1
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Böhm D, Koall M, Matysik FM. Combining amperometry and mass spectrometry as a dual detection approach for capillary electrophoresis. Electrophoresis 2023; 44:492-500. [PMID: 36413610 DOI: 10.1002/elps.202200228] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 10/30/2022] [Accepted: 11/11/2022] [Indexed: 11/23/2022]
Abstract
Dual detection concepts (DDCs) are becoming more and more popular in analytical chemistry. In this work, we describe a novel DDC for capillary electrophoresis (CE) consisting of an amperometric detector (AD) and a mass spectrometer (MS). This detector combination has a good complementarity as the AD exhibits high sensitivity, whereas the MS provides excellent selectivity. Both detectors are based on a destructive detection principle, making a serial detector arrangement impossible. Thus, for the realization of the DDC, the CE flow was divided into two parts with a flow splitter. The DDC was characterized in a proof-of-concept study with ferrocene derivates and a nonaqueous background electrolyte. We could show that splitting the CE flow was a suitable method for the instrumental realization of the DDC consisting of two destructive detectors. By lowering the height of the AD compared to the MS, it was possible to synchronize the detector responses. Additionally, for the chosen model system, we confirmed that the AD was much more reproducible and had lower limits of detection (LODs) than the MS. The LODs were identical for the DDC and the single-detection arrangements, indicating no sensitivity decrease due to the CE flow splitting. The DDC was successfully applied to determine the drug and doping agent trimetazidine.
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Affiliation(s)
- Daniel Böhm
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, Regensburg, Germany
| | - Martin Koall
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, Regensburg, Germany
| | - Frank-Michael Matysik
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Universitätsstraße 31, Regensburg, Germany
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2
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Lin B, Chen J, Zeng Y, Li L, Qiu B, Lin Z, Guo L. A Facile Approach for On-Site Evaluation of Nicotine in Tobacco and Environmental Tobacco Smoke. ACS Sens 2019; 4:1844-1850. [PMID: 31250643 DOI: 10.1021/acssensors.9b00619] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Nicotine is highly addictive and harmful. It is one of the main active ingredients in tobacco and a major pollutant in environmental tobacco smoke. Thus, it is important to detect the nicotine content in tobacco and to monitor the nicotine content in environmental tobacco smoke. However, until present, there still has been no effective device for on-site determination of nicotine content in tobacco and environmental tobacco smoke. In this work, a portable device is fabricated for sensitive on-site evaluation of nicotine in tobacco and environmental tobacco smoke based on surface-enhanced Raman scattering (SERS). The weight of the entire device is less than 1 kg, and it uses a chargeable battery to drive both the pump and the Raman spectrometer. The total analysis time can be completed within 3-5 min. Thus, it has great potential for on-site analysis of nicotine in tobacco and environmental tobacco smoke.
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Affiliation(s)
- Bingyong Lin
- Institute of Nanomedicine and Nanobiosensing, MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, and College of Chemistry , Fuzhou University , Fuzhou , 350116 , China
| | - Jiaming Chen
- Institute of Nanomedicine and Nanobiosensing, MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, and College of Chemistry , Fuzhou University , Fuzhou , 350116 , China
| | - Yanbo Zeng
- College of Biological, Chemical Sciences and Engineering , Jiaxing University , Jiaxing 314001 , People's Republic of China
| | - Lei Li
- College of Biological, Chemical Sciences and Engineering , Jiaxing University , Jiaxing 314001 , People's Republic of China
| | - Bin Qiu
- Institute of Nanomedicine and Nanobiosensing, MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, and College of Chemistry , Fuzhou University , Fuzhou , 350116 , China
| | - Zhenyu Lin
- Institute of Nanomedicine and Nanobiosensing, MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, and College of Chemistry , Fuzhou University , Fuzhou , 350116 , China
| | - Longhua Guo
- Institute of Nanomedicine and Nanobiosensing, MOE Key Laboratory for Analytical Science of Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, and College of Chemistry , Fuzhou University , Fuzhou , 350116 , China
- College of Biological, Chemical Sciences and Engineering , Jiaxing University , Jiaxing 314001 , People's Republic of China
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3
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Rahim S, Rauf A, Rauf S, Shah MR, Malik MI. Enhanced electrochemical response of a modified glassy carbon electrode by poly(2-vinlypyridine- b-methyl methacrylate) conjugated gold nanoparticles for detection of nicotine. RSC Adv 2018; 8:35776-35786. [PMID: 35547912 PMCID: PMC9088209 DOI: 10.1039/c8ra06857g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 10/10/2018] [Indexed: 12/04/2022] Open
Abstract
Poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] were prepared and characterized by UV-Vis, FTIR, AFM, and zetasizer analysis. Investigation of the potential of the synthesized poly(2-vinylpyridine-b-methylmethacrylate) coated gold nanoparticles [P(2VP-MMA)-AuNPs] for detection of nicotine is the main focus of the current study. P(2VP-MMA)-AuNPs were coated on a glassy carbon electrode (GCE) for electrochemical detection of nicotine by cyclic voltammetry. The effect of molar mass of individual P2VP blocks and total molar mass of the block copolymer is evaluated in the context of an enhanced electrochemical response of the modified GCE for its sensing ability of nicotine in both aqueous and organic media. The electrochemical detection of nicotine is significantly enhanced by modification of the GCE with P(2VP-MMA)-AuNPs.
