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Wang Y, Zeng Z, Yang L, Zeng H, Li Y, Pu Q, Zhang M. Three-in-One Detector by 3D Printing: Simultaneous Contactless Conductivity, Ultraviolet Absorbance, and Laser-Induced Fluorescence Measurements for Capillary Electrophoresis. Anal Chem 2023; 95:2146-2151. [PMID: 36642960 DOI: 10.1021/acs.analchem.2c04388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
We describe a 3-in-1 detector for simultaneous contactless conductivity (C4D), ultraviolet absorbance (UV-AD), and laser-induced fluorescence (LIF) measurements on a single detection point for capillary electrophoresis (CE). A key component of the detector was a rectangular detector head that was assembled with four 3D-printed parts. Two parts covering the detector head to function as a Faraday cage were fused deposition modeling printed using an electrically conductive material. The other two parts in between the conductive parts were stereolithography (SLA) printed with high-resolution (50 μm) constructions on the surface. After assembling the two SLA printed parts, several cavities were built with the surface constructions. Two electrodes and a Faraday shield for C4D were cast by injecting molten Wood's metal into the cavities. For UV-AD, a slit (100 μm width) was created by putting together two grooves (50 μm depth) on the surface of the SLA printed parts. A 255 nm UV-LED was used as the light source. The effective path length and stray light for a 50 μm id capillary were 39 μm and 13%, which were superior to those of other reported 3D-printed AD detectors. Confocal LIF detection was conducted by using an objective lens to focus the laser on the capillary via a through-hole. The detector was used to detect model analytes, including inorganic and organic ions, and fluorescein isothiocyanate labeled amino acids in a signal-run CE separation. In detecting fluorescein, LODs were 1.3 μM (C4D), 2.0 μM (UV-AD), and 1 nM (LIF). The calibration ranges covered from 0.01 μM to 500 μM.
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Affiliation(s)
- Yingchun Wang
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi 541004, China
| | - Zihan Zeng
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi 541004, China
| | - Liye Yang
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi 541004, China
| | - Hui Zeng
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi 541004, China
| | - Yan Li
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi 541004, China
| | - Qiaosheng Pu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu 730000, China
| | - Min Zhang
- School of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, Guangxi 541004, China
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Hassanpour-Sabet R, Seyfinejad B, Marzi Khosrowshahi E, Nemati M, Afshar Mogaddam MR, Jouyban A. UiO-66-based metal-organic framework for dispersive solid-phase extraction of vanillylmandelic acid from urine before analysis by capillary electrophoresis. RSC Adv 2022; 12:28728-28737. [PMID: 36320520 PMCID: PMC9549476 DOI: 10.1039/d2ra02916b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 09/03/2022] [Indexed: 11/14/2022] Open
Abstract
Dispersive solid-phase extraction (DSPE) was developed for the extraction of vanillylmandelic acid (VMA) in urine samples prior to capillary electrophoresis with diode array detection (CE-DAD). Extraction of VMA by DSPE was carried out by direct addition of 7.5 mg of synthesized amino-functionalized UiO-66 (Zr) metal-organic framework adsorbent into the 5 mL sample solution (pH 4.0), followed by sonication and centrifugation. The supernatant layer was discarded, then the sedimented adsorbent was eluted using borate buffer (75 mM, pH 10). Effective extraction parameters including the amount of adsorbent, sample pH, adsorption and desorption time, type, volume and pH of eluent, and type of adsorbent dispersion method were systematically investigated. Under the optimized conditions, linearity of the method was from 40 to 2000 μg L-1 with a correlation coefficient over 0.9948. The method detection and quantification limits were 12 and 40 μg L-1, respectively. The relative standard deviations for intra-and inter-day precision were 2.4 and 2.8% (n = 5), respectively. The extraction recovery and enrichment factor values were 90% and 9.0 respectively.
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Affiliation(s)
- Roghayeh Hassanpour-Sabet
- Food and Drug Safety Research Center, Tabriz University of Medical SciencesTabrizIran+98 41 31773333+98 41 33372250
| | - Behruoz Seyfinejad
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical SciencesTabrizIran,Student Research Committee, Tabriz University of Medical SciencesTabrizIran
| | - Elnaz Marzi Khosrowshahi
- Food and Drug Safety Research Center, Tabriz University of Medical SciencesTabrizIran+98 41 31773333+98 41 33372250
| | - Mahboob Nemati
- Food and Drug Safety Research Center, Tabriz University of Medical SciencesTabrizIran+98 41 31773333+98 41 33372250
| | - Mohammad Reza Afshar Mogaddam
- Food and Drug Safety Research Center, Tabriz University of Medical SciencesTabrizIran+98 41 31773333+98 41 33372250,Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical SciencesTabrizIran
| | - Abolghasem Jouyban
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical SciencesTabrizIran,Faculty of Pharmacy, Near East UniversityPO BOX: 99138 NicosiaMersin 10North CyprusTurkey
