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Wu Y, Li Y, Li S, Ma Y, Ji W, Sun Y. The series of L-lysine-derived gelators-modified multifunctional chromatography stationary phase for separation of chiral and achiral compounds. J Chromatogr A 2024; 1733:465228. [PMID: 39163701 DOI: 10.1016/j.chroma.2024.465228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Revised: 08/02/2024] [Accepted: 08/05/2024] [Indexed: 08/22/2024]
Abstract
In this study, using chiral L-lysine as the molecular skeleton, three kinds of L-lysine-derived gelators (GBLB, GBLF and GFLF) were synthesized and then bonded to the surface of silica matrix (5 μm) by amide condensation to prepare a series of multifunctional chromatography stationary phases (GBLB-SiO2, GBLF-SiO2, and GFLF-SiO2) were prepared. The L-lysine-derived gelators not only possess chiral recognition ability, but also can spontaneously form oriented and ordered network structures in liquid medium through the interaction of non-covalent bonding forces such as hydrogen bonding, π-π stacking, and van der Waals forces. The comprehensive effect of multiple weak interaction sites enhances the molecular recognition ability and further improves the separation diversity of different types of compounds on stationary phases. The separation and evaluation of chiral compounds showed that benzoin, 1-phenyl-ethanol, 1-phenyl-propanol and 6-hydroxyflavanone could be separated in normal phase mode (NPLC). The separation of different types of non-chiral compounds, such as sulfonamides, nucleosides, nucleobases, polycyclic aromatic hydrocarbons (PAHs), anilines, and aromatic acids, were achieved in hydrophilic interaction/reversed-phase/ion-exchange mode (HILIC/RPLC/IEC), and the separation of polarized compounds could be performed under the condition of ultrapure water as the mobile phase, which has the typical retention characteristics of per aqueous liquid chromatography (PALC). The effects of organic solvent content, temperature, pH value, and buffer salt concentration on the retention and separation performance of the column were investigated. Comparison of the three prepared columns showed that the separation performance (such as aromatic selectivity) could be improved by increasing the types of functional groups on the surface of the stationary phase and the number of aromatic groups. In a word, the prepared stationary phase have multiple retention properties, can simultaneously separate chiral compounds and various types of achiral compounds. This work provides an idea for developing multifunctional liquid chromatography stationary phase materials, and further expands the application of gelators in separation science.
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Affiliation(s)
- Yongli Wu
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China
| | - Yuanyuan Li
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China.
| | - Shaorong Li
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China
| | - Yulong Ma
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China
| | - Wenxin Ji
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China
| | - Yonggang Sun
- State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering, College of Chemistry and Chemical Engineering, Ningxia University, Yinchuan, 750021, China
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Xu M, Wu Z. A mixed-mode reversed-phase/strong-anion-exchange stationary phase: Analyte-retention stability and application in the analysis of nonsteroidal anti-inflammatory drugs. J Chromatogr A 2024; 1722:464871. [PMID: 38593520 DOI: 10.1016/j.chroma.2024.464871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 04/01/2024] [Accepted: 04/03/2024] [Indexed: 04/11/2024]
Abstract
Mixed-mode reversed-phase/anion-exchange chromatography (RP/AEX) is an effective method for the chromatographic analysis of acidic drugs because it combines reversed-phase chromatography (RP) with anion-exchange chromatography (AEX). However, the result repeatability for the RP/AEX analysis of acidic drugs is frequently compromised by the detrimental effects of residual silanol groups in an RP/AEX stationary phase on peak separation and analyte retention. In this study, an RP/weak-AEX stationary phase with amino anion-exchange groups, Sil-AA, was prepared. Subsequently, an RP/strong-AEX stationary phase, Sil-PBQA, was prepared by replacing the amino groups in Sil-AA with a benzene ring and a benzyl-containing quaternary ammonium salt. The chromatographic behaviors of Sil-PBQA and Sil-AA were compared, and the effect of residual silanol groups on the chromatographic behavior of an RP/AEX stationary phase was evaluated. Residual silanol groups not only caused additional electrostatic interactions for acidic analytes, but also competed with the analytes for the anion-exchange sites in an RP/AEX stationary phase. The effects of different salt-containing mobile-phase systems on the analyte-retention behavior of Sil-PBQA were investigated to develop a method that enhanced the repeatability of the RP/AEX acidic-analyte-analysis results obtained using Sil-PBQA and facilitated the separation of nonsteroidal anti-inflammatory drugs on Sil-PBQA. The ideas presented in this paper can improve the separation of peaks and repeatability of results in the RP/AEX analysis of acidic drugs.
