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Dong X, Wang R, Zhou X, Li P, Yang H. Current mass spectrometry approaches and challenges for the bioanalysis of traditional Chinese medicines. J Chromatogr B Analyt Technol Biomed Life Sci 2016; 1026:15-26. [DOI: 10.1016/j.jchromb.2015.11.048] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 11/23/2015] [Accepted: 11/25/2015] [Indexed: 12/11/2022]
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2
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Waseem R, Low KH. Advanced analytical techniques for the extraction and characterization of plant-derived essential oils by gas chromatography with mass spectrometry. J Sep Sci 2015; 38:483-501. [DOI: 10.1002/jssc.201400724] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 10/22/2014] [Accepted: 11/06/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Rabia Waseem
- Centre for Natural Product Research and Drug Discovery; Department of Chemistry; University of Malaya; Kuala Lumpur Malaysia
| | - Kah Hin Low
- Centre for Natural Product Research and Drug Discovery; Department of Chemistry; University of Malaya; Kuala Lumpur Malaysia
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3
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Kalili KM, de Villiers A. Systematic optimisation and evaluation of on-line, off-line and stop-flow comprehensive hydrophilic interaction chromatography×reversed phase liquid chromatographic analysis of procyanidins, Part I: Theoretical considerations. J Chromatogr A 2013; 1289:58-68. [DOI: 10.1016/j.chroma.2013.03.008] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2012] [Revised: 02/13/2013] [Accepted: 03/08/2013] [Indexed: 02/04/2023]
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4
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Mostafa A, Edwards M, Górecki T. Optimization aspects of comprehensive two-dimensional gas chromatography. J Chromatogr A 2012; 1255:38-55. [DOI: 10.1016/j.chroma.2012.02.064] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 02/21/2012] [Accepted: 02/24/2012] [Indexed: 11/16/2022]
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5
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Luong J, Cai H, Gras R, Curvers J. Developments in Ultra-Fast Temperature Programming with Silicon Micromachined Gas Chromatography: Performance and Limitations. J Chromatogr Sci 2012; 50:245-52. [DOI: 10.1093/chromsci/bmr052] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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6
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Osiri JK, Shadpour H, Witek MA, Soper SA. Integrated multifunctional microfluidics for automated proteome analyses. Top Curr Chem (Cham) 2011; 304:261-94. [PMID: 21678138 DOI: 10.1007/128_2011_152] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Proteomics is a challenging field for realizing totally integrated microfluidic systems for complete proteome processing due to several considerations, including the sheer number of different protein types that exist within most proteomes, the large dynamic range associated with these various protein types, and the diverse chemical nature of the proteins comprising a typical proteome. For example, the human proteome is estimated to have >10(6) different components with a dynamic range of >10(10). The typical processing pipeline for proteomics involves the following steps: (1) selection and/or extraction of the particular proteins to be analyzed; (2) multidimensional separation; (3) proteolytic digestion of the protein sample; and (4) mass spectral identification of either intact proteins (top-down proteomics) or peptide fragments generated from proteolytic digestions (bottom-up proteomics). Although a number of intriguing microfluidic devices have been designed, fabricated and evaluated for carrying out the individual processing steps listed above, work toward building fully integrated microfluidic systems for protein analysis has yet to be realized. In this chapter, information will be provided on the nature of proteomic analysis in terms of the challenges associated with the sample type and the microfluidic devices that have been tested to carry out individual processing steps. These include devices such as those for multidimensional electrophoretic separations, solid-phase enzymatic digestions, and solid-phase extractions, all of which have used microfluidics as the functional platform for their implementation. This will be followed by an in-depth review of microfluidic systems, which are defined as units possessing two or more devices assembled into autonomous systems for proteome processing. In addition, information will be provided on the challenges involved in integrating processing steps into a functional system and the approaches adopted for device integration. In this chapter, we will focus exclusively on the front-end processing microfluidic devices and systems for proteome processing, and not on the interface technology of these platforms to mass spectrometry due to the extensive reviews that already exist on these types of interfaces.
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Affiliation(s)
- John K Osiri
- Department of Chemistry, Louisiana State University, Baton Rouge, LA 70817, USA
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7
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Julka S, Cortes H, Harfmann R, Bell B, Schweizer-Theobaldt A, Pursch M, Mondello L, Maynard S, West D. Quantitative characterization of solid epoxy resins using comprehensive two dimensional liquid chromatography coupled with electrospray ionization-time of flight mass spectrometry. Anal Chem 2009; 81:4271-9. [PMID: 19402677 DOI: 10.1021/ac9001047] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A comprehensive multidimensional liquid chromatography system coupled to Electrospray Ionization-Mass Spectrometry (LCxLC-ESI-MS) was developed for detailed characterization and quantitation of solid epoxy resin components. The two orthogonal modes of separation selected were size exclusion chromatography (SEC) in the first dimension and liquid chromatography at critical conditions (LCCC) in the second dimension. Different components present in the solid epoxy resins were separated and quantitated for the first time based on the functional groups and molecular weight heterogeneity. Coupling LCxLC separations with mass spectrometry enabled the identification of components resolved in the two-dimensional space. Several different functional group families of compounds were separated and identified, including epoxy-epoxy and epoxy-alpha-glycol functional oligomers, and their individual molecular weight ranges were determined. Repeatability obtained ranged from 0.5% for the main product to 21% for oligomers at the 0.4% concentration level.