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[Multimaterial 3D-printed contactless conductivity/laser-induced fluorescence dual-detection cell for capillary electrophoresis]. Se Pu 2021; 39:921-926. [PMID: 34212593 PMCID: PMC9404044 DOI: 10.3724/sp.j.1123.2021.02021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
利用多材料3D打印技术研制了用于毛细管电泳(CE)的二合一检测池,实现了电容耦合非接触电导(C4D)与共聚焦激光诱导荧光(LIF)两种检测方法在毛细管柱上同一位置同时检测。3D打印的检测池采用了导电的复合聚乳酸(PLA)材料制作C4D的屏蔽层,采用普通的绝缘PLA材料支撑C4D金属管电极并隔离屏蔽层。两根金属管电极通过“打印-暂停-打印”的方式嵌入到检测池中,两电极被2 mm厚的导电屏蔽层隔开,在屏蔽层中有一直径为1 mm的圆形通孔用于LIF检测。该检测池与带流通式进样接口的自组装CE系统联用,用于同时检测无机离子和异硫氰酸荧光素(FITC)标记的氨基酸。研究优化了C4D激励信号频率与电泳缓冲液浓度,选用的电泳缓冲溶液为10 mmol/L 3-吗啉丙烷-1-磺酸(MOPS)与10 mmol/L二(2-羟乙基)亚氨基三(羟甲基)甲烷(Bis-Tris)的混合溶液,选用C4D激励频率为77 kHz。二合一检测池应用于内径为25 μm的毛细管时,C 4D对Na+、K+和Li+的检出限分别为2.2、2.0和2.6 μmol/L; LIF对荧光素和FITC的检出限分别为7.6和1.7 nmol/L。两种检测方法的相对标准偏差在0.3%至4.5%之间(n=3),工作曲线的相关系数r2≥0.9904。采用3D打印技术可以在实验室内实现复杂结构的制作,降低了制作的成本,且便于方法的推广和改进。
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Yang L, Pan G, Zhang P, Liu Q, Liu X, Li Y, Liang Y, Zhang M. 3D printed two-in-one on-capillary detector: Combining contactless conductometric and photometric detection for capillary electrophoresis. Anal Chim Acta 2021; 1159:338427. [PMID: 33867034 DOI: 10.1016/j.aca.2021.338427] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 02/23/2021] [Accepted: 03/15/2021] [Indexed: 10/21/2022]
Abstract
In this work, for the first time, a 3D printed two-in-one on-capillary detector, combining contactless conductometric detection (C4D) and photometric detection (PD), is fabricated for capillary electrophoresis (CE). The C4D Faraday shield (FS) is printed using electrically conductive composite polylactic acid (PLA) to minimize the stray capacitance. Non-conductive PLA is also used to print the insulator of FS to prevent the electrical conduction with two stainless steel electrodes. A novel collimator, consisting of two partially aligned pinholes, is printed by conductive material to collimate the light-emitting diode beam. The C4D detection has a signal-to-noise ratio of 1092 ± 2 for 200 μM potassium on a 25 μm id capillary. The PD detection shows excellent linearity with stray light down to 8% and an effective path length at 73% of a 75 μm id capillary. The analytical performance is demonstrated by CE separation and detection of cations. PD shows limits of detection (LODs) of 1.3, 0.9, and 1.7 μM for cobalt, copper and zinc, which are complexed with 4-(2-Pyridylazo) resorcinol, while C4D shows LODs of 1.2, 1.4, 21 and 2.6 μM for potassium, sodium, cobalt and zinc, respectively.
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Affiliation(s)
- Liye Yang
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China
| | - Guangchao Pan
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China
| | - Piwang Zhang
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China
| | - Qiang Liu
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China
| | - Xing Liu
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China
| | - Yan Li
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China
| | - Ying Liang
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China.
| | - Min Zhang
- School of Life and Environmental Sciences, Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin, Guangxi, 541004, China.
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Šesták J, Planeta J, Kahle V. Compact optical detector utilizing light emitting diodes, 50 nL L-shaped silica capillary cell and CCD spectrometer for simultaneous multi-wavelength monitoring of absorbance and fluorescence in microcolumn liquid chromatography. Anal Chim Acta 2020; 1112:80-91. [PMID: 32334686 DOI: 10.1016/j.aca.2020.03.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 03/10/2020] [Accepted: 03/10/2020] [Indexed: 12/21/2022]
Abstract
Optical detection setup utilizing light emitting diodes (LEDs), 50 nL L-shaped silica capillary detection cell (L-cell), and low-cost CCD spectrometer is described in this work. Experimental configuration can be equipped with two different LEDs for absorbance measurement and other two LEDs for fluorescence excitation. This setup is capable of simultaneous multi-wavelength monitoring of absorbance and fluorescence when light produced by the individual LEDs and light emitted by the fluorescent analytes is resolved in the spectrum outputted by the CCD spectrometer. Effective optical path of the 0.25 μm I. D. L-cell is 1 mm. Absorbance baseline noise is 1 mAU due to use of low-cost and relatively noisy CCD spectrometer and LED drivers. Nevertheless, the setup can detect adenosine 5'-monophosphate down to micromolar concentration. Performance of fluorescence monitoring allows detection of 5·10-10 M fluorescein when 23 mW 470 nm LED is used for excitation. The dynamic range of absorbance and fluorescence measurement is 867:1 and 1622:1, respectively. Separation of test mixture (alkylbenzenes and polyaromatic hydrocarbons) demonstrate the effective use of the detector for simultaneous absorbance and fluorescence detection with 0.2 × 150 mm packed capillary column. The benefits of the setup are relative simplicity, compact design and the fact that it can be operated without any optical filters, slits, and extremely precise positioning of the optical elements.
