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Nazim T, Lusina A, Cegłowski M. Recent Developments in the Detection of Organic Contaminants Using Molecularly Imprinted Polymers Combined with Various Analytical Techniques. Polymers (Basel) 2023; 15:3868. [PMID: 37835917 PMCID: PMC10574876 DOI: 10.3390/polym15193868] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 09/13/2023] [Accepted: 09/21/2023] [Indexed: 10/15/2023] Open
Abstract
Molecularly imprinted polymers (MIPs) encompass a diverse array of polymeric matrices that exhibit the unique capacity to selectively identify a designated template molecule through specific chemical moieties. Thanks to their pivotal attributes, including exceptional selectivity, extended shelf stability, and other distinct characteristics, this class of compounds has garnered interest in the development of highly responsive sensor systems. As a result, the incorporation of MIPs in crafting distinctive sensors and analytical procedures tailored for specific analytes across various domains has increasingly become a common practice within contemporary analytical chemistry. Furthermore, the range of polymers amenable to MIP formulation significantly influences the potential utilization of both conventional and innovative analytical methodologies. This versatility expands the array of possibilities in which MIP-based sensing can be employed in recognition systems. The following review summarizes the notable progress achieved within the preceding seven-year period in employing MIP-based sensing techniques for analyte determination.
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Affiliation(s)
| | | | - Michał Cegłowski
- Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland; (T.N.); (A.L.)
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2
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Kaushik Rangadurai A, Toyama Y, Kay LE. Practical considerations for the measurement of near-surface electrostatics based on solvent paramagnetic relaxation enhancements. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2023; 349:107400. [PMID: 36796143 DOI: 10.1016/j.jmr.2023.107400] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/02/2023] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
Electrostatic interactions can play important roles in regulating various biological processes. Quantifying surface electrostatics of biomolecules is, therefore, of significant interest. Recent advances in solution NMR spectroscopy have enabled site-specific measurements of de novo near-surface electrostatic potentials (ϕENS) based on a comparison of solvent paramagnetic relaxation enhancements generated from differently charged paramagnetic co-solutes with similar structures. Although the NMR-derived near-surface electrostatic potentials have been shown to agree with theoretical calculations in the context of folded proteins and nucleic acids, such benchmark comparisons may not always be possible, particularly in cases where high-resolution structural models are lacking, such as in the study of intrinsically disordered proteins. Cross-validation of ϕENS potentials can be achieved by comparing values obtained using three pairs of paramagnetic co-solutes, each with a different net charge. Notably we have found cases where agreement of ϕENS potentials between the three pairs is poor and herein we investigate the source of this discrepancy in some detail. We show that for the systems considered here ϕENS potentials obtained from cationic and anionic co-solutes are accurate and that the use of paramagnetic co-solutes with different structures can be a viable option for validation, although the optimal choice of paramagnetic compounds depends on the system of interest.
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Affiliation(s)
- Atul Kaushik Rangadurai
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Department of Chemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Hospital for Sick Children, Program in Molecular Medicine, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
| | - Yuki Toyama
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Department of Chemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
| | - Lewis E Kay
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Department of Chemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada; Hospital for Sick Children, Program in Molecular Medicine, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
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3
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Scheidt T, Kartanas T, Peter Q, Schneider MM, Saar KL, Müller T, Challa PK, Levin A, Devenish S, Knowles TPJ. Multidimensional protein characterisation using microfluidic post-column analysis. LAB ON A CHIP 2020; 20:2663-2673. [PMID: 32588855 DOI: 10.1039/d0lc00219d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The biological function of proteins is dictated by the formation of supra-molecular complexes that act as the basic machinery of the cell. As such, measuring the properties of protein species in heterogeneous mixtures is of key importance for understanding the molecular basis of biological function. Here, we describe the combination of analytical microfluidic tools with liquid chromatography for multidimensional characterisation of biomolecules in complex mixtures in the solution phase. Following chromatographic separation, a small fraction of the flow-through is distributed to multiple microfluidic devices for analysis. The microfluidic device developed here allows the simultaneous determination of the hydrodynamic radius, electrophoretic mobility, effective molecular charge and isoelectric point of isolated protein species. We demonstrate the operation principle of this approach with a mixture of three unlabelled model proteins varying in size and charge. We further extend the analytical potential of the presented approach by analysing a mixture of interacting streptavidin with biotinylated BSA and fluorophores, which form a mixture of stable complexes with diverse biophysical properties and stoichiometries. The presented microfluidic device positioned in-line with liquid chromatography presents an advanced tool for characterising multidimensional physical properties of proteins in biological samples to further understand the assembly/disassembly mechanism of proteins and the nature of complex mixtures.
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Affiliation(s)
- Tom Scheidt
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, UK.