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Affiliation(s)
- Sana Rahim
- H. E. J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences (ICCBS), University of Karachi Karachi 75270 Pakistan
| | - Asma Rauf
- H. E. J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences (ICCBS), University of Karachi Karachi 75270 Pakistan
| | - Saba Rauf
- H. E. J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences (ICCBS), University of Karachi Karachi 75270 Pakistan
| | - Muhammad Raza Shah
- H. E. J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences (ICCBS), University of Karachi Karachi 75270 Pakistan
| | - Muhammad Imran Malik
- H. E. J. Research Institute of Chemistry, International Centre for Chemical and Biological Sciences (ICCBS), University of Karachi Karachi 75270 Pakistan
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4
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Sander LC, Pritchett JS, Daniels YC, Wood LJ, Lang BE, Wise SA, Yen JH, Johnson TL, Walters MJ, Phillips T, Holman MR, Lee GE, Lisko JG, Lane B, Valentin-Blasini L, Watson C. Development of a Cigarette Tobacco Filler Standard Reference Material. Anal Chem 2017; 89:10461-10467. [PMID: 28930436 DOI: 10.1021/acs.analchem.7b02550] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A new tobacco filler Standard Reference Material (SRM) has been issued by the National Institute of Standards and Technology (NIST) in September 2016 with certified and reference mass fraction values for nicotine, N-nitrosonornicotine, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone, and volatiles. The constituents have been determined by multiple analytical methods with measurements at NIST and at the Centers for Disease Control and Prevention, and with confirmatory measurements by commercial laboratories. This effort highlights the development of the first SRM for reduced nicotine and reduced tobacco-specific nitrosamines with certified values for composition.
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Affiliation(s)
- Lane C Sander
- National Institute of Standards and Technology (NIST) , Chemical Sciences Division, 100 Bureau Drive, MS 8392, Gaithersburg, Maryland 20899-8392, United States
| | - Jeanita S Pritchett
- National Institute of Standards and Technology (NIST) , Chemical Sciences Division, 100 Bureau Drive, MS 8392, Gaithersburg, Maryland 20899-8392, United States
| | - Yasmine C Daniels
- National Institute of Standards and Technology (NIST) , Chemical Sciences Division, 100 Bureau Drive, MS 8392, Gaithersburg, Maryland 20899-8392, United States
| | - Laura J Wood
- National Institute of Standards and Technology (NIST) , Chemical Sciences Division, 100 Bureau Drive, MS 8392, Gaithersburg, Maryland 20899-8392, United States
| | - Brian E Lang
- National Institute of Standards and Technology (NIST) , Chemical Sciences Division, 100 Bureau Drive, MS 8392, Gaithersburg, Maryland 20899-8392, United States
| | - Stephen A Wise
- National Institute of Standards and Technology (NIST) , Chemical Sciences Division, 100 Bureau Drive, MS 8392, Gaithersburg, Maryland 20899-8392, United States
| | - James H Yen
- NIST , Statistical Engineering Division, 100 Bureau Drive, MS 8980, Gaithersburg, Maryland 20899-8980, United States
| | - Tricia L Johnson
- Center for Tobacco Products, U.S. Food and Drug Administration , 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, United States
| | - Matthew J Walters
- Center for Tobacco Products, U.S. Food and Drug Administration , 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, United States
| | - Tracy Phillips
- Center for Tobacco Products, U.S. Food and Drug Administration , 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, United States
| | - Matthew R Holman
- Center for Tobacco Products, U.S. Food and Drug Administration , 10903 New Hampshire Avenue, Silver Spring, Maryland 20993, United States
| | - Grace E Lee
- Centers for Disease Control and Prevention , Tobacco Products Laboratory, 4770 Buford Highway, Atlanta, Georgia 30341, United States
| | - Joseph G Lisko
- Centers for Disease Control and Prevention , Tobacco Products Laboratory, 4770 Buford Highway, Atlanta, Georgia 30341, United States
| | - Brian Lane
- Centers for Disease Control and Prevention , Tobacco Products Laboratory, 4770 Buford Highway, Atlanta, Georgia 30341, United States
| | - Liza Valentin-Blasini
- Centers for Disease Control and Prevention , Tobacco Products Laboratory, 4770 Buford Highway, Atlanta, Georgia 30341, United States
| | - Clifford Watson
- Centers for Disease Control and Prevention , Tobacco Products Laboratory, 4770 Buford Highway, Atlanta, Georgia 30341, United States
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5
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Moghbel N, Ryu B, Steadman KJ. A reversed-phase HPLC-UV method developed and validated for simultaneous quantification of six alkaloids from Nicotiana spp. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 997:142-5. [PMID: 26114650 DOI: 10.1016/j.jchromb.2015.06.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2015] [Revised: 06/08/2015] [Accepted: 06/10/2015] [Indexed: 11/23/2022]
Abstract
A reversed-phase HPLC-UV method was developed, optimized, and validated for the separation and quantitation of six target alkaloids from leaves of Nicotiana species (nicotine, nornicotine, anatabine, anabasine, myosmine, and cotinine). A bidentate reversed-phase C18 column was used as stationary phase and an alkaline ammonium formate buffer and acetonitrile as mobile phase. The alkaloids were well separated in a short run time of 13min with mobile phase pH 10.5 and a small gradient of 9-13% acetonitrile, and detected using UV at 260nm. Peak parameters were acceptable for all six closely related alkaloids. The proposed method has enough linearity with correlation coefficient >0.999 within the investigated range for all tested alkaloids. Satisfactory precision was achieved for both intra- and inter-day assay, with RSD less than 2% for all alkaloid standards. Reproducibility was also within the acceptable range of RSD <2%. Limit of detection was 1.6μg/mL for nicotine and below 1μg/mL for all other alkaloids. The limit of quantification was 2.8 and 4.8μg/mL for nornicotine and nicotine respectively, and below 2μg/mL for all other alkaloids. The method was successfully applied for simultaneous analysis of alkaloids in leaves of Nicotiana benthamiana.