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Affiliation(s)
- Jozef Šesták
- Institute of Analytical Chemistry of the Czech Academy of Sciences, Veveří 97, Brno, Czech Republic.
| | - Josef Planeta
- Institute of Analytical Chemistry of the Czech Academy of Sciences, Veveří 97, Brno, Czech Republic
| | - Vladislav Kahle
- Institute of Analytical Chemistry of the Czech Academy of Sciences, Veveří 97, Brno, Czech Republic
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Zhai H, Yuan K, Yu X, Chen Z, Liu Z, Su Z. A simple and compact fluorescence detection system for capillary electrophoresis and its application to food analysis. Electrophoresis 2015; 36:2509-15. [PMID: 26109527 DOI: 10.1002/elps.201500265] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 06/11/2015] [Accepted: 06/12/2015] [Indexed: 12/20/2022]
Abstract
A novel fluorescence detection system for CE was described and evaluated. Two miniature laser pointers were used as the excitation source. A Y-style optical fiber was used to transmit the excitation light and a four-branch optical fiber was used to collect the fluorescence. The optical fiber and optical filter were imported into a photomultiplier tube without any extra fixing device. A simplified PDMS detection cell was designed with guide channels through which the optical fibers were easily aligned to the detection window of separation capillary. According to different requirements, laser pointers and different filters were selected by simple switching and replacement. The fluorescence from four different directions was collected at the same detecting point. Thus, the sensitivity was enhanced without peak broadening. The fluorescence detection system was simple, compact, low-cost, and highly sensitive, with its functionality demonstrated by the separation and determination of red dyes and fluorescent whitening agents. The detection limit of rhodamine 6G was 7.7 nM (S/N = 3). The system was further applied to determine illegal food dyes. The CE system is potentially eligible for food safety analysis.
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Affiliation(s)
- Haiyun Zhai
- College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China
| | - Kaisong Yuan
- College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China
| | - Xiao Yu
- College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China
| | - Zuanguang Chen
- School of Pharmaceutical Science, Sun Yat-sen University, Guangzhou, P. R. China
| | - Zhenping Liu
- College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China
| | - Zihao Su
- College of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, P. R. China
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de Kort BJ, de Jong GJ, Somsen GW. Native fluorescence detection of biomolecular and pharmaceutical compounds in capillary electrophoresis: Detector designs, performance and applications: A review. Anal Chim Acta 2013; 766:13-33. [DOI: 10.1016/j.aca.2012.12.006] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Revised: 12/01/2012] [Accepted: 12/03/2012] [Indexed: 01/05/2023]
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Monteleone M, Naccarato A, Sindona G, Tagarelli A. A reliable and simple method for the assay of neuroendocrine tumor markers in human urine by solid-phase microextraction-gas chromatography-triple quadrupole mass spectrometry. Anal Chim Acta 2012; 759:66-73. [PMID: 23260678 DOI: 10.1016/j.aca.2012.11.017] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2012] [Revised: 11/06/2012] [Accepted: 11/10/2012] [Indexed: 10/27/2022]
Abstract
Homovanillic acid (HVA), vanylmandelic acid (VMA), and 5-hydroxyindoleacetic acid (5-HIAA) are the metabolites of some catecholamines such as epinephrine, nor-epinephrine, dopamine and serotonin and their quantification is used in the diagnosis and management of patients with neurocrine tumors. A novel approach in the assay of these biomarkers in human urine samples by solid phase microextraction (SPME) combined with gas chromatography-triple quadrupole mass spectrometry (GC-QqQ-MS) is presented. A preliminary derivatization with ethyl chloroformate/ethanol was used and the corresponding derivatives were then extracted by SPME in immersion mode. The performance of five SPME fibers and three chloroformates were evaluated in univariate mode and the best results were obtained using the polyacrylate fiber and ethyl chloroformate. The variables affecting the efficiency of SPME analysis were optimized by the multivariate approach of "Experimental design" and, in particular, a central composite design (CCD) was applied. The optimum working conditions in terms of response values were achieved by performing analysis at room temperature with addition of NaCl (9.5%) and with an extraction time of 25.8 min. Identification and quantification of analytes were carried out by using a gas chromatography-triple quadrupole mass spectrometry (GC-QqQ MS) system in multiple reaction monitoring (MRM) acquisition. An evaluation of all analytical parameters shows that the proposed method provides satisfactory results. Very good linearities were, in fact, achieved in the tested calibration ranges with correlation coefficient values >0.99 for all the analytes and accuracies and RSDs calculated for between-run and tested at concentrations of 1, 10, and 80 mg L(-1) were ranging from 91.3% to 106.6%, and from 0.5 to 8.9%, respectively. Moreover, the LOD values obtained can be considered very satisfactory (1.3, 0.046 and 24.3 μg L(-1) for HVA, VMA and 5-HIAA, respectively). The developed protocol represents, therefore, a simple, rapid and selective tool for assaying these acidic biomarkers in urine samples for neuroendocrine cancer diagnosis.
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Affiliation(s)
- Marcello Monteleone
- Dipartimento di Chimica, Università della Calabria, Via Pietro Bucci Cubo 12/C, I-87030 Arcavacata di Rende (CS), Italy
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Bioanalytical applications of capillary electrophoresis with laser-induced native fluorescence detection. Bioanalysis 2010; 2:1641-53. [DOI: 10.4155/bio.10.72] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
In this article we describe recent developments and applications of capillary electrophoresis (CE) coupled with laser-induced native fluorescence (LINF) detection in the analysis of biological, pharmaceutical and environmental samples. Compared with traditional UV absorbance detection used in CE, the LINF technique can greatly improve the concentration sensitivity of CE without the need for derivatization; the only requirement being that the analyte must have native fluorescence. Instrumentation and laser sources used in CE–LINF are summarized and specific applications of CE–LINF to small-biomolecule analysis, profiling of human biofluids, detection of native fluorescent peptides and proteins, single-cell analysis and the use of online sample preconcentration methods are also reviewed in detail.