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Affiliation(s)
- Samir Julka
- The Dow Chemical Company, Analytical Sciences, 1897 Building, Midland, Michigan 48667, USA
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8
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Cortes HJ, Winniford B, Luong J, Pursch M. Comprehensive two dimensional gas chromatography review. J Sep Sci 2009; 32:883-904. [DOI: 10.1002/jssc.200800654] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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9
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Shellie RA, Tyrrell E, Pohl CA, Haddad PR. Column selection for comprehensive multidimensional ion chromatography. J Sep Sci 2008; 31:3287-96. [PMID: 18803256 DOI: 10.1002/jssc.200800286] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This paper discusses the selection of ion chromatography (IC) columns for use in comprehensive multidimensional ion chromatography (IC x IC). First, a single number was determined for a wide range of anions (one number for each anion) using the linear solvent strength model. These numbers were then used to compare the column selectivity characteristics for five different columns. Principal component analysis was used to illustrate selectivity differences between columns. Dionex AS16 and AS20 columns were selected for use in the development of an IC x IC method for the separation of ten anions. To achieve the required speed of analysis in both the first and second separation dimensions, custom column lengths were packed in-house. The use of an eluent suppressor between the first and second columns permits a relatively low flow ratio regime of only <1:20 in the first and second dimensions, respectively, which reduces dilution effects common in comprehensive multidimensional LC. Selection of the second dimension eluent conditions was aided by the development of a spreadsheet based on the linear solvent strength model.
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Affiliation(s)
- Robert A Shellie
- Australian Centre for Research on Separation Science, School of Chemistry, University of Tasmania, Hobart, Australia
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10
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Mondello L, Herrero M, Kumm T, Dugo P, Cortes H, Dugo G. Quantification in comprehensive two-dimensional liquid chromatography. Anal Chem 2008; 80:5418-24. [PMID: 18517223 DOI: 10.1021/ac800484y] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Although the use of comprehensive two-dimensional liquid chromatography (LCxLC) as a powerful separation technique is continuously increasing, its employment in quantification experiments is rather limited. The present research is focused on the quantification of a series of standards, as well as real-world sample compounds, by using dedicated laboratory-constructed LCxLC software, developed through a novel approach. Moreover, the difficulties encountered during software operation, in various elution conditions, are described and discussed. The results attained were compared with those observed in conventional LC, and no statistically significant differences were observed in the determination of aurapten in grapefruit oil. However, a loss in sensitivity was observed when using LCxLC (limit of detection = 0.10 ppm) compared to conventional LC (limit of detection = 0.05 ppm) as a consequence of the sample dilution in comprehensive two-dimensional liquid chromatography.
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Affiliation(s)
- Luigi Mondello
- Dipartimento Farmaco-chimico, Facoltà di Farmacia, Università di Messina, Viale Annunziata, 98168, Messina, Italy.
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11
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Development of a comprehensive multidimensional liquid chromatography system with tandem mass spectrometry detection for detailed characterization of recombinant proteins. J Chromatogr A 2008; 1189:183-95. [DOI: 10.1016/j.chroma.2007.11.031] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 10/12/2007] [Accepted: 11/09/2007] [Indexed: 11/21/2022]
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12
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Dugo P, Cacciola F, Kumm T, Dugo G, Mondello L. Comprehensive multidimensional liquid chromatography: Theory and applications. J Chromatogr A 2008; 1184:353-68. [PMID: 17655853 DOI: 10.1016/j.chroma.2007.06.074] [Citation(s) in RCA: 231] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Revised: 06/27/2007] [Accepted: 06/28/2007] [Indexed: 11/23/2022]
Abstract
Comprehensive two-dimensional (2D) liquid chromatographic (LC x LC) techniques can be considered innovative methods only recently developed and adopted in many configurations. The revolutionary aspect of comprehensive two-dimensional techniques, with respect to classical multidimensional (MD) chromatography, is that the entire sample is subjected to the 2D advantage. The major benefit is that the separation capacities of each dimension are multiplied, offering a high peak capacity to resolve samples of great complexity. The first part of the present review briefly describes the theoretical and practical aspects related to the development of a multidimensional comprehensive liquid chromatographic method. Applicational experiences in comprehensive liquid chromatography are then described, divided into four groups, according to the HPLC modes used in the two dimensions and to the nature of the samples analyzed.
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Affiliation(s)
- Paola Dugo
- Dipartimento di Scienza degli alimenti e dell'ambiente, Facoltà di Scienze, Università di Messina, Salita Sperone 31, 98166 Messina, Italy.
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13
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Mikulíková K, Eckhardt A, Pataridis S, Mikšík I. Study of posttranslational non-enzymatic modifications of collagen using capillary electrophoresis/mass spectrometry and high performance liquid chromatography/mass spectrometry. J Chromatogr A 2007; 1155:125-33. [DOI: 10.1016/j.chroma.2007.01.020] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2006] [Revised: 12/18/2006] [Accepted: 01/05/2007] [Indexed: 01/22/2023]
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14
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Flores G, Ruiz Del Castillo ML, Herraiz M. Absorbents as packing materials in on-line coupling of reversed phase liquid chromatography and gas chromatography via a programmed temperature vaporizer. J Chromatogr A 2007; 1153:29-35. [PMID: 17306811 DOI: 10.1016/j.chroma.2007.01.128] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2006] [Revised: 01/13/2007] [Accepted: 01/18/2007] [Indexed: 10/23/2022]
Abstract
A method based on the use of absorbents as packing materials in the interface of the direct coupling between reversed phase liquid chromatography and gas chromatography (RPLC-GC) is proposed. To that end, a comparative study on different adsorbents and absorbents was carried out. Specifically, Tenax TA and Gaschrom were used as adsorbents while polydimethylsiloxane and poly(50% phenyl:50% methylsiloxane) were the absorbents tested. Some experimental variables involved in the solvent elimination were separately optimised for adsorbent and absorbent materials. Relative standard deviations (RSD) lower than 10% were achieved in all cases but the use of absorbents showed interesting advantages with respect to adsorbents, namely a simpler performance of the experimental work, which facilitates the sample preparation step and the subsequent gas chromatographic analysis to be performed.