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Affiliation(s)
- Nahid Moghbel
- School of Pharmacy, The University of Queensland, Brisbane, Qld 4072, Australia
| | - BoMi Ryu
- School of Pharmacy, The University of Queensland, Brisbane, Qld 4072, Australia
| | - Kathryn J Steadman
- School of Pharmacy, The University of Queensland, Brisbane, Qld 4072, Australia.
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6
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Taujenis L, Olšauskaitė V, Padarauskas A. Determination of nicotine and three minor alkaloids in tobacco by hydrophilic interaction chromatography-tandem mass spectrometry. ACTA CHROMATOGR 2015. [DOI: 10.1556/achrom.27.2015.2.12] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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7
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Kim Y, Kim J. Modification of indium tin oxide with dendrimer-encapsulated nanoparticles to provide enhanced stable electrochemiluminescence of Ru(bpy)3(2+)/tripropylamine while preserving optical transparency of indium tin oxide for sensitive electrochemiluminescence-based analyses. Anal Chem 2014; 86:1654-60. [PMID: 24397739 DOI: 10.1021/ac403415m] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Here, we report highly enhanced stable electrogenerated chemiluminescence (ECL) of Ru(bpy)3(2+) (bpy = 2,2'-bipyridyl) with tripropylamine (TPrA) coreactant on indium tin oxide (ITO) electrodes modified with amine-terminated dendrimers encapsulating catalytic nanoparticles while maintaining optical transparency of ITO and feasibility of the modified ITOs to sensitive ECL-based assays. As model systems, we prepared Pt and Au dendrimer-encapsulated nanoparticles (DENs) using amine-terminated sixth-generation poly(amido amine) dendrimers and subsequently immobilized the DENs onto ITO surfaces via electrooxidative grafting of the terminal amines of dendrimers to the surfaces. The resulting DEN-modified ITOs preserved good optical transparency of ITO and exhibited highly catalyzed electrochemical oxidation of Ru(bpy)3(2+)/TPrA, leading to significantly increased ECL emission. Especially, the Pt DEN-modified ITO electrode provides negligible transmittance drop, i.e., only ∼1.99% over the entire visible region, and exhibited not only much enhanced (i.e., ∼213-fold increase compared to ECL obtained from bare ITO) but also stable ECL emission under consecutive potential scans from 0.00 to 1.10 V for 10 cycles, which allowed ∼329 times more sensitive ECL-based analysis of nicotine using the Pt DEN-modified ITO compared with the use of bare ITO.
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Affiliation(s)
- Yeoju Kim
- Department of Chemistry, Research Institute for Basic Sciences, Kyung Hee University , 1 Hoegi-dong, Seoul 130-701, Republic of Korea
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8
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Šimánek V, Zatloukalová M, Vacek J. Electrochemical Behaviour of Alkaloids: Detection and Interaction with DNA and Proteins. HETEROCYCLES 2014. [DOI: 10.3987/rev-13-sr(s)6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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9
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Lin X, Sun Y, Xu D, Li Y, Liu S, Xie Z. Sensitive capillary electrophoretic profiling of nicotine and nornicotine in mushrooms with amperometric detection. Electrophoresis 2013; 34:2033-40. [DOI: 10.1002/elps.201200527] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 12/03/2012] [Accepted: 01/06/2013] [Indexed: 11/05/2022]
Affiliation(s)
- Xucong Lin
- Institute of Food Safety and Environmental Monitoring; Fuzhou University; Fuzhou; P. R. China
| | - Yingying Sun
- Institute of Food Safety and Environmental Monitoring; Fuzhou University; Fuzhou; P. R. China
| | - Dongjie Xu
- Institute of Food Safety and Environmental Monitoring; Fuzhou University; Fuzhou; P. R. China
| | - Yanping Li
- Institute of Food Safety and Environmental Monitoring; Fuzhou University; Fuzhou; P. R. China
| | - Shaofeng Liu
- Zhengzhou Tobacco Research Institute of CNTC; Zhengzhou; P. R. China
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10
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Badr JM, Bamane FH, El-Shaer NS. APPLICATION OF HIGH PERFORMANCE THIN LAYER CHROMATOGRAPHY FOR DETERMINATION OF NICOTINE IN DIFFERENT BRANDS OF CIGARETTES. J LIQ CHROMATOGR R T 2012. [DOI: 10.1080/10826076.2011.619031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Jihan M. Badr
- a Department of Pharmacognosy, Faculty of Pharmacy , Suez Canal University , Ismailia , Egypt
- b Department of Natural Products and Alternative Medicine, Faculty of Pharmacy , King Abdulaziz University , Jeddah , Kingdom of Saudi Arabia
| | - Faida H. Bamane
- c Department of Biochemistry, Faculty of Medicine , King Abdulaziz University , Jeddah , Kingdom of Saudi Arabia
| | - Nagwa S. El-Shaer
- b Department of Natural Products and Alternative Medicine, Faculty of Pharmacy , King Abdulaziz University , Jeddah , Kingdom of Saudi Arabia
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11
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Paillat L, Périchet C, Lavoine S, Meierhenrich U, Fernandez X. Validated high-performance thin-layer chromatography method for the determination of nicotine in tobacco (Nicotiana tabacumL.) extracts. JPC-J PLANAR CHROMAT 2012. [DOI: 10.1556/jpc.25.2012.1.4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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12