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Affiliation(s)
- Meng Xu
- School of Pharmaceutical Science & Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China.
| | - Zhenwei Wu
- School of Pharmaceutical Science & Technology, Tianjin University, 92 Weijin Road, Tianjin 300072, China
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3
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Walter TH, Yang J. Assessment of the reproducibility of a C 18 bonded phase based on ethylene-bridged hybrid organic/inorganic particles. J Chromatogr A 2024; 1716:464637. [PMID: 38217961 DOI: 10.1016/j.chroma.2024.464637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 01/05/2024] [Accepted: 01/07/2024] [Indexed: 01/15/2024]
Abstract
The batch-to-batch reproducibility of an endcapped trifunctional C18 bonded phase based on ethylene-bridged hybrid particles was assessed using a modified version of a chromatographic test developed by Neue and coworkers. The test involves the isocratic separation of six compounds chosen to probe different characteristics of the stationary phase, including hydrophobicity, hydrogen bonding and cation-exchange. The assessment was based on results for a total of 471 batches manufactured and tested over a 19 year time span. The results were compared to those for an endcapped monofunctional C18 bonded phase on silica particles, based on results generated for 246 batches over 29 years. Overall, both stationary phases show similar reproducibility, with relative standard deviations for the relative retentions ranging from 0.1 to 3.2 %.
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Affiliation(s)
- Thomas H Walter
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA.
| | - Jun Yang
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
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4
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De Saegher T, Vercammen J, Atanasova B, Van Geem KM, De Clercq J, Verberckmoes A, Lauwaert J. Efficient mapping of lignin depolymerization product pools and quantification of specific monomers through rapid GPC-HPLC-UV/VIS analysis. Anal Chim Acta 2023; 1278:341738. [PMID: 37709433 DOI: 10.1016/j.aca.2023.341738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/16/2023] [Accepted: 08/17/2023] [Indexed: 09/16/2023]
Abstract
BACKGROUND Growing research on lignin depolymerization to functionalized bio-aromatics has necessitated dedicated analysis techniques. However, immense variability in molecular weight and functional groups of the depolymerization products impedes fast analysis of a large number of samples while remaining in-depth enough for catalyst screening or reaction condition optimization. While GPC-HPLC-UV/VIS has been a promising technique, up until now, the information it provides is largely qualitative. By enabling quantification of key monomeric products and through further reduction of overall analysis time, this study aims to increase the potential of GPC-HPLC-UV/VIS for fast and in-depth characterization of lignin depolymerization product pools. RESULTS Analysis of selected samples, isolated from GPC-HPLC-UV/VIS analyses of lignin depolymerization product pools, with gas chromatography (GC) equipped with an Orbitrap high-resolution accurate mass spectrometer (Orbitrap-HR/AM-MS) is successful in identifying the main low monomeric products. Moreover, these identifications are further substantiated through GPC-HPLC-UV/VIS analysis of standards. Furthermore, straight forward quantification of these products directly within GPC-HPLC-UV/VIS is successfully developed with limits of detection ≤0.05 mmol/L, which is at least on par with more complex analysis techniques. Additionally, several different reversed phase columns are assessed to reduce 2nd dimension (2D) time and, hence, overall analysis time while maintaining the possibility for quantification. A reduction in overall analysis time of about 30% as compared to the state-of-the-art is achieved by using a YMC Triart BIO C4 column as 2D. SIGNIFICANCE Through the enhancements introduced in this study, GPC-HPLC-UV/VIS emerges as a unique technique for the analysis of lignin depolymerization product pools, which is capable of fast yet sufficiently in-depth analysis of a large volume of samples. This capability is indispensable for catalyst screening and fine-tuning reaction conditions.
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Affiliation(s)
- Tibo De Saegher
- Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - Joeri Vercammen
- Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium; Interscience Expert Center (IS-X), Avenue J.E. Lenoir 2, 1384, Louvain-la-Neuve, Belgium
| | - Boyana Atanasova
- Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - Kevin M Van Geem
- Laboratory for Chemical Technology (LCT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Technologiepark 125, 9052, Ghent, Belgium
| | - Jeriffa De Clercq
- Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - An Verberckmoes
- Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium
| | - Jeroen Lauwaert
- Industrial Catalysis and Adsorption Technology (INCAT), Department of Materials Textiles and Chemical Engineering (MaTCh), Ghent University, Valentin Vaerwyckweg 1, 9000, Ghent, Belgium.