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Zhou L, Glennon JD, Luong JHT. Electrophoretic Analysis of Biomarkers using Capillary Modification with Gold Nanoparticles Embedded in a Polycation and Boron Doped Diamond Electrode. Anal Chem 2010; 82:6895-903. [DOI: 10.1021/ac101105q] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lin Zhou
- Innovative Chromatography Group, Irish Separation Science Cluster (ISSC), Department of Chemistry & the ABCRF, University College Cork, Cork, Ireland and Biotechnology Research Institute, National Research Council Canada, Montreal, Quebec, Canada H4P 2R2
| | - Jeremy D. Glennon
- Innovative Chromatography Group, Irish Separation Science Cluster (ISSC), Department of Chemistry & the ABCRF, University College Cork, Cork, Ireland and Biotechnology Research Institute, National Research Council Canada, Montreal, Quebec, Canada H4P 2R2
| | - John H. T. Luong
- Innovative Chromatography Group, Irish Separation Science Cluster (ISSC), Department of Chemistry & the ABCRF, University College Cork, Cork, Ireland and Biotechnology Research Institute, National Research Council Canada, Montreal, Quebec, Canada H4P 2R2
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Ryvolová M, Preisler J, Foret F, Hauser PC, Krásenský P, Paull B, Macka M. Combined Contactless Conductometric, Photometric, and Fluorimetric Single Point Detector for Capillary Separation Methods. Anal Chem 2009; 82:129-35. [DOI: 10.1021/ac902376v] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Markéta Ryvolová
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Jan Preisler
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - František Foret
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Peter C. Hauser
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Pavel Krásenský
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Brett Paull
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
| | - Mirek Macka
- Irish Separation Science Cluster and National Centre for Sensor Research, Dublin City University, Dublin, Ireland, Department of Chemistry and Department of Experimental Biology, Faculty of Science, Masaryk University, Kotlářská 2, 61137 Brno, Czech Republic, Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 60200 Brno, Czech Republic, and Department of Chemistry, University of Basel, 4056 Basel, Switzerland
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Tsimachidis D, Česla P, Hájek T, Theodoridis G, Jandera P. Capillary electrophoretic chiral separation of Cinchona
alkaloids using a cyclodextrin selector. J Sep Sci 2008; 31:1130-6. [DOI: 10.1002/jssc.200700494] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Sádecká J, Netriová J. Determination of Naproxen and its Metabolite, 6‐O‐Desmethylnaproxen, in Human Urine by Capillary Isotachophoresis. J LIQ CHROMATOGR R T 2007. [DOI: 10.1080/10826070500271881] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Jana Sádecká
- a Department of Analytical Chemistry , Faculty of Chemical and Food Technology , Bratislava, Slovakia
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Phillips TM, Wellner EF. Measurement of naproxen in human plasma by chip-based immunoaffinity capillary electrophoresis. Biomed Chromatogr 2006; 20:662-7. [PMID: 16779772 DOI: 10.1002/bmc.673] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
An electrokinetic immunoassay performed in a chip-based capillary electrophoresis system is described for the rapid measurement of naproxen in human plasma. The system employs a fluorescently labeled antibody to capture and detect the analyte of interest within a 5 min total assay time with an LOD of 0.025 microg/mL and a saturation level of 450 microg/mL. The system compared well with a conventional HPLC technique but was found to be much faster. Application of the electrokinetic assay to the study of patients with allergy to naproxen demonstrated increased concentrations of the drug extending past the predicted elimination half-life. The portability of the system and its ability to process up to 18 samples per hour makes it suitable for use in emergency room situations.
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Affiliation(s)
- Terry M Phillips
- Ultramicro Analytical Immunochemistry Resource, Division of Bioengineering and Physical Science, Office of Research Services, National Institutes of Health, Bethesda, MD 20892, USA.
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Macià A, Borrull F, Calull M, Aguilar C. Different sample stacking strategies to analyse some nonsteroidal anti-inflammatory drugs by micellar electrokinetic capillary chromatography in mineral waters. J Chromatogr A 2006; 1117:234-45. [PMID: 16600264 DOI: 10.1016/j.chroma.2006.03.076] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2006] [Revised: 03/20/2006] [Accepted: 03/22/2006] [Indexed: 11/22/2022]
Abstract
Three on-column preconcentration techniques were compared to analyse a group of nonsteroidal anti-inflammatory drugs (NSAIDs) using micellar electrokinetic capillary chromatography (MEKC) under pH-suppressed electroosmotic flow (EOF) in water samples. The analysed drugs were ibuprofen, fenoprofen, naproxen, ketoprofen, and diclofenac sodium. The micellar background electrolyte (BGE) solution was formed by 75 mM sodium dodecyl sulfate (SDS), 40% (v/v) acetonitrile, and 25 mM sodium phosphate at pH 2.5. When this BGE solution was used the applied voltage was reversed, -10 kV, and the drugs were separated within 20 min. The on-column preconcentration modes, characterised all of them for the sample matrix removal out of the capillary by itself under a reverse potential at the same time as the EOF was reduced, were stacking with reverse migrating micelles (SRMM), stacking with reverse migrating micelles-anion selective exhaustive injection (SRMM-ASEI), and field-enhanced sample injection with reverse migrating micelles (FESI-RMM). The sensitivity was improved up to 154-, 263-, and 63-fold, respectively when it was calculated through the peaks height. The optimised methods were validated with spiked mineral water by combining off-line solid-phase extraction (SPE) and the proposed on-line sample stacking strategies. The detection limits (LODs) of NSAIDs in mineral water were at ng/L levels.
