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Hicks MB, Mattern K, Fine J, Grosser S, Patel D, Weisel L, Aggarwal P. Portable capillary LC for in-line UV monitoring and MS detection: Comparable sensitivity and much lower solvent consumption. J Sep Sci 2023; 46:e2300300. [PMID: 37715328 DOI: 10.1002/jssc.202300300] [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: 04/30/2023] [Revised: 08/26/2023] [Accepted: 08/29/2023] [Indexed: 09/17/2023]
Abstract
Pharmaceutical development currently relies on quality separation methods from early discovery through to line-of-site manufacturing. There have been significant advancements made regarding the column particle packing, internal diameter, length connectivity, the understanding of the impact key parameters like void volume, flow rate, and temperature all that affects the resultant separation quality, that is, resolution, peak shape, peak width, run time, and signal-to-noise ratio. There is however a strong need to establish better alternatives to large bulky high-performance liquid chromatography racks either for process analytical reaction monitoring or mass spectrometry analysis in establishing product quality. Compact, portable high-pressure liquid chromatography can be a more efficient alternative to traditional ultra-high pressure liquid chromatography and traditional liquid chromatography. The compact versatile instrument evaluated here allows good separation control with either the on-board column with fixed ultra-violet wavelength cartridge or for use with a high-resolution mass spectrometry. Significant space reduction results in greener lab spaces with improved energy efficiency for smaller labs with lower energy demands. In addition, this compact liquid chromatography was used as a portable reaction monitoring solution to compare forced degradation kinetics and assess portable liquid chromatography-mass spectrometry capability for the analyses required for pharmaceutical drug product testing.
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Affiliation(s)
- Michael B Hicks
- Analytical Research & Development, MRL, Merck & Co., Inc., Rahway, New Jersey, USA
| | - Keith Mattern
- Process Enabling Technologies, MRL, Merck & Co., Inc., Rahway, New Jersey, USA
| | - Jonathan Fine
- Analytical Research & Development, MRL, Merck & Co., Inc., Rahway, New Jersey, USA
| | - Shane Grosser
- Process Enabling Technologies, MRL, Merck & Co., Inc., Rahway, New Jersey, USA
| | - Daya Patel
- Analytical Research & Development, MRL, Merck & Co., Inc., Rahway, New Jersey, USA
| | - Lauren Weisel
- Analytical Research & Development, MRL, Merck & Co., Inc., Rahway, New Jersey, USA
| | - Pankaj Aggarwal
- Analytical Research & Development, MRL, Merck & Co., Inc., Massachusetts, Boston, USA
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2
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Cizmarova I, Matuskova M, Stefanik O, Horniakova A, Mikus P, Piestansky J. Determination of thiamine and pyridoxine in food supplements by a green ultrasensitive two-dimensional capillary electrophoresis hyphenated with mass spectrometry. CHEMICAL PAPERS 2022. [DOI: 10.1007/s11696-022-02309-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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3
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Suntornsuk L, Anurukvorakun O. Sensitivity enhancement in capillary electrophoresis and their applications for analyses of pharmaceutical and related biochemical substances. Electrophoresis 2021; 43:939-954. [PMID: 34902168 DOI: 10.1002/elps.202100236] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 11/23/2021] [Accepted: 11/30/2021] [Indexed: 11/11/2022]
Abstract
This review aims to illustrate sensitivity enhancement methods in capillary electrophoresis (CE) and their applications for pharmaceutical and related biochemical substance analyses. The first two parts of the article describe the introduction and principle of CE. The main part focuses on strategies for sensitivity improvement in CE including detector and capillary technologies and pre-concentration techniques. Applications of these techniques for pharmaceutical and biomedical substance analyses are surveyed during the years 2018-2021. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Leena Suntornsuk
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Mahidol University, Bangkok, 10400, Thailand
| | - Oraphan Anurukvorakun
- Department of Cosmetic Science, Phranakorn Rajabhat University, Bangkok, 10220, Thailand
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4
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A Comprehensive Review on Assessment and Key Control Strategies for Impurities in Drug Development with a Special Emphasis on Post-marketing Surveillance. J Pharm Innov 2021. [DOI: 10.1007/s12247-021-09607-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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5