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Freire MG, Teles ARR, Canongia Lopes JN, Rebelo LPN, Marrucho IM, Coutinho JAP. Partition Coefficients of Alkaloids in Biphasic Ionic-Liquid-Aqueous Systems and their Dependence on the Hofmeister Series. SEP SCI TECHNOL 2012. [DOI: 10.1080/01496395.2011.620585] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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13
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Sun J, Du H, You T. Determination of nicotine and its metabolite cotinine in urine and cigarette samples by capillary electrophoresis coupled with electrochemiluminescence. Electrophoresis 2011; 32:2148-54. [PMID: 21792993 DOI: 10.1002/elps.201100075] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2011] [Revised: 05/03/2011] [Accepted: 05/03/2011] [Indexed: 11/11/2022]
Abstract
In this paper, CE coupled with electrochemiluminesence (ECL) detection using a 76-μm Pt disk as working electrode was developed for nicotine (NIC) determination. The major metabolite of NIC is cotinine (COT), which has a similar tertiary amine structure to NIC. However, there is a carbonyl group attached in the structure of COT, which leads to the great decrease in ECL response. In order to improve the ECL response of COT, NaBH(4) was used for carbonyl reduction. After reduction, NIC and COT were separated and detected by CE-ECL. ECL response plotted with NIC concentration was linear between 5.0×10(-7) and 5.0×10(-5) mol/L (81-8100 μg/L), with LOD of 5.0×10(-8) mol/L (8.1 μg/L). The developed CE-ECL method was applied for NIC determination in urine and cigarette samples.
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Affiliation(s)
- Jinying Sun
- State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Changchun, PR China
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14
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Fast and selective extraction of nicotine from human plasma based on magnetic strong cation exchange resin followed by liquid chromatography–tandem mass spectrometry. Anal Bioanal Chem 2011; 400:517-26. [DOI: 10.1007/s00216-011-4799-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 02/09/2011] [Accepted: 02/09/2011] [Indexed: 01/01/2023]
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15
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Scholz R, Matysik FM. A novel approach for the separation of neutral analytes by means of electrochemically assisted injection coupled to capillary electrophoresis-mass spectrometry. Analyst 2011; 136:1562-5. [DOI: 10.1039/c0an00794c] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Matysik FM. Elektrochemische Detektion für miniaturisierte Fließsysteme und Trennverfahren. ACTA ACUST UNITED AC 2010. [DOI: 10.1002/nadc.20000480510] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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17
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Trojanowicz M. Recent developments in electrochemical flow detections—A review. Anal Chim Acta 2009; 653:36-58. [DOI: 10.1016/j.aca.2009.08.040] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2009] [Revised: 08/04/2009] [Accepted: 08/28/2009] [Indexed: 12/17/2022]
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18
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Blasco S, Kortz L, Matysik FM. Comparison of detection performance of UV and electrochemical detection in NACE for a range of different capillary inner diameters. Electrophoresis 2009; 30:3355-60. [DOI: 10.1002/elps.200900324] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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19
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Kodama S, Morikawa A, Nakagomi K, Yamamoto A, Sato A, Suzuki K, Yamashita T, Kemmei T, Taga A. Enantioseparation of nicotine alkaloids in cigarettes by CE using sulfated beta-CD as a chiral selector and a capillary coated with amino groups. Electrophoresis 2009; 30:349-56. [PMID: 19123193 DOI: 10.1002/elps.200800340] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
Nicotine (NC) and its related compounds (cotinine (CN), nornicotine (NN), anatabine (AT) and anabasine (AB)) were simultaneously enantioseparated by CE using a capillary with amino groups and sulfated beta-CD as a chiral selector. The optimum running conditions were found to be 30 mM acetate buffer (pH 5.0) containing 8% sulfated beta-CD with an applied voltage of +15 kV at 30 degrees C using direct detection at 260 nm. Using a capillary coated with amino groups, the EOF migrates toward the positive pole. However, when sulfated beta-CD was added to the BGE, it was found that the EOF migrated toward the negative pole due to ionic adsorption of sulfated beta-CD to amino groups on the capillary inner wall. All the cationic analytes migrated as anions, suggesting that they formed stable anionic complexes with sulfated beta-CD. With this system and a simple pretreatment with mini-cartridges, NC alkaloids in five cigarette samples were enantioseparated. As a result, each of the compounds except for CN was detected. In the case of NC, only (S)-NC was detected (more than 99.9%), but in the case of NN, AT and AB, the ratios of (S)-isomer to total isomers were in the ranges 58-70, 81-85 and 59-65%, respectively. On the other hand, only NC was detected in cigarette smoke and the ratio of (S)- and (R)-NCs was 96:4. The amounts of NC alkaloids in cigarettes suggest that the production of (R)-NC resulted from racemization due to the high temperature/burning of the cigarette.