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Affiliation(s)
- Gema Flores
- Instituto de Fermentaciones Industriales, Consejo Superior de Investigaciones Científicas (CSIC), c/ Juan de la Cierva 3, 28006 Madrid, Spain
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15
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Sweeney AP, Wyllie SG, Shalliker RA. THE SEPARATION OF STEREOISOMERS FROM OLIGOMERS OF LOW MOLECULAR WEIGHT POLYSTYRENE ON A CARBON CLAD ZIRCONIA COLUMN USING A REVERSED PHASE MULTIDIMENSIONAL HPLC SYSTEM. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-100106086] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Alan P. Sweeney
- a Centre for Biostructural and Biomolecular Research, University of Western Sydney , Locked Bag 1797, South Penrith Distribution Centre, NSW, 1797, Australia
| | - S. Grant Wyllie
- a Centre for Biostructural and Biomolecular Research, University of Western Sydney , Locked Bag 1797, South Penrith Distribution Centre, NSW, 1797, Australia
| | - R. Andrew Shalliker
- b Centre for Biostructural and Biomolecular Research, University of Western Sydney , Locked Bag 1797, South Penrith Distribution Centre, NSW, 1797, Australia
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Cacciola F, Jandera P, Blahová E, Mondello L. Development of different comprehensive two dimensional systems for the separation of phenolic antioxidants. J Sep Sci 2006; 29:2500-13. [PMID: 17154131 DOI: 10.1002/jssc.200600213] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Three different comprehensive 2-D HPLC systems for the separation of phenolic antioxidants have been developed on the basis of different selectivities of a PEG-silica column in the first dimension and a packed or monolithic C18 or a ZR-CARBON column, respectively, in the second dimension. Two-dimensional comprehensive liquid chromatography using a serially connected short PEG-silica column and a conventional C18-silica or a ZR-CARBON column in the second dimension was tested to improve the resolution of the earlier eluting compounds in the first dimension. Various types of interface were used to connect the columns in the first and in the second dimension: i) two injection sampling loops of 100 microL in conventional arrangement; ii) a 10-port 2-position valve equipped with two trapping X-Terra columns instead of loops; and iii) two analytical D2 columns in parallel. The mobile phase in the first dimension has a lower elution strength than in the second dimension, allowing band compression of the solutes transferred from the first to the second dimension. This effect was enhanced using trapping columns instead of sampling loops as the interface between the two dimensions, thus allowing a decrease in the time of analysis. These systems were used for the analysis of beer samples. The relative location of the components in the 2-D retention plane varied in relation to their chemical structure in each instrumental set-up and allowed positive peak identification.
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Affiliation(s)
- Francesco Cacciola
- Department of Analytical Chemistry, University of Pardubice, Pardubice, Czech Republic
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17
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Dugo P, Skeriková V, Kumm T, Trozzi A, Jandera P, Mondello L. Elucidation of Carotenoid Patterns in Citrus Products by Means of Comprehensive Normal-Phase × Reversed-Phase Liquid Chromatography. Anal Chem 2006; 78:7743-50. [PMID: 17105167 DOI: 10.1021/ac061290q] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A novel approach for carotenoid analysis has been developed. Orange essential oil and juice carotenoids were separated by means of comprehensive dual-gradient elution HPLC, using normal phase with a microbore silica column in the first dimension (first D), reversed phase with a monolithic C18 column in the second dimension (second D), and a 10-port switching valve as an interface. An on-line photodiode array detector was used in order to obtain absorption spectra. Peak identification was obtained by combining retention data with the UV-visible spectra.
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Affiliation(s)
- Paola Dugo
- Dipartimento di Scienze degli Alimenti e dell'Ambiente, Facoltà di Scienze MM.FF.NN., Università di Messina, Salita Sperone, 98166 Messina, Italy
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18
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Shellie RA, Haddad PR. Comprehensive two-dimensional liquid chromatography. Anal Bioanal Chem 2006; 386:405-15. [PMID: 16927069 DOI: 10.1007/s00216-006-0516-0] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Revised: 04/19/2006] [Accepted: 04/25/2006] [Indexed: 10/24/2022]
Abstract
Having nearly exhausted the possibilities for generating peak capacity through improvements in column technology, chromatographers are increasingly looking to alternative ways of maximising chromatographic separation. In recent years there has been increasing activity in the field of comprehensive multidimensional separations to meet analysis demands. Comprehensive two-dimensional liquid chromatography (LCxLC) approaches offer high peak capacity which leads to significantly improved analytical performance over single-column liquid chromatography. There are several closely related avenues available for achieving an LCxLC separation and this review pays special attention to the different valve-based interfaces that have been used to comprehensively couple the first and second dimension columns in LCxLC systems. A brief discussion of column choices for selected applications and the conditions employed is also presented.