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Kumar R, Guttman A, Rathore AS. Applications of capillary electrophoresis for biopharmaceutical product characterization. Electrophoresis 2021; 43:143-166. [PMID: 34591322 DOI: 10.1002/elps.202100182] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/07/2021] [Accepted: 09/23/2021] [Indexed: 12/16/2022]
Abstract
Capillary electrophoresis (CE), after being introduced several decades ago, has carved out a niche for itself in the field of analytical characterization of biopharmaceutical products. It does not only offer fast separation, high resolution in miniaturized format, but equally importantly represents an orthogonal separation mechanism to high-performance liquid chromatography. Therefore, it is not surprising that CE-based methods can be found in all major pharmacopoeias and are recommended for the analysis of biopharmaceutical products during process development, characterization, quality control, and release testing. Different separation formats of CE, such as capillary gel electrophoresis, capillary isoelectric focusing, and capillary zone electrophoresis are widely used for size and charge heterogeneity characterization as well as purity and stability testing of therapeutic proteins. Hyphenation of CE with MS is emerging as a promising bioanalytical tool to assess the primary structure of therapeutic proteins along with any impurities. In this review, we confer the latest developments in capillary electrophoresis, used for the characterization of critical quality attributes of biopharmaceutical products covering the past 6 years (2015-2021). Monoclonal antibodies, due to their significant share in the market, have been given prioritized coverage.
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Affiliation(s)
- Ramesh Kumar
- Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
| | - Andras Guttman
- Horváth Csaba Memorial Laboratories of Bioseparation Sciences, Research Center for Molecular Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary.,Translational Glycomics Group, Research Institute of Biomolecular and Chemical Engineering, University of Pannonia, Veszprem, Hungary
| | - Anurag S Rathore
- Department of Chemical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India
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6
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Harnessing the power of electrophoresis and chromatography: Offline coupling of reverse phase liquid chromatography-capillary zone electrophoresis-tandem mass spectrometry for peptide mapping for monoclonal antibodies. J Chromatogr A 2020; 1620:460954. [DOI: 10.1016/j.chroma.2020.460954] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/05/2020] [Accepted: 02/06/2020] [Indexed: 12/30/2022]
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7
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Xu Z, Xue T, He T. Investigation on the chiral recognition mechanism between verteporfin and cholate salts by capillary electrophoresis. J Sep Sci 2020; 43:2905-2913. [DOI: 10.1002/jssc.202000026] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Revised: 04/04/2020] [Accepted: 04/14/2020] [Indexed: 01/08/2023]
Affiliation(s)
- Zhongqi Xu
- College of ChemistryChemical Engineering and BiotechnologyDonghua University Shanghai 201620 P. R. China
| | - Tianfeng Xue
- College of ChemistryChemical Engineering and BiotechnologyDonghua University Shanghai 201620 P. R. China
| | - Tao He
- College of ChemistryChemical Engineering and BiotechnologyDonghua University Shanghai 201620 P. R. China
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8
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Capillary electrophoresis fingerprints combined with Linear Quantitative Profiling Method to monitor the quality consistency and predict the antioxidant activity of Alkaloids of Sophora flavescens. J Chromatogr B Analyt Technol Biomed Life Sci 2019; 1133:121827. [PMID: 31756622 DOI: 10.1016/j.jchromb.2019.121827] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 10/08/2019] [Accepted: 10/08/2019] [Indexed: 01/07/2023]
Abstract
Alkaloids of Sophora flavescens (ASF) has various pharmacological effects, and it is widely used in clinical practice. The aim of this research was to develop an environmentally friendly methodology that enables not only identification but also the quality consistency assessment of Alkaloids of Sophora flavescens. A background electrolyte composed of 50 mmol/L sodium tetraborate solution, 500 mmol/L boric acid and 1.2 mmol/L citric acid was used to conduct the fingerprint analysis coupled with quantitative determination of three components. Linear quantitative profiling method was used for comprehensive quality discrimination of the test samples from both qualitative and quantitative perspectives, and the 27 batches of samples were well differentiated. In addition, the fingerprint-efficacy relationship between chemical components and antioxidant activity in vitro was established using partial least squares regression model, which provided important medicinal efficacy information for quality control.