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Deineka VI, Oleinits EY, Kulchenko YY, Blinova IP, Deineka LA. Chromatographic Separation and Determination of Anthocyanins under Conditions of Reversed Phase Chromatography, When Used As Mobile Phases of Acetonitrile–Formic Acid/Phosphoric Acid–Water Systems. RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A 2021. [DOI: 10.1134/s0036024421080094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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6
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Walter TH, Alden BA, Field JA, Lawrence NL, Osterman DL, Patel AV, DeLoffi MA. Characterization of a highly stable mixed-mode reversed-phase/weak anion-exchange stationary phase based on hybrid organic/inorganic particles. J Sep Sci 2021; 44:1005-1014. [PMID: 33354922 PMCID: PMC7986357 DOI: 10.1002/jssc.202001136] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 12/18/2020] [Accepted: 12/20/2020] [Indexed: 12/18/2022]
Abstract
We have characterized Atlantis ethylene-bridged hybrid C18 anion-exchange, a mixed-mode reversed-phase/weak anion-exchange stationary phase designed to give greater retention for anions (e.g., ionized acids) compared to conventional reversed-phase materials. The retention and selectivity of this stationary phase were compared to that of three benchmark materials, using a mixture of six polar compounds that includes an acid, two bases, and three neutrals. The compatibility of the ethylene-bridged hybrid C18 anion-exchange material with 100% aqueous mobile phases was also evaluated. We investigated the batch-to-batch reproducibility of the ethylene-bridged hybrid C18 anion-exchange stationary phase for 27 batches across three different particle sizes (1.7, 2.5, and 5 μm) and found it to be comparable to that of one of the most reproducible C18 stationary phases. We also characterized the acid and base stability of the ethylene-bridged hybrid C18 anion-exchange stationary phase and the results show it to be usable over a wide pH range, from 2 to 10. The extended upper pH limit relative to silica-based reversed-phase/weak anion-exchange materials is enabled by the use of ethylene-bridged hybrid organic/inorganic particles. The improved base stability allows Atlantis ethylene-bridged hybrid C18 anion-exchange to be used with a wider range of mobile phase pH values, opening up a greater range of selectivity options.
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7
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Cain CN, Forzano AV, Rutan SC, Collinson MM. Destructive stationary phase gradients for reversed-phase/hydrophilic interaction liquid chromatography. J Chromatogr A 2018; 1570:82-90. [DOI: 10.1016/j.chroma.2018.07.073] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 07/24/2018] [Accepted: 07/26/2018] [Indexed: 02/05/2023]
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8
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Sierra-Martin B, Fernandez-Barbero A. Inorganic/polymer hybrid nanoparticles for sensing applications. Adv Colloid Interface Sci 2016; 233:25-37. [PMID: 26782148 DOI: 10.1016/j.cis.2015.12.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Revised: 11/30/2015] [Accepted: 12/01/2015] [Indexed: 10/22/2022]
Abstract
This paper reviews a wide set of sensing applications based on the special properties associated with inorganic/polymer composite nanoparticles. We first describe optical sensing applications performed with hybrid nanoparticles and hybrid microgels with special emphasis on photoluminescence detection and imaging. Analyte detection with molecularly imprinted polymers and HPLC-based sensing using hybrid nanoparticles as stationary phase is also summarized. The final part is devoted to the study of ultra-sensitive molecule detection by surface-enhanced Raman spectroscopy using core-shell hybrid materials composed of noble metal nanoparticles and cross-linked polymers.
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9
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Song H, Desmet G, Cabooter D. Evaluation of the Kinetic Performance Differences between Hydrophilic-Interaction Liquid Chromatography and Reversed-Phase Liquid Chromatography under Conditions of Identical Packing Structure. Anal Chem 2015; 87:12331-9. [DOI: 10.1021/acs.analchem.5b03697] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Huiying Song
- Department
for Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, KU Leuven, Herestraat 49, Leuven, Belgium
| | - Gert Desmet
- Department
of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussel, Belgium
| | - Deirdre Cabooter
- Department
for Pharmaceutical and Pharmacological Sciences, Pharmaceutical Analysis, KU Leuven, Herestraat 49, Leuven, Belgium
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10
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Borges EM, Volmer DA. Silica, Hybrid Silica, Hydride Silica and Non-Silica Stationary Phases for Liquid Chromatography. Part II: Chemical and Thermal Stability. J Chromatogr Sci 2015; 53:1107-22. [DOI: 10.1093/chromsci/bmu173] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Indexed: 12/28/2022]
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11
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Borges EM, Euerby MR. An appraisal of the chemical and thermal stability of silica based reversed-phase liquid chromatographic stationary phases employed within the pharmaceutical environment. J Pharm Biomed Anal 2013; 77:100-15. [DOI: 10.1016/j.jpba.2013.01.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 01/04/2013] [Accepted: 01/05/2013] [Indexed: 10/27/2022]
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12