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Matysik FM, Neusüss C, Pelzing M. Fast capillary electrophoresis coupled with time-of-flight mass spectrometry under separation conditions of high electrical field strengths. Analyst 2008; 133:1764-6. [PMID: 19082081 DOI: 10.1039/b806349d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An experimental approach is presented that enables very fast capillary electrophoretic separations in conjunction with time-of-flight mass spectrometry. Field strengths exceeding 1 kV cm(-1) have been applied for separations of model analytes resulting in migration times on the timescale of seconds.
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21
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Kowalski P, Marszałł M, Olędzka I, Czarnowski W. Comparative Evaluation of CE and HPLC for Determination of Cotinine in Human Urine. Chromatographia 2007. [DOI: 10.1365/s10337-007-0331-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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22
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Chang PL, Lee KH, Hu CC, Chang HT. CE with sequential light-emitting diode-induced fluorescence and electro-chemiluminescence detections for the determination of amino acids and alkaloids. Electrophoresis 2007; 28:1092-9. [PMID: 17330227 DOI: 10.1002/elps.200600546] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
This paper describes the determination of alkaloids and amino acids (AAs) using CE in conjunction with sequential light-emitting diode-induced fluorescence (LEDIF) and electrochemiluminescence (ECL) detections. In the CE-LEDIF-ECL system, the ECL detector was located in the outlet of the capillary, while the LEDIF detector was positioned 12 cm from the outlet. Naphthalene-2,3-dicarboxaldehyde (NDA) was used to form fluorescent AA-NDA derivatives from AAs possessing primary amino groups, while Ru(bpy)(3) (2+) was used to obtain ECL signals for analytes having secondary and tertiary amino groups. In the presence of poly(ethylene oxide), we accomplished the CE-LEDIF-ECL separation of a mixture of 12 AA-NDA derivatives, anabasine, nicotine, and proline within 11 min. This low-cost CE-LEDIF-ECL system allows the analysis of these AA-NDA derivatives and alkaloids at concentrations in the ranges of 49 nM-0.2 microM and 0.66-4.7 microM, respectively. We applied our CE-LEDIF-ECL system to the analysis of a urine sample and also to tobacco extracts. We obtained good qualitative and quantitative results when using this method with these analytes: the RSDs were below 3.0 and 2.8%, respectively. This CE-LEDIF-ECL system provides the advantages of high efficiency, speed, and sensitivity for the analysis of analytes possessing amino groups.
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Affiliation(s)
- Po-Ling Chang
- Department of Chemistry, National Taiwan University, Taipei, Taiwan
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Abstract
This review presents different solvents and electrolytes commonly used as BGEs in NACE for the analysis of pharmaceutical compounds. Most NACE applications carried out since 1998 for the analysis of compounds of pharmaceutical interest are presented in four tables: (i) analysis of drugs and related substances, (ii) analysis of chiral substances, (iii) analysis of phytochemical extracts and (iv) analysis of drugs in biological fluids. These selected examples are used to illustrate the interest in NACE versus conventional aqueous CE.
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Affiliation(s)
- Laurent Geiser
- Laboratory of Analytical Pharmaceutical Chemistry, School of Pharmaceutical Sciences, University of Geneva, University of Lausanne,Geneva, Switzerland
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Matysik FM. Capillary batch injection – A new approach for sample introduction into short-length capillary electrophoresis with electrochemical detection. Electrochem commun 2006. [DOI: 10.1016/j.elecom.2006.04.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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25
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Psurek A, Matysik FM, Scriba GKE. Determination of enkephalin peptides by nonaqueous capillary electrophoresis with electrochemical detection. Electrophoresis 2006; 27:1199-208. [PMID: 16523458 DOI: 10.1002/elps.200500499] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Nonaqueous capillary electrophoresis with electrochemical detection (NACE-ED) was applied to the analysis of enkephalin peptides. The effect of different buffer compositions on the electrophoretic behavior of methionine enkephalin, leucine enkephalin, and [D-Ala2]-leucine enkephalin was studied. Separation of the protonated and the deprotonated peptides was obtained using ACN/methanol-based electrolyte systems. The electrochemical behavior of the enkephalins was studied by the capillary batch injection analysis technique. NACE-ED yielded well-defined signals in the oxidation mode only for the negatively charged analytes. The optimized BGE for the counterelectroosmotic separation consisted of 10 mM ammonium acetate in ACN/methanol (3:1 v/v). Using a platinum microdisk electrode set to an actual potential of +0.65 V detection limits in the submicromolar range were observed which are about one order of magnitude lower compared to UV detection. Problems concerning EOF instability and electrode fouling caused by water and other neutral sample impurities transported by the EOF can be avoided in the EOF-inverted mode using poly(ethylene glycol)-coated capillaries and an actual working electrode potential of +1.0 V. For the quantification of the enkephalins [D-Ala2]leucine enkephalin was used as internal standard. The practical utility for the determination of enkephalins in spiked plasma samples after SPE was demonstrated.