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Affiliation(s)
- Robert A Shellie
- Australian Centre for Research on Separation Science (ACROSS), School of Chemistry, University of Tasmania, Private Bag 75, Hobart, 7001, Australia.
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Dugo P, Kumm T, Chiofalo B, Cotroneo A, Mondello L. Separation of triacylglycerols in a complex lipidic matrix by using comprehensive two-dimensional liquid chromatography coupled with atmospheric pressure chemical ionization mass spectrometric detection. J Sep Sci 2006; 29:1146-54. [PMID: 16830730 DOI: 10.1002/jssc.200500476] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The present investigation describes the employment of a comprehensive 2-D HPLC system, based on the combination of a silver ion and an RP column, for the characterization of the triacylglycerol (TAG) fraction of a very complex lipidic sample: donkey milk fat. The TAGs were grouped on the resulting bidimensional contour plot according to their double bond numbers (aligned along vertical bands) and according to their partition numbers (aligned along horizontal bands). Peak assignment was supported by using atmospheric pressure chemical ionization mass spectrometric (APCI-MS) detection. The combination of the enhanced resolving power of comprehensive multidimensional LC, the formation of ordered 2-D patterns, and APCI-MS detection proved to be an effective tool for the characterization of the complex matrix, enabling the separation and identification of nearly 60 TAGs.
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Affiliation(s)
- Paola Dugo
- Dipartimento di Chimica Organica e Biologica, Facoltà di Scienze, Università di Messina, Italy
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Mikulíková K, Eckhardt A, Miksík I. Posttranslational modifications of collagen studied by off-line coupling of HPLC and CE. J Sep Sci 2006; 29:1126-31. [PMID: 16830727 DOI: 10.1002/jssc.200500398] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A typical example of non-enzymatic change of collagen is glycation (the Maillard reaction, formation of advanced glycation end products) resulting from the reaction of sugars with the epsilon-amino group of lysine. Posttranslational non-enzymatic modifications of collagen by sugars were studied. Collagenous tissues were incubated as a test protein separately with both glucose and ribose. The collagen mixture was digested by bacterial collagenase and separated by reversed-phase HPLC (in a Jupiter Proteo 90 A column). The eluate from this HPLC separation was collected as seven fractions and consecutively analysed by CE in a bare fused silica capillary (57/50 cm x 75 mm id) using 100 mM sodium 1-heptanesulfonate in 100 mM phosphate buffer, pH 2.5 (NaH2PO4 adjusted to pH by phosphoric acid). The chromatographic and electromigration behaviour of individual peptides varied considerably. This off-line HPLC-CE coupling made it possible to discover minor changes in the structure of collagen caused by posttranslational modifications. A new HPLC-CE technique for peptide analysis was developed, and applied to the identification of posttranslational modifications in slowly metabolised test proteins.
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Shadpour H, Soper SA. Two-Dimensional Electrophoretic Separation of Proteins Using Poly(methyl methacrylate) Microchips. Anal Chem 2006; 78:3519-27. [PMID: 16737203 DOI: 10.1021/ac0600398] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The work presented herein describes highly efficient, two-dimensional (2D) electrophoretic separations of proteins in a PMMA-based microchip. Sodium dodecyl sulfate microcapillary gel electrophoresis (SDS micro-CGE) and micellar electrokinetic chromatography (MEKC) were used as the separation modes for the first and second dimension of the electrophoresis, respectively. The microchip was prepared by hot embossing into PMMA from a brass mold master fabricated via high-precision micromilling. The microchip incorporated a 30-mm SDS micro-CGE and a 10-mm MEKC dimension length. Electrokinetic injection and separation were used with field strengths of up to 400 V/cm. Alexa Fluor 633 conjugated proteins, ranging in size from 38 to 110 kDa, were detected using laser-induced fluorescence with excitation/emission at 633/652 nm. Average plate numbers (N) of 4.8 x 10(4) and 1.2 x 10(4) were obtained in the SDS micro-CGE and MEKC separation dimensions, respectively, for the investigated proteins corresponding to plate heights (H) of 0.62 and 0.87 microm. Effluents from the first dimension (SDS micro-CGE) were repetitively transferred into the second dimension every 0.5 s of run time in the first dimension with the electrophoresis run time in the MEKC dimension being 10 s. The 2D separation was performed on the investigated proteins in approximately 12 min and provided a peak capacity of approximately 1000.
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Affiliation(s)
- Hamed Shadpour
- Department of Chemistry and Center for BioModular Multi-Scale Systems, Louisiana State University, Baton Rouge, Louisiana 70803, USA
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Mondello L, Tranchida PQ, Stanek V, Jandera P, Dugo G, Dugo P. Silver-ion reversed-phase comprehensive two-dimensional liquid chromatography combined with mass spectrometric detection in lipidic food analysis. J Chromatogr A 2005; 1086:91-8. [PMID: 16130659 DOI: 10.1016/j.chroma.2005.06.017] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
The triacylglycerol (TAG) profiles present in real world lipidic samples are usually quite complex and, as such, monodimensional high-performance liquid chromatographic (HPLC) techniques are inadequate when challenged with such matrices. In this respect, the complementary use of silver-ion (Ag) and non-aqueous (NA) reversed-phase (RP) HPLC can be exploited if thorough TAG separations are required. The present investigation reports the employment of a newly developed comprehensive LC (LC x LC) system, based on the different separation mechanisms of the aforementioned techniques, and applied to a rice oil sample. The approach was successful in the separation of a high number of solutes, otherwise unachievable through monodimensional LC. Furthermore, the use of atmospheric pressure chemical ionization mass spectrometry (APCI-MS), as detection system, provided a third analytical dimension boosting the identification power of the comprehensive chromatographic method.