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Affiliation(s)
- Alba Macià
- Department of Analytical Chemistry and Organic Chemistry, University Rovira i Virgili, C/Marcel.li Domingo s/n, 43007 Tarragona, Spain
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16
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Hsieh MM, Chang HT. Impact of halides on the simultaneous separation of aromatic amines and their acidic metabolites by capillary electrophoresis with laser-induced native fluorescence detection under acidic conditions. J Chromatogr A 2006; 1102:302-8. [PMID: 16325830 DOI: 10.1016/j.chroma.2005.11.016] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2005] [Revised: 10/28/2005] [Accepted: 11/01/2005] [Indexed: 11/15/2022]
Abstract
This paper describes a simple, sensitive, efficient, and rapid method for simultaneous analysis of biologically active amines and acids by capillary electrophoresis in conjunction with laser-induced native fluorescence detection (CE-LINF) using a diode pumped solid state nanolaser at 266 nm. In order to optimize resolution of the amines that were prepared in 10.0 mM formate-Tris (FT) solutions, 10.0 mM FT solutions with and without containing halides were used to fill the capillary and reservoirs, respectively. The electrophoretic mobilities of tryptamine (TA) and serotonin (5-HT) at pH 4.0 decrease with the increase in halide concentration (0-10.0 mM). Taken together with a great effect of iodide than other halides, we suggest that the formation of ion pairs is a main contributor for altering the migration of the amines. In order to simultaneously analyze the amines and their metabolites (acids) at low pH, a high bulk EOF is required. The analysis of 10 anlytes including amines and acids was completed within 12 min by CE-LINF using a capillary treated with 0.5M NaOH and then filled with 10.0 mM FT solutions (pH 4.0) containing 10.0 mM KCl prior to analysis. The limits of detection for TA and 5-hydroxyindole-3-acetic acid (5-HIAA) are 0.12 and 6.0 nM, respectively. The present method has been further validated by analyzing urine samples, with an RSD less than 3.1% (migration times) and 3.9% (concentration).
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Affiliation(s)
- Ming-Mu Hsieh
- Department of Applied Chemistry, Fooyin University, 151 Chin-Hsueh Road, Ta-Liao Hsiang, 831 Kaohsiung Hsien, Taiwan.
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17
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Baena B, Cifuentes A, Barbas C. Analysis of carboxylic acids in biological fluids by capillary electrophoresis. Electrophoresis 2005; 26:2622-36. [PMID: 15934051 DOI: 10.1002/elps.200410329] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This review article addresses the different capillary electrophoretic methods that are being used for the study of both short-chain organic acids (including anionic catecholamine metabolites) and fatty acids in biological samples. This work intends to provide an updated overview (including works published until November 2004) on the recent methodological developments and applications of such procedures together with their main advantages and drawbacks. Moreover, the usefulness of CE analysis of organic acids to study and/or monitor different diseases such as diabetes, new-borns diseases or metabolism disorders is examined. The use of microchip devices and CE-MS couplings for organic acid analysis is also discussed.
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Affiliation(s)
- Beatriz Baena
- Sección Química Analítica, Fac. CC. Experimentales y de la Salud, Universidad San Pablo-CEU, Madrid, Spain
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18
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Iadarola P, Cetta G, Luisetti M, Annovazzi L, Casado B, Baraniuk J, Zanone C, Viglio S. Micellar electrokinetic chromatographic and capillary zone electrophoretic methods for screening urinary biomarkers of human disorders: a critical review of the state-of-the-art. Electrophoresis 2005; 26:752-766. [PMID: 15669008 DOI: 10.1002/elps.200410195] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Human urine plays a central role in clinical diagnostic being one of the most-frequently used body fluid for detection of biological markers. Samples from patients with different diseases display patterns of biomarkers that differ significantly from those obtained from healthy subjects. The availability of fast, reproducible, and easy-to-apply analytical techniques that would allow identification of a large number of these analytes is thus highly desiderable since they may provide detailed information about the progression of a pathological process. From among the variety of methods so far applied for the determination of urinary metabolites, capillary electrophoresis, both in the capillary zone electrophoresis (CZE) and micellar electrokinetic chromatography (MEKC) modes, represents a robust and reliable analytical tool widely used in this area. The aim of the present article is to focus the interest of the reader on recent applications of MEKC and CZE in the field of urinary biomarkers and to discuss advantages and/or limitations of each mode.
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Affiliation(s)
- Paolo Iadarola
- Dipartimento di Biochimica A.Castellani, Università di Pavia, Pavia, Italy.
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19
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Sirén H, Mielonen M, Herlevi M. Capillary electrophoresis in the determination of anionic catecholamine metabolites from patients’ urine. J Chromatogr A 2004; 1032:289-97. [PMID: 15065807 DOI: 10.1016/j.chroma.2003.12.034] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A micellar electrokinetic capillary chromatographic method for determining anionic catecholamine metabolites from patient urine samples was established. The optimum electrolyte solution (pH 10.6) was made of tetraborate and sodium dodecyl sulphate into water. Furthermore, studies were focused to optimize solid-phase extraction clean-up steps to concentrate patient urine samples for identification of catecholamines with UV detection. The water-micelle distribution coefficients (octanol-water partition coefficient, log Pow) for the analytes were determined by conductometric titration. High plate numbers (120,000-200,000/40 cm detection window) and small diffusion coefficients (2.00-3.50 x 10(-6) cm(-2) s(-1)) resulted in high resolution and symmetry of the analyte zones. The standard deviations of the migration times and the peak heights were less than 3 and 7%, respectively. The octanol-water coefficients increased in the order of decreased pKa1 value of the analytes, why separation between structurally related vanillinic mandelic acids could be obtained. Limits of detection and quantification were around 0.05 and 0.1 microg/ml, respectively, except for dopamine. The concentrations of the catecholamine metabolites in the studied patient urines varied from 0.186 to 76.4 microg/ml. The results showed evidences of serious diseases among the patients.
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Affiliation(s)
- Heli Sirén
- Department of Chemistry, University of Helsinki, PO Box 55, FIN-00014 Helsinki, Finland.