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Affiliation(s)
- Arndt Psurek
- Department of Pharmaceutical Chemistry, School of Pharmacy, University of Jena, Jena, Germany
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26
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Pumera M, Jindrich J, Valásek M, Pecka J. Nonaqueous capillary electrophoretic assays ofp-phenylene-bis-4,4'-(1-aryl-2,6-diphenylpyridinium) molecular wires. Electrophoresis 2005; 26:4465-7. [PMID: 16259016 DOI: 10.1002/elps.200500414] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A nonaqueous CE system for separation and detection of novel electron-dopable molecular wires based on p-phenylene-bis-4,4'-(1-aryl-2,6-diphenylpyridinium) oligomers is described. The method is based on the coupling of CE separation in pure organic solvent, DMF with 50 mM acetic acid, and UV detection at 338 nm. The system offers a rapid measurement in less than 20 min for two priority nanowires and their impurities. Calibration data confirmed linear response for all compounds of interest in the concentration range 0.1-1.0 mg/mL. A highly stable response was observed for repetitive injections (RSD < or = 2.8%, n = 10).
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Affiliation(s)
- Martin Pumera
- Department of Chemistry, Universitat Autonoma de Barcelona, Bellaterra, Barcelona, Spain.
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27
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Guo L, Matysik FM, Gläser P, Engewald W. Determination of hydrazine, monomethylhydrazine, 1,1-dimethylhydrazine, and 1,2-dimethylhydrazine by nonaqueous capillary electrophoresis with amperometric detection. Electrophoresis 2005; 26:3341-8. [PMID: 16097027 DOI: 10.1002/elps.200500188] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The present study is concerned with the application of nonaqueous capillary electrophoresis (NACE) with electrochemical detection (ED) to the separation and quantitative determination of hydrazine (Hy) and its methyl derivatives. The best performance of NACE-ED was found when using 4 mM sodium acetate/10 mM acetic acid/methanol: acetonitrile = 1:2 as the running buffer, with a bare platinum working electrode set at +1.0 V in an end-column amperometric detection cell. The choice and ratio of suitable solvents for the separation and injection media played an essential role for the performance characteristics of the method. The limits of detection for Hy, methylhydrazine, symmetrical dimethylhydrazine, and unsymmetrical dimethylhydrazine were 5, 2, 12, and 1 ng/mL, respectively. This is between one and two orders of magnitude lower than that achieved by previously reported CE-ED methods in aqueous buffer systems in conjunction with various types of chemically modified electrodes. The practical utility of the new NACE-ED methodology is demonstrated in terms of the determination of traces of Hys in spiked environmental samples containing a wide range of explosives and related compounds.
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Affiliation(s)
- Lei Guo
- Institut für Analytische Chemie, Universität Leipzig, Leipzig, Germany
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28
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Che AJ, Zhang JY, Li CH, Chen XF, Hu ZD, Chen XG. Separation and determination of active components in Radix Salviae miltiorrhizae and its medicinal preparations by nonaqueous capillary electrophoresis. J Sep Sci 2004; 27:569-75. [PMID: 15335042 DOI: 10.1002/jssc.200301710] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A nonaqueous capillary electrophoresis (NACE) method was developed for simultaneous assay of three bioactive components (1: cryptotanshinone; 2: tanshinone IIA, and 3: tanshinone I) in Radix Salviae miltiorrhizae and in its herbal preparations for the first time. After optimization of separation conditions, a buffer of 250 mmol L(-1) ammonium acetate containing 30% acetonitrile and 1.0% acetic acid (V:V) in methanol was selected for separating the three analytes, but baseline separation of tanshinon I and tanshinone IIA was not obtained. Therefore second-order derivative electropherograms were applied for resolving overlapping peaks. Regression equations revealed good linear relationships (correlation coefficients 0.9943-0.9991) between peak heights in second-order derivative electropherograms and concentrations of the three analytes. The relative standard deviations (RSD) of the migration times and the peak height of the three constituents were in the range of 0.81 -0.88% and 0.34-1.13% (intra-day), 1.57-1.86% and 3.05-5.52% (inter-day), respectively. The recoveries of three constituents ranged from 90.2 to 108.5%. The results indicated that baseline separation of the analytes was sometimes hard to obtain and second-order derivative electropherograms were applicable for the resolving and analysis of overlapping peaks.
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Affiliation(s)
- An Jia Che
- Department of Chemistry, Lanzhou University, Lanzhou 730000, P.R. China
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29
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Baidoo EEK, Clench MR, Smith RF, Tetler LW. Determination of nicotine and its metabolites in urine by solid-phase extraction and sample stacking capillary electrophoresis-mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 796:303-13. [PMID: 14581070 DOI: 10.1016/j.jchromb.2003.08.016] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The combination of capillary electrophoresis (CE) and mass spectrometry (MS) with solid-phase extraction (SPE) has been used for the identification of nicotine and eight of its metabolites in urine. The recovery of cotinine from cotinine-spiked urine, by C18 SPE, was found to be 98%. Smokers urine (200 ml) was preconcentrated 200-fold via SPE prior to analysis. The sample stacking mode of CE, when compared to capillary zone electrophoresis, was shown to improve peak efficiency by 132-fold. The combination of hydrodynamic and electrokinetic injection was studied with sample stacking/CE/MS. The on-column limits of detection (LOD) of nicotine and cotinine, by this technique, were found to be 0.11 and 2.25 microg/ml, respectively. Hence, LODs of nicotine and cotinine in urine after 200-fold preconcentration were 0.55 and 11.25 ng/ml, respectively.