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Affiliation(s)
- L Mondello
- Dipartimento Farmaco-Chimico, Facoltá di Farmacia, Universitá di Messina, viale Annunziata, 98168 Messina, Italy
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Popovici ST, van der Horst A, Schoenmakers PJ. Two-dimensional chromatography as a tool for studying band broadening in size-exclusion chromatography. J Sep Sci 2005. [DOI: 10.1002/jssc.200400088] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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25
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Dugo P, Favoino O, Presti ML, Luppino R, Dugo G, Mondello L. Deterrmination of anthocyanins and related components in red wines by micro- and capillary HPLC. J Sep Sci 2004; 27:1458-66. [PMID: 15638153 DOI: 10.1002/jssc.200401822] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Anthocyanins and derived components of red wines were determined by microHPLC using a 1 mm ID HPLC column coupled on-line with an MS detector equipped with an ESI (ElectroSpray Ionisation) source. The use of microcolumn HPLC greatly enhanced detection performance, allowing direct identification of components present in the fraction. Nineteen anthocyanins were detected. Fifteen were identified, two were tentatively identified, and only the aglycon of the remaining two components was certainly identified. Six anthocyanin-derived pigments, supposedly formed during wine maturation, were also investigated and found in a wine sample. The analysis of red wine anthocyanins was also carried out by injecting a large sample volume onto a 0.32 mm ID HPLC column, using the column focusing technique, in order to decrease the limit of detection and quantification of components present in a very small amounts.
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Affiliation(s)
- Paola Dugo
- Dipartimento di Chimica Organica e Biologica, Facoltà di Scienze, Università di Messina, salita Sperone 31, 98166 Messina, Italy
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Dugo P, Favoino O, Luppino R, Dugo G, Mondello L. Comprehensive Two-Dimensional Normal-Phase (Adsorption)−Reversed-Phase Liquid Chromatography. Anal Chem 2004; 76:2525-30. [PMID: 15117193 DOI: 10.1021/ac0352981] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A comprehensive two-dimensional HPLC system has been developed. It is based on the use of a microbore silica column operated in normal-phase (adsorption) mode (NP) in the first dimension and a monolithic type C18 column operated in reversed-phase (RP) mode in the second dimension. The interface was a 10-port, 2-position valve equipped with two storage loops. The first column was operated at a flow rate of 20 microL/min in isocratic mode, while the monolithic column flow rate was 4 mL/min and was operated in gradient mode. The sample loops had a volume of 20 microL each, and the analysis time in the second dimension was 1 min. In this way, every fraction from the first dimension was transferred on-line to the second dimension switching the automated valve every minute. A photodiode array detector has been used after the secondary column. The use of normal- and reversed-phase mode in the two dimensions can be helpful in the separation of complex mixtures of a natural origin that contain uncharged molecules of comparable dimension, different in polarity and hydrophobicity. The use of a microbore column in the first dimension permits the injection of a small volume in the secondary column, making the transfer of incompatible solvents from the first to the second dimension possible. Since the mobile phase in the NP separation is always stronger than the mobile phase at the head of the secondary column operated in RP mode, the initial eluent strength is important in order to obtain an effective focusing of the sample. The use of a monolithic type column in the second dimension permits the performance of very fast analysis operating at higher flow rates without loss of resolution, due to a higher permeability and increased mass-transfer properties in comparison to conventional particulate columns. Due to the brief reconditioning time necessary for monolithic columns, repetitive gradients can be carried out, extending the field of application to mixtures that contain components with different polarities. The utility of the system has been demonstrated in the analysis of the oxygen heterocyclic fraction of cold-pressed lemon oil, made up of coumarins and psoralens. These components may contain hydroxyl, methoxyl, isopentenyl, isopentenyloxyl, and geranyloxyl groups and oxygen-containing modification of the terpenoid side-chain groups, such as epoxides or vicinal diol groups. The relative location of the components in the 2D plane varied in relation to their chemical structure and allowed positive peak identification. The UV spectra recorded with the photodiode array detector supplied additional information that was used for the characterization of the studied sample.
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Affiliation(s)
- Paola Dugo
- Dipartimento di Chimica Organica e Biologica, Facoltà di Scienze, Università di Messina, salita Sperone 31, 98166 Messina, Italy
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van der Horst A, Schoenmakers PJ. Comprehensive two-dimensional liquid chromatography of polymers. J Chromatogr A 2003; 1000:693-709. [PMID: 12877195 DOI: 10.1016/s0021-9673(03)00495-3] [Citation(s) in RCA: 201] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The need for and the emergence of comprehensive two-dimensional liquid chromatographic separations of synthetic polymers are reviewed in this paper. LC x SEC is shown to be a particularly valuable two-dimensional technique in this domain. An improved (symmetrical) configuration based on a single 10-way switching valve is described. The use of LC x SEC to understand and optimize one-dimensional separations is illustrated, as well as the potential of the technique for the separation and characterization of functional polymers and copolymers.