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20
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Chapter 14 Chromatography of amino acids and peptides. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/s0301-4770(04)80027-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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21
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Galli V, García A, Saavedra L, Barbas C. Capillary electrophoresis for short-chain organic acids and inorganic anions in different samples. Electrophoresis 2003; 24:1951-1981. [PMID: 12858368 DOI: 10.1002/elps.200305473] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This review article is a comprehensive survey of capillary electrophoresis methods developed for the measurement of short-chain organic acids and inorganic anions in a wide variety of matrices, such as food and beverages, environmental, industry, and other applications, as well as clinical applications in body fluids such as urine, plasma or cerebrospinal fluid. Details of sample pretreatment and of electrophoretic conditions have been collected in tables, arranged by the type of matrix. Strategies employed for method development for the analysis of these compounds by capillary electrophoresis in real samples are discussed.
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Affiliation(s)
- Verónica Galli
- Facultad de CC. Experimentales y dela Salud, Urbanización Montepríncipe, E-28668 Boadilla del Monte (Madrid), Spain
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22
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Damiani PC, Borraccetti MD, Olivieri AC. Direct and simultaneous spectrofluorometric determination of naproxen and salicylate in human serum assisted by chemometric analysis. Anal Chim Acta 2002. [DOI: 10.1016/s0003-2670(02)00925-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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23
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Li X, Jin W, Weng Q. Separation and determination of homovanillic acid and vanillylmandelic acid by capillary electrophoresis with electrochemical detection. Anal Chim Acta 2002. [DOI: 10.1016/s0003-2670(02)00241-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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24
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Bergquist J, Sciubisz A, Kaczor A, Silberring J. Catecholamines and methods for their identification and quantitation in biological tissues and fluids. J Neurosci Methods 2002; 113:1-13. [PMID: 11741716 DOI: 10.1016/s0165-0270(01)00502-7] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Catecholamines act via dopaminergic-, and adrenergic receptors, and are involved in a variety of regulatory systems. They take part in regulation of the response to stress, psychomotor activity, emotional processes, learning, sleep and memory. Due to many catecholaminergic pathways, and a wide range of functions they are involved in, both in the central nervous system and in periphery, a development of the reliable techniques for their extraction and quantitation is essential. This paper presents an overview of the currently applied methodologies for catecholamines detection and identification in various biological samples.
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Affiliation(s)
- Jonas Bergquist
- Department of Psychiatry and Neurochemistry, Institute of Clinical Neuroscience, Göteborg University, Sahlgrenska University Hospital, Mölndal, Sweden
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25
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Hefnawy MM. Micellar electrokinetic capillary chromatography determination of +S and -R arotinolol in serum using UV detection and solid phase extraction. Chirality 2002; 14:67-71. [PMID: 11748803 DOI: 10.1002/chir.888] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A method for the simultaneous determination of +S and -R arotinolol in serum by micellar electrokinetic capillary chromatography is described. Stereoselective resolution of the arotinolol enantiomers was achieved using 5 mM sodium taurocholate in 10 mM sodium dihydrogen phosphate buffer of pH 2.5. A 72-cm uncoated fused-silica capillary at a constant voltage of 15 kV was used for the analysis. The analytes of interest were extracted from serum using solid phase extraction. An octadecyl cartridge gave good recoveries in excess of 87% for both +S and -R arotinolol without any interference. The calibration curves were linear over the range of 50-500 ng ml(-1) with +S propranolol as the internal standard and the coefficient of determination was greater than 0.999 (n = 3). The limit of quantitation was 50 ng ml(-1) for each enantiomer and the detection limit using 1 ml serum and a UV detection set et 220 nm was 25 ng ml(-1) (S/N = 2). Precision and accuracy of the method were in the range 0.8-2.7% and 1.2-6.4%, respectively, for +S arotinolol and 1.1-3.9% and 2.2-6.5%, respectively, for -R arotinolol.
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Affiliation(s)
- Mohammed M Hefnawy
- Department of Analytical Chemistry, Faculty of Pharmacy, University of Mansoura, Mansoura, 35516, Egypt
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26
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Lemos NP, Bortolotti F, Manetto G, Anderson RA, Cittadini F, Tagliaro F. Capillary electrophoresis: a new tool in forensic medicine and science. Sci Justice 2001; 41:203-10. [PMID: 11515169 DOI: 10.1016/s1355-0306(01)71892-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- N P Lemos
- Forensic Science Unit, South Bank University, 103 Borough Road, London SE1 0AA, United Kingdom
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27
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Glatz Z, Nováková S, Sterbová H. Analysis of thiocyanate in biological fluids by capillary zone electrophoresis. J Chromatogr A 2001; 916:273-7. [PMID: 11382301 DOI: 10.1016/s0021-9673(00)01238-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A new sensitive and simple method has been developed for the determination of thiocyanate in human serum, urine and saliva. The determinations were performed in a fused-silica capillary [64.5 cm (56 cm effective length) x 75 microm] using 0.1 M beta-alanine-HCl (pH 3.50) as a background electrolyte, separation voltage 18 kV (negative polarity), temperature of capillary 25 degrees C and direct detection at 200 nm. Serum samples were 10-times diluted with deionised water and deproteinised with acetonitrile in the ratio 1:2. Urine and saliva samples need only 20-fold dilution with deionised water. The proposed method was successfully applied to the determination of thiocyanate in various human serum, saliva and urine samples.
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Affiliation(s)
- Z Glatz
- Department of Biochemistry, Faculty of Science, Masaryk University, Brno, Czech Republic.