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Benítez-Mateos AI, Nidetzky B, Bolivar JM, López-Gallego F. Single-Particle Studies to Advance the Characterization of Heterogeneous Biocatalysts. ChemCatChem 2018. [DOI: 10.1002/cctc.201701590] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Ana I. Benítez-Mateos
- Heterogeneous Biocatalysis Group; CIC BiomaGUNE; Paseo Miramon 182 San Sebastian-Donostia 20014 Spain
| | - Bernd Nidetzky
- Institute of Biotechnology and Biochemical Engineering; Graz University of Technology, NAWI Graz; Petersgasse 12 8010 Graz Austria
- Austrian Centre of Industrial Biotechnology; Petersgasse 14 8010 Graz Austria
| | - Juan M. Bolivar
- Institute of Biotechnology and Biochemical Engineering; Graz University of Technology, NAWI Graz; Petersgasse 12 8010 Graz Austria
| | - Fernando López-Gallego
- Heterogeneous Biocatalysis Group; CIC BiomaGUNE; Paseo Miramon 182 San Sebastian-Donostia 20014 Spain
- IKERBASQUE; Basque Foundation for Science; Bilbao Spain
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6
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Enantio sensing property of helicin, the derivative of a natural product: Discrimination of amines and amino alcohols. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.07.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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7
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Xie L, Jiang R, Zhu F, Liu H, Ouyang G. Application of functionalized magnetic nanoparticles in sample preparation. Anal Bioanal Chem 2013; 406:377-99. [PMID: 24037613 DOI: 10.1007/s00216-013-7302-6] [Citation(s) in RCA: 209] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2013] [Revised: 08/11/2013] [Accepted: 08/13/2013] [Indexed: 11/26/2022]
Abstract
Functionalized magnetic nanoparticles have attracted much attention in sample preparation because of their excellent performance compared with traditional sample-preparation sorbents. In this review, we describe the application of magnetic nanoparticles functionalized with silica, octadecylsilane, carbon-based material, surfactants, and polymers as adsorbents for separation and preconcentration of analytes from a variety of matrices. Magnetic solid-phase extraction (MSPE) techniques, mainly reported in the last five years, are presented and discussed.
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Affiliation(s)
- Lijun Xie
- MOE Key Laboratory of Aquatic Product Safety/KLGHEI of Environment and Energy Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou, 510275, China
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Hao W, Di B, Chen Q, Wang J, Yang Y, Sun X. Study of the peak variance in isocratic and gradient liquid chromatography using the transport model. J Chromatogr A 2013; 1295:67-81. [DOI: 10.1016/j.chroma.2013.04.044] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 04/08/2013] [Accepted: 04/15/2013] [Indexed: 10/26/2022]
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9
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Determination of Pyrethroid Pesticides in Environmental Waters Based on Magnetic Titanium Dioxide Nanoparticles Extraction Followed by HPLC Analysis. Chromatographia 2013. [DOI: 10.1007/s10337-013-2393-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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10
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Application of derivatized magnetic materials to the separation and the preconcentration of pollutants in water samples. Trends Analyt Chem 2011. [DOI: 10.1016/j.trac.2011.02.013] [Citation(s) in RCA: 209] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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11
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Naziroglu HN, Durmaz M, Bozkurt S, Sirit A. Application of L-proline derivatives as chiral shift reagents for enantiomeric recognition of carboxylic acids. Chirality 2011; 23:463-71. [DOI: 10.1002/chir.20948] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2010] [Accepted: 12/23/2010] [Indexed: 11/10/2022]
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12
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Bozkurt S, Durmaz M, Naziroglu HN, Yilmaz M, Sirit A. Amino alcohol based chiral solvating agents: synthesis and applications in the NMR enantiodiscrimination of carboxylic acids. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/j.tetasy.2011.02.028] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Bocian S, Buszewski B. Retention mechanism of the multifunctional solute on columns with different coverage densities using highly aqueous reversed-phase conditions. J Sep Sci 2010; 33:3033-42. [DOI: 10.1002/jssc.201000278] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Iuliani P, Carlucci G, Marrone A. Investigation of the HPLC response of NSAIDs by fractional experimental design and multivariate regression analysis. Response optimization and new retention parameters. J Pharm Biomed Anal 2010; 51:46-55. [DOI: 10.1016/j.jpba.2009.08.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2009] [Revised: 07/29/2009] [Accepted: 08/03/2009] [Indexed: 10/20/2022]
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16
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Mori S, Balke ST. ISPAC and Dr. Howard G. Barth. INTERNATIONAL JOURNAL OF POLYMER ANALYSIS AND CHARACTERIZATION 2008. [DOI: 10.1080/10236660701824274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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17
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On-column electrochemical redox derivatization for enhancement of separation selectivity of liquid chromatography. J Chromatogr A 2008; 1180:66-72. [DOI: 10.1016/j.chroma.2007.12.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2007] [Revised: 11/22/2007] [Accepted: 12/03/2007] [Indexed: 11/22/2022]
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18