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Blotevogel J, Borch T. Determination of hexamethylphosphoramide and other highly polar phosphoramides in water samples using reversed-phase liquid chromatography/electrospray ionization time-of-flight mass spectrometry. J Chromatogr A 2011; 1218:6426-32. [DOI: 10.1016/j.chroma.2011.07.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2011] [Revised: 07/06/2011] [Accepted: 07/07/2011] [Indexed: 10/17/2022]
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13
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Borges EM, Collins CH. Characterization of several stationary phases prepared by thermal immobilization of poly(methyltetradecylsiloxane) onto silica surfaces. J Chromatogr A 2011; 1218:4378-88. [DOI: 10.1016/j.chroma.2011.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Revised: 02/21/2011] [Accepted: 05/09/2011] [Indexed: 11/25/2022]
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14
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Borges EM, Collins CH. Chromatographic evaluation using basic solutes of the silanol activity of stationary phases based on poly(methyloctylsiloxane) immobilized onto silica. J Sep Sci 2011; 34:1141-8. [DOI: 10.1002/jssc.201000700] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Revised: 02/22/2011] [Accepted: 02/24/2011] [Indexed: 11/07/2022]
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15
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A new generation of more pH stable reversed phases prepared by silanization of zirconized silica. J Chromatogr A 2008; 1191:90-8. [DOI: 10.1016/j.chroma.2008.01.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2007] [Revised: 01/07/2008] [Accepted: 01/08/2008] [Indexed: 11/17/2022]
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16
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Silva CR, Collins CH, Collins KE, Airoldi C. An overview of the chromatographic properties and stability of C18 titanized phases. J Sep Sci 2006; 29:790-800. [PMID: 16830491 DOI: 10.1002/jssc.200500479] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Phases based on titanized silicas are an alternative in the search for HPLC stationary phases with enhanced pH stability. This technology explores the chemical modification of the bare silica surface by grafting a titanium oxide layer with the objective of retarding the dissolution of the support in alkaline mobile phases, followed by C18 silanization. The present manuscript describes recent work on the development of chemically bonded titanized phases, including phases containing embedded urea groups, and phases prepared both in the absence and in the presence of a monolayer of water preadsorbed onto the bare silica. The advantages and disadvantages of these alternative C18 titanized phases are discussed, taking into account their chromatographic properties accessed by some common test procedures. Column lifetimes, measured by accelerated aging tests using aggressive conditions, such as high-pH phosphate mobile phases and elevated temperature, are also discussed.
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Affiliation(s)
- César R Silva
- Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
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Albert M, Cretier G, Guillarme D, Heinisch S, Rocca JL. Some advantages of high temperature for the separation of pharmaceutical compounds with mass spectrometry detection. J Sep Sci 2005; 28:1803-11. [PMID: 16224976 DOI: 10.1002/jssc.200500145] [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: 11/09/2022]
Abstract
The beneficial effects of high temperature on separation and detection of basic compounds, the detection being performed by MS via ESI, are investigated. The influence of various parameters on both separation and detection performances is studied. These parameters include the mobile phase pH, the temperature, and the type of stationary phase. Experiments are performed under gradient elution conditions. The results obtained with four different supports, silica-, zirconia-, carbon-, and polymer-based columns, are compared by means of different criteria including the elution composition, the peak asymmetry, and the S/N. High temperature liquid chromatography at high pH with volatile buffers suitable for MS detection was shown to be an interesting choice for solutes with basic sites.
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Affiliation(s)
- Monique Albert
- Laboratoire des Sciences Analytiques, Université Claude Bernard-Lyon 1, Villeurbanne, France
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18
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Neue UD, Tran K, Méndez A, Carr PW. The combined effect of silanols and the reversed-phase ligand on the retention of positively charged analytes. J Chromatogr A 2005; 1063:35-45. [PMID: 15700455 DOI: 10.1016/j.chroma.2004.11.096] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The nature of the interaction of positively charged analytes with the surface of reversed-phase bonded phases has been investigated as a function of both pH and volume fraction of organic modifier. Studies of the combined effect of both the parameters have been previously reported by us, and the data presented here further demonstrate a multiplicative interaction between pH and the concentration of organic modifier in the mobile phase. Fitting of the data as functions of pH and eluent composition clearly shows that the hydrophobically assisted ion-exchange process dominates over a purely reversed-phase or a pure ion-exchange retention mechanism. The underlying theory is developed in detail, and the mechanism is elucidated using several reversed-phase packings of substantially different character.
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Affiliation(s)
- Uwe D Neue
- Waters Corporation, Milford, MA 01757-3696, USA.
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