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9
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Konop M, Kłodzińska E, Borowiec J, Laskowska AK, Czuwara J, Konieczka P, Cieślik B, Waraksa E, Rudnicka L. Application of micellar electrokinetic chromatography for detection of silver nanoparticles released from wound dressing. Electrophoresis 2019; 40:1565-1572. [PMID: 30848499 DOI: 10.1002/elps.201900020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Revised: 02/28/2019] [Accepted: 03/01/2019] [Indexed: 11/07/2022]
Abstract
The recent emergence of nanotechnology has provided a new therapeutic modality in case of silver nanoparticles. Dressings containing silver form the basis for the treatment of burns and wounds, either acute or chronic ones. The aim of the study was to examine silver release from the different wound dressings: commercially available (Atrauman Ag, Aquacel Ag) and experimental (FKDP-AgNPs) using MEKC. In order to characterize prepared keratin based wound dressing before and after its modification with AgNPs, a compositional analysis was conducted using energy dispersive X-ray spectroscopy. Nanosilver toxicity was evaluated with the 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4 sulfophenyl)-2H-tetrazolium test. Silver release from wound dressings was assessed using MEKC. The best separation was observed for MEKC in 20 mM borate buffer at pH 9 with 20 mM SDS addition. In vitro studies showed silver at higher concentration than 10 ppm exerted a toxic effect on fibroblasts isolated from diabetic mice versus. NIH/3T3 and BJ cell lines (p < 0.05). We observed silver was released more gradually from experimental FKDP-AgNPs wound dressing, in compare to commercially available wound dressings. The fast and low-cost method utilizing MEKC can be used in clinical practice to detect silver release from the wound dressings.
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Affiliation(s)
- Marek Konop
- Department of Experimental Physiology and Pathophysiology, Medical University of Warsaw, Warsaw, Poland.,Department of Dermatology, Medical University of Warsaw, Warsaw, Poland.,Department of Neuropeptides, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Ewa Kłodzińska
- Department of Analytical Chemistry and Instrumental Analysis, Institute of Sport - National Research Institute, Warsaw, Poland
| | - Joanna Borowiec
- College of Physical Science and Technology, and Sino-British Materials Research, Institute, Sichuan University, Chengdu, P. R. China
| | - Anna Katarzyna Laskowska
- Department of Neuropeptides, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
| | - Joanna Czuwara
- Department of Dermatology, Medical University of Warsaw, Warsaw, Poland
| | - Piotr Konieczka
- Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gdańsk, Poland
| | - Bartłomiej Cieślik
- Department of Analytical Chemistry, Faculty of Chemistry, Gdańsk University of Technology, Gdańsk, Poland
| | - Emilia Waraksa
- Department of Analytical Chemistry and Instrumental Analysis, Institute of Sport - National Research Institute, Warsaw, Poland
| | - Lidia Rudnicka
- Department of Dermatology, Medical University of Warsaw, Warsaw, Poland.,Department of Neuropeptides, Mossakowski Medical Research Centre, Polish Academy of Sciences, Warsaw, Poland
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10
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Maruszak W, Cybulski M. Simultaneous determination of the counter ion and possible impurity from the synthetic route in the pharmaceutical substance prasugrel hydrochloride. J Pharm Biomed Anal 2015; 105:32-38. [DOI: 10.1016/j.jpba.2014.11.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Revised: 11/04/2014] [Accepted: 11/07/2014] [Indexed: 11/24/2022]
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11
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Ciurba A, Hancu G, Cojocea LM, Sipos E, Todoran N. Development of new formulation and its evaluation by capillary electrophoresis of tablets containing tramadol hydrochloride and paracetamol. Pharm Dev Technol 2013; 19:833-8. [DOI: 10.3109/10837450.2013.836219] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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12
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Shen X, Chen X, Tabor DE, Liu Y, Albarghouthi M, Zhang YF, Galinski MS. Size analysis of residual host cell DNA in cell culture-produced vaccines by capillary gel electrophoresis. Biologicals 2013; 41:201-8. [DOI: 10.1016/j.biologicals.2012.12.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 11/27/2012] [Accepted: 12/04/2012] [Indexed: 12/19/2022] Open
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13
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Yang G, Li W, Pan Y, Tu X. Rapid Simultaneous Determination of Four Alkaloids in Lotus Plumule by CZE with Ephedrine Hydrochloride as an Internal Standard. Chromatographia 2012. [DOI: 10.1007/s10337-012-2312-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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Separation of Steroids and the Determination of Estradiol Content in Transdermic Patches by Microemulsion Electrokinetic Chromatography. Chromatographia 2011. [DOI: 10.1007/s10337-010-1899-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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15