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Kadar EP, Wujcik CE, Wolford DP, Kavetskaia O. Rapid determination of the applicability of hydrophilic interaction chromatography utilizing ACD Labs Log D Suite: A bioanalytical application. J Chromatogr B Analyt Technol Biomed Life Sci 2008; 863:1-8. [DOI: 10.1016/j.jchromb.2007.11.036] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Revised: 11/16/2007] [Accepted: 11/26/2007] [Indexed: 11/28/2022]
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19
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Bereznitski Y, Jaroniec M. LIQUID CHROMATOGRAPHY STUDIES OF ACETONITRILE SORPTION ON SILICA-BASED OCTYL PHASES. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-100101777] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Yuri Bereznitski
- a Separation and Surface Science Center, Chemistry Department , Kent State University , Kent , OH , 44242 , U.S.A
| | - Mietek Jaroniec
- b Separation and Surface Science Center, Chemistry Department , Kent State University , Kent , OH , 44242 , U.S.A
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Affiliation(s)
- Yu Xin
- a Center for Molecular Science, Institute of Chemistry, The Chinese Academy of Science , Beijing, 100080, P. R. China
| | - Zhao Rui
- a Center for Molecular Science, Institute of Chemistry, The Chinese Academy of Science , Beijing, 100080, P. R. China
| | - Liu Guoquan
- b Center for Molecular Science, Institute of Chemistry, The Chinese Academy of Science , Beijing, 100080, P. R. China
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21
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Hao W, Zhang X, Hou K. Analytical Solutions of the Ideal Model for Gradient Liquid Chromatography. Anal Chem 2006; 78:7828-40. [PMID: 17105177 DOI: 10.1021/ac061318y] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The analytical solutions of the ideal model for gradient elution that ignores the influence of the solute concentration on the retention factor (k) were studied by using the method of characteristics for solving partial differential equations. It is found for any gradient profiles and solvent strength models used that the concentration of the solute will be discontinuous where the mobile-phase composition is. On a given characteristic curve, the product of the concentration and the retention factor is kept constant at the point where the concentration is continuous. At the point where the concentration is discontinuous, the product on the left side of this point is equal to that on the right side. We also discussed the basic equations to predict the retention time in gradient elution and introduced the injection time into them. For linear solvent strength stepwise and linear gradient elution, general expressions were proposed for the prediction and they can be used as the basis to derive others for specific gradient modes such as single linear, stepwise, and ladderlike gradients. For these modes, simple expressions to account for the band compression and the concentration change during the elution were also given.
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Affiliation(s)
- Weiqiang Hao
- Department of Chemistry, Fudan University, Shanghai 200433, China, and Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
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22
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Bazylak G, Aboul-Enein HY. Chemometric Account for Retention of Lysosomotropic Alkanolamines in Planar Chromatography Systems. J LIQ CHROMATOGR R T 2006. [DOI: 10.1080/10826079708002706] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- G. Bazylak
- a Biochromatographic Laboratory Hygienics, Department Medical University of Lódz , Jaracza 63 PL-90-251, Lódz, Poland
| | - H. Y. Aboul-Enein
- b Bioanalytical and Drug Development Laboratory Biological & Medical Research Department , MBC-03 King Faisal Specialist Hospital & Research Centre , P.O.Box 3354, Riyadh, 11211, Saudi Arabia
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23
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Jandera P, Novotná K, Beldean-Galea MS, Jísa K. Retention and selectivity tests of silica-based and metal-oxide bonded stationary phases for RP-HPLC. J Sep Sci 2006; 29:856-71. [PMID: 16830498 DOI: 10.1002/jssc.200500489] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Chromatographic properties of silica-, zirconia- and alumina-based columns with octadecyl-, polyethylene glycol- and pentafluorophenylpropyl-bonded stationary phases were tested. Selectivities of nine columns for LC were characterized using chromatographic methods including Walters, Engelhardt, Tanaka and Galushko hydrophobicity and silanol activity tests, measurements of methylene selectivity in various aqueous-methanol and aqueous-acetonitrile mobile phases and of gradient lipophilic capacity as a measure of the effect of the sample hydrophobicity on gradient-elution separations. A semi-empirical interaction indices model, assuming a predominant role of the solvophobic interactions of test compounds with different polarities, was compared with the linear free energy relationships approach taking into account selective polar interactions. The interaction indices model was applied to both non-polar stationary phases bonded on silica, alumina and zirconia supports, and to the non-modified adsorbents in the normal-phase LC. The retention data of isomeric naphthalene disulfonic acids were used to compare the attractive and repulsive ionic interactions of the columns in purely aqueous mobile phases. The results of the hydrophobicity and polarity tests were consistent, and allowed column characterization and classification. Silanol activity was important with octadecyl silica columns, but was relatively insignificant with bonded polyethylene glycol and pentafluorophenylpropyl phases on silica gel support. Polar interactions with the alumina and zirconia support materials significantly affect the retention.