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Affiliation(s)
- Edward E K Baidoo
- Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB, UK
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30
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Vaher M, Koel M. Separation of polyphenolic compounds extracted from plant matrices using capillary electrophoresis. J Chromatogr A 2003; 990:225-30. [PMID: 12685601 DOI: 10.1016/s0021-9673(02)02013-7] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Phenolic compounds constitute a large group of secondary plant products whose chemical structure may range from quite simple compounds to highly polymerized substances. The polyphenols content have been investigated in the alcoholic extract of the fruits of three different plants: sweet gale, sea buckthorn, hiprose. The trans-resveratrol content we have studied in roots, stems, leaves and flowers of Japanese knotweed grown in Estonia. Plant material was pre-treated in two different ways: by infusing with methanol and by supercritical fluid extraction with carbon dioxide modified with different alcohols. The relationship between variables (pressure, temperature, modifier amount) and yields are examined. The capillary zone electrophoresis methods were developed for the separation of polyphenolic anti-oxidative compounds. Using both water based borate buffer and acetonitrile based non-aqueous media it was possible to get reliable separation of several polyphenolic compounds. Based on that there has been identified such as flavone, trans-resveratrol, catechin, chlorogenic acid, quercetin and myricetin in plant extracts. Changes in the relative concentrations of trans-resveratrol in different parts of the knotweed have been established.
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Affiliation(s)
- Merike Vaher
- Faculty of Chemistry, Department of Sciences, Tallinn Technical University, Akadeemia 15, Tallinn 12618, Estonia.
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31
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Abstract
Nonaqueous capillary electrophoresis (NACE) which makes use of organic solvents in place of conventional aqueous electrophoresis buffers is gaining increasing importance among modern separation techniques. Recently, it has been shown that amperometric detection in conjunction with acetonitrile-based NACE offers an extended accessible potential range and an enhanced long-term stability of the amperometric responses generated at solid electrodes. The present contribution takes advantage of the latter aspect to develop reliable systems for NACE with indirect electrochemical detection (IED). In this context, several compounds such as (ferrocenylmethyl)trimethylammonium perchlorate, tris(1,10-phenanthroline)cobalt(III) perchlorate and bis(1,4,7-triazacyclononane)nickel(II) perchlorate were studied regarding their suitability to act as electroactive buffer additives for IED in NACE. The performance characteristics for the respective buffer systems were evaluated. Tetraalkylammonium perchlorates served as model compounds for the optimization of the NACE-IED system. Target analytes choline and acetylcholine could easily be separated and determined by means of NACE-IED. In the case of a buffer system containing 10(-4) M tris(1,10-phenanthroline)cobalt(III) perchlorate the limits of detection were 2.5 x 10(-7) M and 4.6 x 10(-7) M for choline and acetylcholine, respectively. With the elaborated analytical procedure choline could be determined in pharmaceutical preparations.
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Backofen U, Matysik FM, Lunte CE. Determination of cannabinoids in hair using high-pH* non-aqueous electrolytes and electrochemical detection. Some aspects of sensitivity and selectivity. J Chromatogr A 2002; 942:259-69. [PMID: 11822390 DOI: 10.1016/s0021-9673(01)01348-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Non-aqueous capillary electrophoresis with electrochemical detection (NACE-ED) was applied to the determination of cannabinoids in hair. The effect of different electrolyte compositions on the selectivity of the separation of tetrahydrocannabinol (THC), cannabinol (CBN), cannabidiol (CBD) and tetrahydrocannabinol carboxylic acid (THCA) was studied. Complete electrophoretic resolution was obtained using a strongly basic background electrolyte consisting of 5 mM sodium hydroxide dissolved in acetonitrile-methanol (1:1). Electrochemical detection yielded well defined signals in the oxidation mode. In order to obtain low limits of detection experimental parameters, which determine the sensitivity and the noise level, were optimized. A crucial parameter for sensitive measurements using a wall-tube flow cell as end-column detector is the distance between the capillary outlet and the working electrode. The highest signal-to-noise ratio using a 50 microm I.D. capillary was obtained at a distance of 25 microm. When the capillary outlet was moved away from the working electrode, thus reducing the strength of the separation field present at the working electrode, a large low frequency noise developed. This rise was attributed to disturbances of the hydrodynamic pattern in the flow cell. Analytical aspects such as sensitivity, reproducibility and selectivity were addressed in this work. The precision of NACE-ED regarding migration time and peak height for a sample containing 1 microg/ml THC was 0.4% and 1.1% (RSD), respectively (n=5). The calibration curve was linear for concentrations ranging between 0.1 and 10 microg/ml (r=0.998). The limit of detection for THC was 37 ng/ml, which is almost two orders of magnitude lower when compared with on-column UV detection. The method was evaluated using hair samples containing cannabinoids as sample material.