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Affiliation(s)
- Aschwin van der Horst
- Polymer-Analysis Group, Department of Chemical Engineering, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WVAmsterdam, The Netherlands
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28
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Walcher W, Oberacher H, Troiani S, Hölzl G, Oefner P, Zolla L, Huber CG. Monolithic capillary columns for liquid chromatography-electrospray ionization mass spectrometry in proteomic and genomic research. J Chromatogr B Analyt Technol Biomed Life Sci 2002; 782:111-25. [PMID: 12458001 DOI: 10.1016/s1570-0232(02)00667-0] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Peptides, proteins, single-stranded oligonucleotides, and double-stranded DNA fragments were separated with high resolution in micropellicular, monolithic capillary columns prepared by in situ radical copolymerization of styrene and divinylbenzene. Miniaturized chromatography both in the reversed-phase and the ion-pair reversed-phase mode could be realized in the same capillary column because of the nonpolar character of the poly-(styrene/divinylbenzene) stationary phase. The high chromatographic performance of the monolithic stationary phase facilitated the generation of peak capacities for the biopolymers in the range of 50-140 within 10 min under gradient elution conditions. Employing volatile mobile phase components, separations in the two chromatographic separation modes were on-line hyphenated to electrospray ionization (tandem) mass spectrometry, which yielded intact accurate molecular masses as well as sequence information derived from collision-induced fragmentation. The inaccuracy of mass determination in a quadrupole ion trap mass spectrometer was in the range of 0.01-0.02% for proteins up to a molecular mass of 20000, and 0.02-0.12% for DNA fragments up to a molecular mass of 310000. High-performance liquid chromatography-electrospray ionization mass spectrometry utilizing monolithic capillary columns was applied to the identification of proteins by peptide mass fingerprinting, tandem mass spectrometric sequencing, or intact molecular mass determination, as well as to the accurate sizing of double-stranded DNA fragments ranging in size from 50 to 500 base pairs, and to the detection of sequence variations in DNA fragments amplified by the polymerase chain reaction.
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Affiliation(s)
- Wolfgang Walcher
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens-University, A-6020 Innsbruck, Austria
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29
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Patrick DW, Strand DA, Cortes HJ. Automation and optimization of multidimensional microcolumn size exclusion chromatography-liquid chromatography for the analysis of photocrosslinkers in Cyclotene 4000 series advanced electronic resins. J Sep Sci 2002. [DOI: 10.1002/1615-9314(20020601)25:8<519::aid-jssc519>3.0.co;2-o] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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30
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Pietrogrande MC, Michi M, Plasencia MN, Dondi F. Analysis of PCB by on-line coupled HPLC-HRGC. Chromatographia 2002. [DOI: 10.1007/bf02492141] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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31
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Pietrogrand MC, Coll P, Sternberg R, Szopa C, Navarro-Gonzalez R, Vidal-Madjar C, Dondi F. Analysis of complex mixtures recovered from space missions statistical approach to the study of Titan atmosphere analogues (tholins). J Chromatogr A 2001; 939:69-77. [PMID: 11806547 DOI: 10.1016/s0021-9673(01)01333-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
To study Titan, the largest moon of Saturn, laboratory simulation experiments have been performed to obtain analogues of Titan's aerosols (named tholins) using different energy sources. Tholins, which have been demonstrated to represent aerosols in Titan's haze layers, are a complex mixture, resulting from the chemical evolution of several hydrocarbons and nitriles. Their chromatographic analysis yields complex chromatograms, which require the use of mathematical procedures to extract from them all the information they contain. Two different chemometric approaches (the Fourier analysis approach and the statistical model of peak overlapping) have been successfully applied to pyrolysis-GC-MS chromatogram of a tholin sample. Fundamental information on the mixture's chemical composition (number of components, m) and on the separation system performance (separation efficiency, sigma) can be easily estimated: the excellent correspondence between the data calculated by the two independent procedures proves the reliability of the statistical approaches in characterizing a tholin chromatogram. Moreover, the plot of autocorrelation function contains, in a simplified form, all the information on the retention pattern: retention recursivities can be easily singled out and related to specific molecular structure variations. Therefore, the autocorrelation function (ACF) plot constitutes a simplified fingerprint of the pyrolysis products of tholins, which can be used as a powerful tool to characterize a tholin sample.
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Huber CG, Timperio AM, Zolla L. Isoforms of photosystem II antenna proteins in different plant species revealed by liquid chromatography-electrospray ionization mass spectrometry. J Biol Chem 2001; 276:45755-61. [PMID: 11581262 DOI: 10.1074/jbc.m106700200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The high selectivity offered by reversed-phase high-performance liquid chromatography on-line coupled to electrospray ionization mass spectrometry has been utilized to characterize the major and minor light-harvesting proteins of photosystem II (Lhcb). Isomeric forms of the proteins, revealed either on the basis of different hydrophobicity enabling their chromatographic separation or on the basis of different molecular masses identified within one single chromatographic peak, were readily identified in a number of monocot and dicot species. The presence of several Lhcb1 isoforms (preferably in dicots) can explain the tendency of dicot Lhcb1 to form trimeric aggregates. The Lhcb1 molecular masses ranged from 24,680 to 25,014 among different species, whereas within the same species, the isoforms differed by 14-280 mass units. All Lhcb1 proteins appear to be highly conserved among different species such that they belong to a single gene group that has several different gene family members. In all species examined, the number of isoforms corresponded more or less to the genes cloned previously. Two isoforms of Lhcb3 were found in petunia and tomato. For Lhcb6, the most divergent of all light-harvesting proteins, the greatest number of isoforms was found in petunia, tobacco, tomato, and rice. Lhcb2, Lhcb4, and Lhcb5 were present in only one form. The isoforms are assumed to play an important role in the adaptation of plants to environmental changes.