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Affiliation(s)
- Pavel Jandera
- Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Pardubice, Czech Republic.
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24
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Soukupová K, Krafková E, Suchánková J, Tesarová E. Comparison of zirconia- and silica-based reversed stationary phases for separation of enkephalins. J Chromatogr A 2005; 1087:104-11. [PMID: 16130703 DOI: 10.1016/j.chroma.2005.01.058] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In this study, the separation of biologically active peptides on two zirconia-based phases, polybutadiene (PBD)-ZrO2 and polystyrene (PS)-ZrO2, and a silica-based phase C18 was compared. Basic differences in interactions on both types of phases led to quite different selectivity. The retention characteristics were investigated in detail using a variety of organic modifiers, buffers, and temperatures. These parameters affected retention, separation efficiency, resolution and symmetry of peaks. Separation systems consisting of Discovery PBD-Zr column and mobile phase composed of a mixture of acetonitrile and phosphate buffer, pH 2.0 (45:55, v/v) at 70 degrees C and Discovery PS-Zr with acetonitrile and phosphate buffer, pH 3.5 in the same (v/v) ratio at 40 degrees C were suitable for a good resolution of enkephalin related peptides. Mobile phase composed of acetonitrile and phosphate buffer, pH 5.0 (22:78, v/v) was appropriate for separation of enkephalins on Supelcosil C18 stationary phase.
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Affiliation(s)
- K Soukupová
- Department of Analytical Chemistry, Faculty of Science, Charles University, Albertov 2030, 12840 Prague 2, Czech Republic
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Rimmer CA, Sander LC, Wise SA, Dorsey JG. Synthesis and characterization of C13 to C18 stationary phases by monomeric, solution polymerized, and surface polymerized approaches. J Chromatogr A 2003; 1007:11-20. [PMID: 12924546 DOI: 10.1016/s0021-9673(03)00959-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A series of bonded phases were synthesized from consecutive length alkylsilanes ranging from C13 through C18, with three different bonding chemistries (monomeric, solution polymerized, and surface polymerized) at each phase length. The phases were characterized in terms of methylene selectivity, shape selectivity, and band broadening. No significant chromatographic differences were found to result from the synthetic routes, except that the different bonding chemistries provide a different range of bonding densities. For bonding densities ranging from 2 to 8 micromol/m2, a linear increase in methylene selectivity was observed with increasing bonding density. Over the narrow range of bonded phase lengths investigated, shape selectivity is more dependent on density than phase length.
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Affiliation(s)
- Catherine A Rimmer
- Chemical Science and Technology Laboratory, Analytical Chemistry Division, National Institute of Standards and Technology, 100 Bureau Drive. Stop 8392, Gaithersburg, MD 20899-8392, USA.
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Dai J, Yang X, Carr PW. Comparison of the chromatography of octadecyl silane bonded silica and polybutadiene-coated zirconia phases based on a diverse set of cationic drugs. J Chromatogr A 2003; 1005:63-82. [PMID: 12924783 DOI: 10.1016/s0021-9673(03)00929-4] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this study, we compare the separation of basic drugs on several octadecyl silane bonded silica (ODS) phases and a polybutadiene-coated zirconia (PBD-ZrO2) phase. The retention characteristics were investigated in detail using a variety of cationic drugs as probe solutes. The ODS phases were selected to cover a relatively wide range in silanol activity and were studied with ammonium phosphate eluents at pH 3.0 and 6.0. Compared to any of the ODS phases, the PBD-ZrO2 phase showed very significant differences in selectivities towards these drugs. Due to the presence of both reversed-phase and ion-exchange interactions between the stationary phase and the basic analyte on ODS and PBD-ZrO2, mixed-mode retention takes place to some extent on both types of phases. However, very large differences in the relative contributions from ion-exchange and reversed-phase interactions on the two types of phases led to quite different selectivities. When phosphate is present in the eluent and adsorbs on the surface, the PBD-ZrO2 phase takes on a high negative charge over a wide pH range due to phosphate adsorption on its surface. On ODS phases, ion-exchange interactions result from the interactions between protonated basic compounds and ionized residual silanol groups. Since the pH of the eluent influences the charge state of the silanol groups, the ion-exchange interactions vary in strength depending on pH. At pH 6.0, the ion-exchange interactions are strong. However, at pH 3.0 the ion-exchange interactions on ODS are significantly smaller because the silanol groups are less dissociated at the lower pH. Thus, not only are the selectivities of the ODS and PBD-ZrO2 phases different but quite different trends in retention are observed on these two types of phases as the pH of the eluent is varied. More importantly, by using the large set of "real" basic analytes we show the extreme complexity of the chromatographic processes on the reversed stationary phases. Both the test condition and solute property influence the column performance. Therefore, use of only one or two probe solutes is not sufficient for column ranking.