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28
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Zaugg S, Zhang X, Sweedler J, Thormann W. Determination of salicylate, gentisic acid and salicyluric acid in human urine by capillary electrophoresis with laser-induced fluorescence detection. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 2001; 752:17-31. [PMID: 11254191 DOI: 10.1016/s0378-4347(00)00507-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acetylsalicylic acid (Aspirin) is rapidly metabolized to salicylic acid (salicylate) and other compounds, including gentisic acid and salicyluric acid. Monitoring of salicylate and its metabolites is of toxicological, pharmacological and biomedical interest. Three capillary electrophoresis (CE) methods featuring alkaline aqueous buffers, laser-induced fluorescence (LIF) detection and no solute extraction or derivatization have been explored. A competitive binding, electrokinetic capillary-based immunoassay is developed that recognizes the presence of salicylate and gentisic acid in urine. Differentiation of the two compounds, however, is problematic. With appropriate ultraviolet excitation, many salicylate-related compounds are fluorescent so that CE with direct urine injection and LIF detection permits the determination of salicylate, gentisic acid and salicyluric acid. Using a HeCd laser with 325 nm produces interference-free monitoring of all three compounds. Using 257 nm excitation from a frequency doubled Ar ion laser, native fluorescence of an endogenous urinary compound that co-migrates with gentisic acid is observed. With wavelength-resolved fluorescence detection, however, the two substances are distinguished. Furthermore, this technique, with comparison to literature data, permits the putative assignment of several peaks to other salicylate metabolites, namely glucuronide conjugates of salicylate and salicyluric acid. All three CE-LIF techniques have been applied to toxicological patient urines and urines collected after ingestion of 500 mg acetylsalicylic acid. CE results compare favorably with those obtained by a commercial fluorescence polarization immunoassay and by a conventional photometric assay.
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Affiliation(s)
- S Zaugg
- Department of Clinical Pharmacology, University of Bern, Switzerland
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29
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Zaugg S, Thormann W. Capillary electrophoretic separation, immunochemical recognition and analysis of the diastereomers quinine and quinidine and two quinidine metabolites in body fluids. J Pharm Biomed Anal 2001; 24:785-99. [PMID: 11248471 DOI: 10.1016/s0731-7085(00)00546-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The capillary electrophoretic separation and immunochemical recognition of the two naturally fluorescing, cationic diastereomers quinine (QN) and quinidine (QD), their hydroderivatives and two major QD metabolites (3-hydroxyquinidine and quinidine-N-oxide) was investigated. Plain aqueous phosphate buffers and an alkaline buffer containing dodecyl sulfate micelles are shown to be incapable of resolving the two diastereomers. However, incorporation of an additional chemical equilibrium (with beta-cyclodextrin) in the case of capillary zone electrophoresis (CZE) and the presence of a small amount of an organic solvent as buffer modifier (2-propanol) in dodecyl sulfate based micellar electrokinetic capillary chromatography (MECC), were found to provide separation media which lead to complete resolution of QN, QD and the other compounds of interest. Furthermore, for MECC- and CZE-based immunoassay formats, a commercially available antibody against QD was found to be a perfect discriminator between QD and QN. It was determined to recognize QD and the two QD metabolites (cross reactivity of 20--30%) but not QN. MECC and CZE with laser induced fluorescence (LIF) detection are shown to be suitable to determine QD and metabolites in urine and plasma (quinidine-N-oxide only) collected after single dose intake of 50 mg QD sulfate and of QN in urine, saliva and serum samples that were collected after self-administration of 0.5 l of quinine water (25 mg of QN). With direct injection of a body fluid, MECC with LIF was found to provide 10 ng/ml detection limits for QD and QN. This ppb sensitivity is comparable to that obtained in HPLC assays that are based upon drug extraction. Furthermore, MECC and CZE assays with UV detection are shown to provide the ppm sensitivity required for therapeutic drug monitoring and clinical toxicology of QD and QN.
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Affiliation(s)
- S Zaugg
- Department of Clinical Pharmacology, University of Bern, Murtenstrasse 35, CH-3010 Bern, Switzerland
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30
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García A, Heinänen M, Jiménez LM, Barbas C. Direct measurement of homovanillic, vanillylmandelic and 5-hydroxyindoleacetic acids in urine by capillary electrophoresis. J Chromatogr A 2000; 871:341-50. [PMID: 10735314 DOI: 10.1016/s0021-9673(99)00994-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Separation conditions in CE, with a neutral coated capillary and reversed polarity, have been optimised to make direct measurement of vanillylmandelic acid, homovanillic acid and 5-hydroxyindoleacetic acid possible in urine samples without pre-treatment. The method developed has been validated, presenting adequate parameters for linearity, accuracy and precision. Detection limits range from 0.03 to 2.5 microM. Finally the method has been applied to urine samples taken from patients, both adults and children, in hospital. Some of them were also measured by immunoassay and HPLC-electrochemical detection and results have been compared.
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Affiliation(s)
- A García
- Facultad de CC Experimentales y Técnicas, Universidad San Pablo-CEU Urbanización Montepríncipe, Madrid, Spain
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31
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Boone CM, Waterval JC, Lingeman H, Ensing K, Underberg WJ. Capillary electrophoresis as a versatile tool for the bioanalysis of drugs--a review. J Pharm Biomed Anal 1999; 20:831-63. [PMID: 10746954 DOI: 10.1016/s0731-7085(99)00088-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
This review article presents an overview of current research on the use of capillary electrophoretic techniques for the analysis of drugs in biological matrices. The principles of capillary electrophoresis and its various separation and detection modes are briefly discussed. Sample pretreatment methods which have been used for clean-up and concentration are discussed. Finally, an extensive overview of bioanalytical applications is presented. The bioanalyses of more than 200 drugs have been summarised, including the applied sample pretreatment methods and the achieved detection limits.
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Affiliation(s)
- C M Boone
- Department of Analytical Chemistry and Toxicology, University Center for Pharmacy, Groningen, The Netherlands.