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Affiliation(s)
- C G Huber
- Institute of Analytical Chemistry and Radiochemistry, Leopold-Franzens-University, Innrain 52a, 6020 Innsbruck, Austria.
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Marriot PJ, Shellie R, Cornwell C. Gas chromatographic technologies for the analysis of essential oils. J Chromatogr A 2001; 936:1-22. [PMID: 11760992 DOI: 10.1016/s0021-9673(01)01314-0] [Citation(s) in RCA: 195] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Essential oil analysis has basically had one technical goal: to achieve the best possible separation performance by using the most effective, available technology of the day. The result achieved from this may then be used to answer the research or industrial analysis questions which necessitated the analysis. This may be for comparative purposes, where one oil is contrasted with other(s) for quality control or investigation of adulteration, to discover new components, or to characterise the chemical classes of compounds present. Clearly, today the analyst turns to chromatography as the provider of separation and then may supplement that with mass spectrometry to aid identification. The power of GC-MS means that advances in both the separation technique, and improvements in mass spectrometry detection - along with improved data handling tools - will immediately be relevant to the essential oil area. This present review outlines the developmental nature of instrumental approaches to essential oil analysis using gas chromatography. Mass spectrometry will be included to the extent that it represents the hyphenation of choice for most analysts when analysing essential oils. Thus single-column and multi-dimensional analysis will be covered, as will sample handling or introduction techniques prior to the analysis step, where these techniques provide some measure of separation. The recent demonstration of comprehensive gas chromatography will be discussed as the potentially most powerful separation method for essential oils. This brief review is not intended to be a comprehensive dissertation on the field of essential oil analysis since that would require sufficient space to occupy a book in its own right. Rather, it will outline selected considerations and developments, to help explain where new technology has been applied to advantage in this field.
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Affiliation(s)
- P J Marriot
- Chromatography and Molecular Separations Group, Department of Applied Chemistry, GPO Box 2476V Melbourne 3001, RMIT University, Australia.
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Abstract
One of the weak points of capillary electrophoresis is the need to implement rigorously sample pretreatment because its great impact on the quality of the qualitative and quantitative results provided. One of the approaches to solve this problem is through the symbiosis of automatic continuous flow systems (CFSs) and capillary electrophoresis (CE). In this review a systematic approach to CFS-CE coupling is presented and discussed. The design of the corresponding interface depends on three factors, namely: (a) the characteristics of the CFS involved which can be non-chromatographic and chromatographic; (b) the type of CE equipment: laboratory-made or commercially available; and (c) the type of connection which can be in-line (on-capillary), on-line or mixed off/on-line. These are the basic criteria to qualify the hyphenation of CFS (solid-phase extraction, dialysis, gas diffusion, evaporation, direct leaching) with CE described so far and applied to determine a variety of analytes in many different types of samples. A critical discussion allows one to demonstrate that this symbiosis is an important topic in research and development, besides separation and detection, to consolidate CE as a routine analytical tool.
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Affiliation(s)
- M Valcárcel
- Analytical Chemistry Division, University of Córdoba, Spain.
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Grob K. Efficiency through combining high-performance liquid chromatography and high resolution gas chromatography: progress 1995-1999. J Chromatogr A 2000; 892:407-20. [PMID: 11045501 DOI: 10.1016/s0021-9673(00)00048-0] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Progress during the last 5 years in on-line LC-GC and related techniques is reviewed. In normal-phase LC-GC, the wire interface proved to have advantages over the loop type interface. Further investigations on the solvent evaporation process in an uncoated precolumn under conditions of an early vapour exit revealed that the rules for the transfer by the retention gap techniques must be modified. For reversed-phase LC-GC, approaches with a phase transfer compete with direct evaporation. Eluents were extracted into a bed of Tenax located in a programmed-temperature vaporiser and thermally desorbed. Direct evaporation is possible when a hot vaporising chamber is used and solvent/solute separation occurs in a separate compartment, a coated precolumn possibly in combination with packed beds. As a future strategy, LC-GC transfer techniques should be adjusted to those of large volume injection and involve a single device. It is believed that on-column injection/transfer is the choice. This requires that concurrent evaporation in LC-GC is performed by the on-column interface.