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Affiliation(s)
- Jun Dai
- Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, MN 55455-0431, USA
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Resolution of N-acyl-1-naphthylalkylamide on amide and sulfonamide-derived π-acidic chiral stationary phases. Microchem J 2003. [DOI: 10.1016/s0026-265x(03)00030-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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28
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Shibukawa M, Unno A, Miura T, Nagoya A, Oguma K. On-column derivatization using redox activity of porous graphitic carbon stationary phase: an approach to enhancement of separation selectivity of liquid chromatography. Anal Chem 2003; 75:2775-83. [PMID: 12948149 DOI: 10.1021/ac020705e] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A new on-column derivatization method based on the redox activity of porous graphitic carbon (PGC) packing materials was presented for enhancement of separation selectivity of HPLC. Two PGC packing materials were used as the solid redox agents as well as the stationary phase, and their redox activities were investigated using trans-1,2-diaminocyclohexanetetraacetate (DCTA) complexes of some metal ions as probe compounds. It was found that the redox property of PGC was modified by treating them with a solution containing a reducing agent, sodium sulfite or hydroxylammonium chloride. The original PGC packings oxidized Co(II)-DCTA to Co(III)-DCTA during elution, while the PGC treated with a reducing agent showed reduction activity converting Co(III)-DCTA to Co(II)-DCTA. These two cobalt complexes do not form their individual chromatographic zones but migrate as a single zone of their mixture on the PGC column contrary to the chromatographic behavior on a C18 bonded silica, on which Co(II)-DCTA and Co(III)-DCTA can be separated. Treatment of the PGC column with a reducing agent solution transforms the oxidative activity of the original PGC packing to a reductive one from the upper part of the column, so that the retention time of the cobalt complex can be controlled by changing the volume of the reducing agent solution to be used for treatment of the PGC column. The selective separation and determination of cobalt in a reference manganese nodule sample by the developed method was demonstrated.
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Affiliation(s)
- Masami Shibukawa
- Department of Applied Molecular Chemistry, College of Industrial Technology, Nihon University, 1-2-1, Izumi-cho, Narashino, 275-8575, Japan.
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Im SH, Ryoo JJ, Lee KP, Choi SH, Jeong YH, Jung YS, Hyun MH. NMR studies of chiral discrimination relevant to the enantioseparation of N-acylarylalkylamines by an (R)-phenylglycinol-derived chiral selector. Chirality 2002; 14:329-33. [PMID: 11968074 DOI: 10.1002/chir.10071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Recently, it was reported that the chiral recognition ability of (R)-N-3,5-dinitrobenzoyl phenylglycinol derivative was examined as a new HPLC chiral stationary phase (CSP 1) for the resolution of racemic N-acylnaphthylalkylamines. However, the mechanism of chiral discrimination on the CSP remained elusive until now. In this study, a spectroscopic investigation of the chiral discrimination mechanism of CSP 1 was undertaken using mixtures of (R)-N-3,5-dinitrobenzoyl phenylglycinol-derived chiral selector (2) and each of the enantiomers of N-acylnaphthylalkylamines (3) by NMR study. First, the differences in free energy changes (DeltaDeltaG) upon diastereomeric complexation in solution between the complex of each isomer with chiral selector 2 by NMR titration were calculated. The values were then compared with those estimated by chiral HPLC. The chemical shift changes of each proton on the chiral selector and analytes were also checked and it was found that the chemical shift changes decreased continuously as the acyl group on analytes increased in length. This observation was consistent with the HPLC data. From these experimental results, the interaction mechanism of chiral discrimination between the chiral selector and the analytes is more precisely explained.