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Affiliation(s)
- Ulli Backofen
- University of Kansas, Department of Chemistry, Lawrence 66045, USA
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Goto M, Inagaki S, Esaka Y. A handy detection cell for end-column electrochemical detection in capillary electrophoresis. ANAL SCI 2001; 17:1383-7. [PMID: 11783786 DOI: 10.2116/analsci.17.1383] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
A handy and simple detection cell was constructed using a mixing joint for end-column electrochemical detection in capillary electrophoresis (CE). The cell allows for positioning of the working electrode at the end of the separation capillary without the aid of micropositioners. The design facilitates the exchange of electrodes and capillaries without the need to refabricate the entire capillary-electrode setup. The cell can be assembled in a short period of time. Alignment with the joint screw proved to be reproducible for working electrodes of copper and gold. The advantages of reduced time and low cost make the device very attractive for the routine analysis of electroactive species, such as carbohydrates and their derivatives, purine bases and nucleosides, amino acids, and catecholamines etc. by CE with electrochemical detection.
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Affiliation(s)
- M Goto
- Department of Pharmaceutical Analytical Chemistry, Gifu Pharmaceutical University, Japan
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Wright LP, Aucamp JP, Apostolides Z. Analysis of black tea theaflavins by non-aqueous capillary electrophoresis. J Chromatogr A 2001; 919:205-13. [PMID: 11459305 DOI: 10.1016/s0021-9673(01)00762-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
In this study a new capillary electrophoresis (CE) method was developed to quantify the four major theaflavins occurring in black tea. Where aqueous based CE methods showed poor selectivity and considerable band broadening, non-aqueous CE achieved baseline separation of the theaflavins within 10 min. The effects of the organic solvent composition and background electrolyte concentration on the separation selectivity and electrophoretic mobilities were investigated. Our optimized separation solution consisted of acetonitrile-methanol-acetic acid (71:25:4, v/v) and 90 mM ammonium acetate. This method was used to analyze three black tea samples.
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Affiliation(s)
- L P Wright
- Department of Biochemistry, University of Pretoria, South Africa
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36
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Palmer ME, Smith RF, Chambers K, Tetler LW. Separation of nicotine metabolites by capillary zone electrophoresis and capillary zone electrophoresis/mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2001; 15:224-231. [PMID: 11180554 DOI: 10.1002/1097-0231(20010215)15:3<224::aid-rcm213>3.0.co;2-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The use of capillary zone electrophoresis (CZE) and capillary zone electrophoresis/mass spectrometry (CZE/MS) has been demonstrated, in principle, for the separation of nicotine and nicotine metabolites. The buffer system developed for separation and detection by CZE/UV was modified for use in CZE/MS analysis. Several of the metabolites are isobaric and tandem mass spectrometric (MS/MS) techniques have been used to differentiate such analytes.
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Affiliation(s)
- M E Palmer
- Division of Chemistry, Sheffield Hallam University, Howard St., Sheffield S1 1WB, UK
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37
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Abstract
Nonaqueous capillary electrophoresis (NACE) is the application of a conductive electrolyte dissolved in either one organic solvent or a mixture of several organic solvents to carry out zone electrophoresis or related techniques in fused-silica capillaries. A complete review on the fundamentals, the optimization of analytical methods, practical considerations, and applications is given. To explain the differences to CE in aqueous media, a brief summary on solvent properties and molecular interactions in solutions introduces the reader into these fields. The use of additives to tune separation selectivity by means beyond a pure zone-electrophoretic mechanism is discussed in detail for organic media. Special detection techniques providing high potential for NACE are presented. Data on the precision of NACE methods and a list of relevant applications are included. More specialized applications like the determination of physicochemical constants in NACE or the setup of a semipreparative mode are described.
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Affiliation(s)
- F Steiner
- University of the Saarland, Instrumental/Environmental Analysis, Saarbrücken, Germany.
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38
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Abstract
Recent advances in the design and application of electrochemical (EC) detection systems in capillary electrophoresis (CE) are reviewed, with the objective of providing the nonelectrochemist with a state-of-the-art picture of CEEC instrumentation and an overview of the principal analytes for which CEEC is best suited. The detection schemes considered here include those based both on amperometry and on potentiometry as both kinds of EC systems are being actively developed in CE and have the potential for broad application in analysis. Over the three-year period covered by this review, an important direction that CEEC has taken is the construction of more complex electrode systems beginning with the use of multiple EC electrodes and culminating with the adaptation of EC detection to microfabricated "lab-on-a-chip" analysis devices. In addition, CEEC applications have now grown to include a broad variety of inorganic, organic, and biochemical analytes and samples.
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Affiliation(s)
- R P Baldwin
- Department of Chemistry, University of Louisville, KY 40292, USA.
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40
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Abstract
The benefits of non-aqueous capillary electrophoresis have been described in a number of recent publications. The wide selection of organic solvents, with their very different physicochemical properties, broadens our scope to manipulate separation selectivity. The lower currents present in non-aqueous solvents allow the use of high electric field strengths and wide bore capillaries, the latter in turn allowing larger sample load. In many cases detection sensitivity can also be enhanced. The potential of non-aqueous capillary electrophoresis is discussed throughout the paper, and the feasibility of capillary electrophoresis under non-aqueous media is demonstrated with reference to several applications.
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Affiliation(s)
- M L Riekkola
- Department of Chemistry, University of Helsinki, Finland.
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Affiliation(s)
- F M Matysik
- Universität Leipzig, Institut für Analytische Chemie, Linnéstr. 3, D-04103 Leipzig, Germany
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