.С. Цвета в Воронеже. Изложено превращения хроматографии в самый информативный метод химического анализа.

https://elibrary.ru/item.asp?id=20922401

116. 04504X
Яшин Я.И. Основные тенденции развития хроматографии после 110-летия со дня ее открытия М.С.Цветом // Сорбционные и хроматографические процессы. 2014. Т. 14, № 2. С. 203–213.

На основании анализа материалов конференций и симпозиумов по хроматографии за 2010-2013 г.г., а также анализа публикаций (обзоров и статей) выявлены основные направления развития методов и аппаратуры для хроматографии, а также их новые области применения.

https://elibrary.ru/item.asp?id=21481495

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