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Affiliation(s)
- Sung Hyun Im
- Analytical Laboratory, R&D Institute, LG Household & Health Care, Taejon, Korea
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30
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Zarzycki PK, Kulhanek KM, Smith R. Chromatographic behaviour of selected steroids and their inclusion complexes with beta-cyclodextrin on octadecylsilica stationary phases with different carbon loads. J Chromatogr A 2002; 955:71-8. [PMID: 12061564 DOI: 10.1016/s0021-9673(02)00196-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Retention and separation studies of selected estrogens, progestogens and their inclusion complexes with beta-cyclodextrin were conducted using two C18 HPLC columns with different carbon loads. The difference in carbon load between investigated octadecylsilica packing materials was about 50%. The mobile phases were composed of a 30% v/v acetonitrile-water mixture without and with addition of beta-cyclodextrin at a concentration of 12 mM. The experimental data revealed that retention of the steroids was significantly reduced on the column with the lower carbon load. Moreover, it was found that this column offers better separation power and shorter analysis time at the temperatures studied. However, the calculated values of the retention factor ratios (k0(mMCD))/k(12mMCD)) of the steroids were similar for both columns investigated. This observation suggests that the stationary phase structure appears to have little effect on the formation of host-guest complexes if the complexation process is localised to the chromatographic mobile phase. From a practical point of view, when the mobile phase is modified with beta-cyclodextrin, the separation of the steroids is strongly influenced by temperature. The best chromatographic conditions were determined for the separation of multicomponent samples on the column with lower carbon load. A possible retention mechanism for components of interest in the presence of macrocyclic additives is discussed.
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Affiliation(s)
- Pawel K Zarzycki
- Mothers and Babies Research Center, The University of Newcastle and the John Hunter Hospital, Newcastle, NSW, Australia.
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31
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Abstract
Chiral drugs, agrochemicals, food additives and fragrances represent classes of compounds with high economic and scientific potential. First the present implications of their chiral nature and necessity of separating enantiomers are summarised in this article. In the following a brief overview of the actual approaches to perform enantioseparations at analytical and preparative scale is given. Challenging aspects of these strategies, such as problems associated with data management, choice of suitable chiral selectors for given enantioseparations and enhanced understanding of the underlying chiral recognition principles, are discussed. Alternatives capable of meeting the requirements of industrial processes, in terms of productivity, cost-effectiveness and environmental issues (e.g., enantioselective membranes) are critically reviewed. The impact of combinatorial methodologies on faster and more effective development and optimisation of novel chiral selectors is outlined. Finally, the merits and limitations of most recent trends in discrimination of enantiomers, including advances in the fields of sensors, microanalysis systems, chiroptical methods and chemical force microscopy are evaluated.
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Affiliation(s)
- N M Maier
- Institute of Analytical Chemistry, University of Vienna, Austria
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32
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Švec F, Petro M, Fréchet JMJ. Separation of Hydrophilic Oligomers and Polymers Using Monodisperse Poly(2,3-dihydroxypropyl Methacrylate-co-Ethylene Dimethacrylate) Beads via Normal-Phase and Hydrophilic-Interaction HPLC. ACTA ACUST UNITED AC 2001. [DOI: 10.1135/cccc20011047] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Microparticulate, monosized, and macroporous poly(2,3-dihydroxypropyl methacrylate-co-ethylene dimethacrylate) beads have been used as a stationary phase for HPLC separations of hydrophilic oligomers and polymers. Homogeneous coverage of the sorbent surface with a large number of chemically equivalent diol functionalities affords suitable retentivity in both normal-phase and hydrophilic-interaction chromatographic modes and enables the separations of water-soluble oligomers and polymers. Chromatographic properties of this stationary phase are demonstrated on a variety of separations of poly(oxyalkylene)s, polyvinylpyrrolidones, and polysaccharides.
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33
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Nishino I, Fujitomo H, Umeda T. Determination of a new oral cephalosporin, cefmatilen hydrochloride hydrate, and its seven metabolites in human and animal plasma and urine by coupled systems of ion-exchange and reversed-phase high-performance liquid chromatography. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2000; 749:101-10. [PMID: 11129069 DOI: 10.1016/s0378-4347(00)00381-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Multidimensional HPLC systems with coupled anion-exchange, cation-exchange, and reversed-phase columns, and ultraviolet and electrochemical detectors were developed for the determination of cefmatilen and its seven metabolites in the plasma and urine of humans and animals. These target compounds with a wide range of polarities were efficiently separated and determined by HPLC assay methods with simple pretreatments, deproteinization of plasma and dilution of urine. The assay methods showed good linearity, precision and accuracy. The methods were successfully applied to pharmacokinetic and metabolic studies of cefmatilen hydrochloride hydrate administered orally to humans and animals.