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Hałka A, Płocharz P, Torbicz A, Dzido T. Reversed-phase pressurized planar electrochromatography and planar chromatography of acetylsalicylic acid, caffeine, and acetaminophen. JPC-J PLANAR CHROMAT 2010. [DOI: 10.1556/jpc.23.2010.6.7] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Comparison of chiral electrophoretic separation methods for phenethylamines and application on impurity analysis. J Pharm Biomed Anal 2010; 53:1201-9. [DOI: 10.1016/j.jpba.2010.06.025] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2010] [Revised: 06/21/2010] [Accepted: 06/22/2010] [Indexed: 11/20/2022]
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17
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Fundamental aspects of chiral electromigration techniques and application in pharmaceutical and biomedical analysis. J Pharm Biomed Anal 2010; 55:688-701. [PMID: 21131154 DOI: 10.1016/j.jpba.2010.11.018] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2010] [Revised: 11/11/2010] [Accepted: 11/12/2010] [Indexed: 11/23/2022]
Abstract
Capillary electromigration techniques are often considered ideal methods for the analysis of chiral compounds due to the high resolution power and flexibility of the technique. Therefore, especially capillary electrophoresis using a chiral selector in the background electrolyte, also termed electrokinetic chromatography, has found widespread acceptance in analytical enantioseparations of drug compounds in pharmaceuticals and biological media. Moreover, mechanistic studies on analyte complexation by the chiral selectors have continuously been conducted in an effort to rationalize enantioseparation phenomena. These studies combined capillary electrophoresis with spectroscopic techniques such as nuclear magnetic resonance and/or molecular modeling. The present review focuses on recent examples of mechanistic aspects of capillary electromigration enantioseparations and summarizes recent applications of chiral pharmaceutical and biomedical analysis published between January 2009 and August 2010.
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18
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Recent advances of capillary electrophoresis in pharmaceutical analysis. Anal Bioanal Chem 2010; 398:29-52. [DOI: 10.1007/s00216-010-3741-5] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 04/08/2010] [Accepted: 04/09/2010] [Indexed: 01/16/2023]
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19
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Chen J, Du Y, Zhu F, Chen B. Glycogen: A novel branched polysaccharide chiral selector in CE. Electrophoresis 2010; 31:1044-50. [DOI: 10.1002/elps.200900534] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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20
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Multiple Chromatographic and Chemometric Methods for Quality Standardisation of Chinese Herbal Medicines. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/s1876-3553(11)60003-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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21
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Sánchez-Hernández L, GarcÃa-Ruiz C, Luisa Marina M, Luis Crego A. Recent approaches for enhancing sensitivity in enantioseparations by CE. Electrophoresis 2010; 31:28-43. [DOI: 10.1002/elps.200900429] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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23
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Huhn C, Ramautar R, Wuhrer M, Somsen GW. Relevance and use of capillary coatings in capillary electrophoresis–mass spectrometry. Anal Bioanal Chem 2009; 396:297-314. [DOI: 10.1007/s00216-009-3193-y] [Citation(s) in RCA: 154] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 09/22/2009] [Accepted: 09/24/2009] [Indexed: 11/24/2022]
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24
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Ikai T, Okamoto Y. Structure Control of Polysaccharide Derivatives for Efficient Separation of Enantiomers by Chromatography. Chem Rev 2009; 109:6077-101. [DOI: 10.1021/cr8005558] [Citation(s) in RCA: 347] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Tomoyuki Ikai
- EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan, and College of Material Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St. Harbin 150001, P. R. China
| | - Yoshio Okamoto
- EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan, and College of Material Science and Chemical Engineering, Harbin Engineering University, 145 Nantong St. Harbin 150001, P. R. China
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25
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Nishikawa F, Murakami K, Matsugami A, Katahira M, Nishikawa S. Structural studies of an RNA aptamer containing GGA repeats under ionic conditions using microchip electrophoresis, circular dichroism, and 1D-NMR. Oligonucleotides 2009; 19:179-90. [PMID: 19355811 DOI: 10.1089/oli.2008.0167] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Nuclear magnetic resonance (NMR) studies have shown that RNA/DNA oligomers with GGA repeat sequences contain unique G-quadruplex structures in the presence of K(+) or Na(+) ions. In this study, we used microchip electrophoresis to study the structure of an RNA aptamer against bovine prion protein that possessed four GGA-triplet repeats (wt2). We analyzed the structural changes and characterized dimer formation of the aptamer. Mutational, circular dichroism, and one-dimensional NMR studies of wt2 revealed that K(+) ions induce wt2 to assume a thermostable dimer in an intramolecular G-quadruplex with parallel orientation.