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Affiliation(s)
- K Grob
- Official Food Control Authority of the Canton of Zurich, Switzerland
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36
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Pasch H. Hyphenated Techniques in Liquid Chromatography of Polymers. ADVANCES IN POLYMER SCIENCE 2000. [DOI: 10.1007/3-540-48764-6_1] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
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37
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Holland LA, Jorgenson JW. Characterization of a comprehensive two-dimensional anion exchange-perfusive reversed phase liquid chromatography system for improved separations of peptides. ACTA ACUST UNITED AC 2000. [DOI: 10.1002/1520-667x(2000)12:6<371::aid-mcs6>3.0.co;2-n] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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38
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Blanch GP, Ruiz del Castillo ML, Herraiz M. Evaluation of a transfer technique for direct coupling of reversed-phase liquid chromatography with gas chromatography. J Chromatogr A 1998. [DOI: 10.1016/s0021-9673(98)00526-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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39
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Protein Analysis. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0301-4770(08)60311-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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40
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Baner AL, Guggenberger A. Analysis of tinuvin 1577 polymer additive in edible oils using on-line coupled HPLC-GC. ACTA ACUST UNITED AC 1997. [DOI: 10.1002/jhrc.1240201210] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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41
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Novotny MV. Capillary biomolecular separations. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1997; 689:55-70. [PMID: 9061482 DOI: 10.1016/s0378-4347(96)00398-2] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
This article summarizes the recent advances in microcolumn separations of biopolymers. Microcolumn liquid chromatography is primarily emphasized for its role as a micropreparative and fractionation tool, whereas high-performance capillary electrophoresis is demonstrated as a highly efficient technique for final analyses. Following a brief discussion of new trends in instrumentation, the recent applications of capillary techniques to proteins, DNA and glycoconjugates are reviewed.
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Affiliation(s)
- M V Novotny
- Department of Chemistry, Indiana University, Bloomington 47405, USA
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42
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Liu YM, Sweedler JV. Two-dimensional separations: capillary electrophoresis coupled to channel gel electrophoresis. Anal Chem 1996; 68:3928-33. [PMID: 8916451 DOI: 10.1021/ac960549+] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Two-dimensional separations provide extremely high peak capacities. Coupling capillary zone electrophoresis with ultrathin channel gel electrophoresis offers a convenient and efficient way to perform such two-dimensional microseparations. By means of in situ polymerization, high-concentration (up to 50%T) polyacrylamide gels are prepared in 75 mm long, 25 mm wide, and 40 microns thick rectangular channels. By moving the outlet end of the capillary electrophoresis capillary across the entrance of the channel, both separations are completely preserved. Mixtures of peptides labeled by fluorescein isothiocyanate (FITC) are well resolved in less than 15 min, with theoretical plate numbers in the range of 20,000-50,000 for each independent separation. Significant enhancement in separation efficiency and peak capacity over one-dimensional separations are demonstrated by this combination. The two-dimensional separations of a model mixture of peptides, a tryptic digest of trypsinogen, and < 0.05% of an individual B2 neuron from the marine mollusk Aplysia californica are presented.
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Affiliation(s)
- Y M Liu
- Department of Chemistry, University of Illinois at Urbana-Champaign 61801, USA
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Leira E, Botana A, Cela R. Resolution of complex mixtures of non-flavonoid polyphenols by column-switching high-performance liquid chromatography using octadecylsilica and graphitized carbon columns. J Chromatogr A 1996. [DOI: 10.1016/0021-9673(95)00852-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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45
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Affiliation(s)
- M V Novotny
- Department of Chemistry, Indiana University, Bloomington 47405, USA
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46
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Mondello L, Dugo G, Bartle KD. On-line microbore high performance liquid chromatography-capillary gas chromatography for food and water analyses. A review. ACTA ACUST UNITED AC 1996. [DOI: 10.1002/(sici)1520-667x(1996)8:4<275::aid-mcs5>3.0.co;2-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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47
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Tomlinson MJ, Sasaki TA, Wilkins CL. Applications of multidimensional-gas chromatography-mass spectrometry and gas chromatography-Fourier transform infrared-mass spectrometry. MASS SPECTROMETRY REVIEWS 1996; 15:1-14. [PMID: 27082167 DOI: 10.1002/(sici)1098-2787(1996)15:1<1::aid-mas1>3.0.co;2-m] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/1996] [Revised: 09/11/1996] [Accepted: 09/12/1996] [Indexed: 06/05/2023]
Abstract
Gas chromatography systems with coupled columns in a multidimensional (MD) mode have become more important for the analysis of complex mixtures, due to the increased selectivity that can be achieved by the use of multiple columns with differing stationary phases. Coupling two or more detectors can also help to increase the information content of the analysis. This review presents the various strategies used in multidimensional gas chromatography (MDGC), with Fourier transform infrared (FT-IR) and/or mass spectrometric (MS) detection, with an emphasis on applications of these techniques for analysis of components in complex matrices. © 1997 John Wiley & Sons, Inc.
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Affiliation(s)
- M J Tomlinson
- University of California-Riverside, Department of Chemistry, Riverside, California 92521-0403
| | - T A Sasaki
- University of California-Riverside, Department of Chemistry, Riverside, California 92521-0403
| | - C L Wilkins
- University of California-Riverside, Department of Chemistry, Riverside, California 92521-0403
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Grob K, Bronz M. On-line LC-GC transfer via a hot vaporizing chamber and vapor discharge by overflow; increased sensitivity for the determination of mineral oil in foods. ACTA ACUST UNITED AC 1995. [DOI: 10.1002/mcs.1220070415] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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49
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Grob K. Development of the transfer techniques for on-line high-performance liquid chromatography-capillary gas chromatography. J Chromatogr A 1995. [DOI: 10.1016/0021-9673(95)00094-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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50
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Sandra P, Kot A, Medvedovici A, David F. Selected applications of the use of supercritical fluids in coupled systems. J Chromatogr A 1995. [DOI: 10.1016/0021-9673(95)00050-w] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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