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Affiliation(s)
- I Nishino
- Shionogi Research Laboratories, Shionogi & Co., Ltd., Osaka, Japan
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34
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35
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Yamagami C, Araki K, Ohnishi K, Hanasato K, Inaba H, Aono M, Ohta A. Measurement and prediction of hydrophobicity parameters for highly lipophilic compounds: application of the HPLC column-switching technique to measurement of log P of diarylpyrazines. J Pharm Sci 1999; 88:1299-304. [PMID: 10585226 DOI: 10.1021/js990112s] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the preparatory stage of structure-activity relationship (QSAR) studies of anti-platelet aggregant pyrazine derivatives, log P values (P: 1-octanol/water partition coefficient) of diarylpyrazines were measured by a newly developed HPLC column-switching technique. The system consists of two processes: (1) adsorption of the sample at the top end of a short precolumn, and then (2) quantifying the enriched analyte by a conventional analytical column. By using the log P values thus obtained, the correction factor for the steric hindrance caused by the vicinal diphenyl groups was estimated. The log k values (k; retention factor) were also measured with methanol-buffer (pH 7.4) eluents and related to log P. The eluent of 50% methanol content (M50) gave a good linear relationship over a wide range of log P (-0.3< log P < 5.2), indicating that log k(M50) parameter is useful for predicting the log P value.
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Affiliation(s)
- C Yamagami
- Kobe Pharmaceutical University, Motoyamakita-machi, Higashinada, Kobe, 658-8558, Japan.
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36
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Szabó PT, Kele Z, Birkó Z, Szeszák F, Bíró S, Janáky T. Identification of factor C protein from Streptomyces griseus by microelectrospray mass spectrometry. JOURNAL OF MASS SPECTROMETRY : JMS 1999; 34:1312-1316. [PMID: 10587626 DOI: 10.1002/(sici)1096-9888(199912)34:12<1312::aid-jms885>3.0.co;2-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Factor C, an extracellular signal protein of cellular differentiation, was studied and significant homology was found to several zinc finger-type regulatory proteins. The complete amino acid sequence, deduced from the gene, that encodes the protein, did not support the hypothesis that this protein might be a zinc finger-type regulatory protein. However, a theoretical single nucleotide insertion in the gene can result in another similarly sized protein containing about 20 His residues, which would be responsible for the high zinc affinity of factor C. The protein sample was reduced, alkylated and then in-gel digested with trypsin. The peptide fragments were then separated by capillary chromatography and identified by microelectrospray mass spectrometry. Peaks of higher intensity were sequenced by tandem mass spectrometry. The identified peptide fragments and the measured molecular mass of factor C protein also confirmed the original sequence of protein, as there was no shift in the open reading frame.
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Affiliation(s)
- P T Szabó
- Department of Medical Chemistry, Albert Szent-Györgyi Medical University, Dóm tér 8, H-6720 Szeged, Hungary.
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37
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Kele M, Guiochon G. Repeatability and reproducibility of retention data and band profiles on reversed-phase liquid chromatography columns. III. Results obtained with Kromasil C18 columns. J Chromatogr A 1999; 855:423-53. [PMID: 10519085 DOI: 10.1016/s0021-9673(99)00746-3] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The reproducibility of the retention data and the band profiles was investigated with Kromasil C18 columns (silica-based monomeric type reversed-phase packing material). High precision data were obtained and statistically compared among five columns from the same batch (column-to-column reproducibility) and six columns, one from each of six different batches (batch-to-batch reproducibility). These data were acquired under five different sets of chromatographic conditions, for a group of 30 neutral, acidic and basic compounds selected as probes following an experimental protocol previously described. Data characterizing the retention time, the retention factor, the separation factor, the column efficiency and the peak asymmetry for the different probe compounds are reported. Factors describing the silica surface interaction with the selected probe compounds, such as the hydrophobic interaction selectivity, the steric selectivity, and the separation factors of basic compounds at different pH values were also determined. The influence of the underlying silica on these data and correlations between the chromatographic and physico-chemical properties of the different batches are discussed.