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Affiliation(s)
- Fumiko Nishikawa
- Age Dimension Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Ibaraki, Japan
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26
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Gencoglu A, Minerick A. Chemical and morphological changes on platinum microelectrode surfaces in AC and DC fields with biological buffer solutions. LAB ON A CHIP 2009; 9:1866-73. [PMID: 19532961 DOI: 10.1039/b820126a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Platinum is widely considered a noncorrodible and inert microelectrode material for many electrokinetic microdevice applications. However, platinum reactions are well documented in the literature. Reproducibility of cellular electrokinetic microdevice responses were inconsistent and suggested a dependance on platinum microelectrode function with exposure time in electric fields. Chemical and morphological changes on the surface of platinum microelectrodes in 1 V(pp)/175 microm and 6 V(pp)/175 microm AC and +/-3 V/175 microm DC electric fields in the presence of five biological buffer solutions were investigated. Platinum dissolution, platinum redeposition, chloride formation and oxide formation on platinum microelectrode surfaces were observed by scanning electron microscopy and energy dispersive spectroscopy under ordinary microdevice conditions and verified by cyclic voltammetry studies. X-ray photoelectron spectroscopy showed the presence of oxygen and oxidation of platinum on microelectrode surfaces. Changes were more severe in a 6 V(pp)/175 microm AC field than in a 1 V(pp)/175 microm AC field, and more severe in +/-3 V/175 microm DC fields than in a 6 V(pp)/175 microm AC field.
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Affiliation(s)
- Aytug Gencoglu
- Dave C. Swalm School of Chemical Engineering, Mississippi State University, Mississippi State 39762, USA
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27
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Lodén H, Pettersson C, Arvidsson T, Amini A. Quantitative determination of salbutamol in tablets by multiple-injection capillary zone electrophoresis. J Chromatogr A 2008; 1207:181-5. [DOI: 10.1016/j.chroma.2008.08.082] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 08/11/2008] [Accepted: 08/14/2008] [Indexed: 11/28/2022]
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28
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Otieno AC, Mwongela SM. Capillary electrophoresis-based methods for the determination of lipids--a review. Anal Chim Acta 2008; 624:163-74. [PMID: 18706322 DOI: 10.1016/j.aca.2008.06.026] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2008] [Revised: 06/12/2008] [Accepted: 06/17/2008] [Indexed: 01/08/2023]
Abstract
Capillary electrophoresis (CE) is a high-resolution technique for the separation of complex biological and chemical mixtures. CE continues to emerge as a powerful tool in the determination of lipids. Here we review the analytical potential of CE for the determination of a wide range of lipids. The different classes of lipids are introduced, and the different modes of CE and optimization methods for the separation of lipids are described. The advantages and disadvantages of the different modes of CE compared to traditional methods like gas chromatography (GC) and liquid chromatography (LC) in the determination of lipids are discussed. Finally, the potential of CE in the determination of lipids in the future is illustrated.
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Affiliation(s)
- Anthony C Otieno
- Department of Chemistry, Kent State University, Kent, OH 44242, USA
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29
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Affiliation(s)
- Timothy J Ward
- Millsaps College 1701 North State Street, Box 150306, Jackson, Mississippi 39210, USA.
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