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Affiliation(s)
- M Kele
- Department of Chemistry, University of Tennessee, Knoxville 37996-1600, USA
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38
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Resolution of Racemic N-Acyl-1-arylaminoalkanes on a (3,5-Dinitrobenzoyl)phenylglycinol-Derived High Performance Liquid Chromatography Chiral Stationary Phase. Microchem J 1999. [DOI: 10.1006/mchj.1999.1774] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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39
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Measurement of enantiomeric purity by ratio chromatograms with a photometric detector using quartz plates as a multiple retarder. Anal Chim Acta 1999. [DOI: 10.1016/s0003-2670(99)00446-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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40
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Bereznitski Y, Jaroniec M, Gangoda M. Characterization of silica-based octyl phases of different bonding density. J Chromatogr A 1998. [DOI: 10.1016/s0021-9673(98)00830-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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41
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Enantiomeric separations of benzodiazepines by electrochemically modulated liquid chromatography. J Chromatogr A 1998. [DOI: 10.1016/s0021-9673(98)00701-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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42
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Ho M, Wang S, Porter MD. Electrosorption-Based Modification of Porous Graphitic Carbon: Use of Electrochemically Modulated Liquid Chromatography To Create a Chiral Stationary Phase for Enantiomeric Separations. Anal Chem 1998. [DOI: 10.1021/ac980431o] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mankit Ho
- Department of Chemistry, Ames LaboratoryUSDOE, and Microanalytical Instrumentation Center, Iowa State University, Ames, Iowa 50011
| | - Songjie Wang
- Department of Chemistry, Ames LaboratoryUSDOE, and Microanalytical Instrumentation Center, Iowa State University, Ames, Iowa 50011
| | - Marc D. Porter
- Department of Chemistry, Ames LaboratoryUSDOE, and Microanalytical Instrumentation Center, Iowa State University, Ames, Iowa 50011
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43
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Kientz CE. Chromatography and mass spectrometry of chemical warfare agents, toxins and related compounds: state of the art and future prospects. J Chromatogr A 1998; 814:1-23. [PMID: 9718684 DOI: 10.1016/s0021-9673(98)00338-0] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Methods for the identification of chemical warfare agents, toxins, bioregulators and related products are frequently reported in literature. These methods are often based on instrumental analysis using chromatography (gas and liquid) and mass spectrometry. Here, these instrumental techniques are discussed in several applications, new developments and trends based on a review of the literature published since 1990. Apart from new instrumental developments, it is shown that modern analytical chemistry can be successfully applied to perform identification in the broad field of analytes ranging from chemical to biological warfare agents.
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Affiliation(s)
- C E Kientz
- TNO Prins Maurits Laboratory, Rijswijk, The Netherlands
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44
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Dorsey JG, Cooper WT, Siles BA, Foley JP, Barth HG. Liquid Chromatography: Theory and Methodology. Anal Chem 1998. [DOI: 10.1021/a1980022h] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- John G. Dorsey
- Department of Chemistry, Florida State University, Tallahassee, Florida 32306-4390
| | - William T. Cooper
- Department of Chemistry, Florida State University, Tallahassee, Florida 32306-4390
| | - Barbara A. Siles
- Department of Chemistry, College of William and Mary, Williamsburg, Virginia 23187-8795
| | - Joe P. Foley
- Department of Chemistry, Villanova University, Villanova, Pennsylvania 19085-1699
| | - Howard G. Barth
- Central Research and Development Department, E. I. du Pont de Nemours & Company, P.O. Box 80228, Experimental Station, Wilmington, Delaware 19880
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45
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Quiñones I, Guiochon G. Extension of a Jovanovic-Freundlich isotherm model to multicomponent adsorption on heterogeneous surfaces. J Chromatogr A 1998; 796:15-40. [PMID: 9580124 DOI: 10.1016/s0021-9673(97)01096-0] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A recently proposed Jovanovic-Freundlich isotherm model for single component adsorption without lateral interactions on heterogeneous surfaces is extended to account for lateral interactions and for competitive adsorption. The model is tested using previously reported single component and competitive adsorption data of 2-phenylethanol and 3-phenylpropanol on ODS-silica with methanol-water as the mobile phase. A comparison is made regarding the ability of the Jovanovic-Freundlich and Langmuir-Freundlich models to predict competitive equilibria using the single component identified parameters. Fair predictions of the competitive data were obtained when using heterogeneous-surface models which do not take into account the possible interactions of phenylalcohols in the adsorbed phase via hydrogen bonding. Markedly improved predictions were obtained with models which account simultaneously for the two main sources of adsorbed phase nonideal behavior, i.e. adsorbate-adsorbate interactions and heterogeneity of the adsorbent surface.
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Affiliation(s)
- I Quiñones
- Department of Chemistry, University of Tennessee, Knoxville 37996-1600, USA
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46
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Walcarius A, Lamberts L. The Methylviologen-Doped Zeolite Modified Electrode as a New Detector for Suppressor Free Ion Chromatography. ANAL LETT 1998. [DOI: 10.1080/00032719808001863] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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47
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Enantioselective Separations. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0301-4770(08)60303-6] [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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48
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YAMADA S, MURABAYASHI K, NAKAMURA M. Inclusion Reaction of Some Fluorophores with .BETA.-Cyclodextrin and Its Effect on Their Reversed-Phase HPLC Retention. ANAL SCI 1998. [DOI: 10.2116/analsci.14.897] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Shinkichi YAMADA
- Laboratory of Analytical Chemistry, Faculty of Engineering, Shizuoka University
| | | | - Motoshi NAKAMURA
- Laboratory of Analytical Chemistry, Faculty of Engineering, Shizuoka University
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49
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Herraiz T. Sample preparation and reversed phase-high performance liquid chromatography analysis of food-derived peptides. Anal Chim Acta 1997. [DOI: 10.1016/s0003-2670(97)00199-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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50
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