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32
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Affiliation(s)
- D Perrett
- Department of Medicine, St Bartholomew's, London, UK
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33
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Abstract
Therapeutic drug monitoring is commonly used in both the ambulatory and hospital patient care settings. Routine measurement of concentrations of therapeutic agents in biological fluids is critical for certain drugs to maintain therapeutic benefit with minimizing drug-associated toxicities. Many analytical laboratory techniques are currently available to measure drug concentrations in biological samples. Recently there has been an increased interest in the use of capillary electrophoresis (CE) for measuring concentrations of therapeutic drugs in patient samples. However, while there are numerous reports of CE being used to measure drug concentrations in solution and pharmaceutical dosage forms, there are relatively few reports of the use of CE for measuring therapeutic agents in patient samples. The purpose of this paper is to provide an overview of methods currently used to measure therapeutic drugs in patient samples along with possible future trends for the use of CE in therapeutic drug monitoring.
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Affiliation(s)
- L J Brunner
- College of Pharmacy, The University of Texas at Austin, 78712-1074, USA.
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34
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Wätzig H, Degenhardt M, Kunkel A. Strategies for capillary electrophoresis: method development and validation for pharmaceutical and biological applications. Electrophoresis 1998; 19:2695-752. [PMID: 9870372 DOI: 10.1002/elps.1150191603] [Citation(s) in RCA: 157] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
This review is in support of the development of selective, reproducible and validated capillary electrophoretis (CE) methods. Focusing on pharmaceutical and biological applications, the successful use of CE is demonstrated by more than 800 references, mainly from 1994 until 1998. Approximately 80 recent reviews have been catalogued. These articles sum up the existing strategies for method development in CE, especially in the search for generally accepted concepts, but also looking for new, promising reagents and ideas. General strategies for method development were derived not only with regard to selectivity and efficiency, but also with regard to precision, short analysis time, limit of detection, sample pretreatment requirements and validation. Standard buffer recipes, surfactants used in micellar electrokinetic capillary chromatography (MEKC), chiral selectors, useful buffer additives, polymeric separation media, electroosmotic flow (EOF) modifiers, dynamic and permanent coatings, actions to deal with complex matrices and aspects of validation are collected in 20 tables. Detailed schemes for the development of MEKC methods and chiral separations, for optimizing separation efficiency, means of troubleshooting, and other important information for key decisions during method development are given in 19 diagrams. Method development for peptide and protein separations, possibilities to influence the EOF and how to stabilize it, as well as indirect detection are considered in special sections.
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Affiliation(s)
- H Wätzig
- Institut für Pharmazie und Lebensmittelchemie, Würzburg, Germany.
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35
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Kitagishi K, Shintani H. Analysis of compounds containing carboxyl groups in biological fluids by capillary electrophoresis. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 717:327-39. [PMID: 9832253 DOI: 10.1016/s0378-4347(98)00290-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Capillary electrophoresis (CE) is one of the suitable separation techniques used to analyze drugs or metabolites in complicated sample matrices such as plasma, serum and urine. It sometimes requires only a simple process of sample pretreatment, deproteinization, dilution or extraction for biological fluids, otherwise no pretreatment is necessary. Various metabolic disorders concerning the compounds which possess carboxyl groups such as organic acids have been monitored by CE. Drug metabolism in the body can be monitored by the same technique. Recent publications suggest the feasibility of an automated system for diagnosis based on CE technique.
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Affiliation(s)
- K Kitagishi
- Otsuka Electronics Co., Hirakata, Osaka, Japan
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36
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Heo YJ, Lee KJ. Application of micellar electrokinetic capillary chromatography for the determination of benzoic acid and its esters in liquid formula medicines as preservatives. J Pharm Biomed Anal 1998; 17:1371-9. [PMID: 9800656 DOI: 10.1016/s0731-7085(98)00023-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We described a method for the simultaneous determination of preservatives including benzoic acid, methyl-, ethyl- and propyl-benzoate by micellar electrokinetic capillary chromatography (MECC). The factors affecting the reproducibility in the quantitative analysis of pharmaceuticals by MECC were investigated by varying the running buffer and washing condition in-between runs. Preservatives in liquid formula medicines have been determined by optimum MECC condition using p-hydroxy benzoic acid as an internal standard. The reproducibility of this method was acceptable as a validate method for the quality control of pharmaceuticals (RSD < 2%). Routine quantitative analysis of pharmaceuticals using MECC could be possible with well characterized reproducible procedure.
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Affiliation(s)
- Y J Heo
- College of Pharmacy, Ewha Womans University, Seoul, South Korea
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37
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Paquette DM, Sing R, Banks PR, Waldron KC. Capillary electrophoresis with laser-induced native fluorescence detection for profiling body fluids. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1998; 714:47-57. [PMID: 9746234 DOI: 10.1016/s0378-4347(98)00118-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Laser-induced native fluorescence detection with a KrF excimer laser (lambda=248 nm) was used to investigate the capillary electrophoretic (CE) profiles of human urine, saliva and serum without the need for sample derivatization. All separations were carried out in sodium phosphate and/or sodium tetraborate buffers at alkaline pH in a 50-microm I.D. capillary. Sodium dodecyl sulfate was added to the buffer for micellar electrokinetic chromatography (MEKC) analysis of human urine. Although inherently a pulsed source, the KrF excimer laser was operated at a high pulse repetition rate of 553, 1001 or 2009 Hz to simulate a continuous wave excitation source. Detection limits were found to vary with pulse rate, as expected, in proportion to average excitation power. The following detection limits (3sigma) were determined in free solution CE: tryptophan, 4 nM; conalbumin, 10 nM; alpha-lactalbumin, 30 nM. Detection limits for indole-based compounds and catecholamine urinary metabolites under MEKC separation conditions were in the range 7-170 nM.
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Affiliation(s)
- D M Paquette
- Department of Chemistry and Biochemistry, Concordia University, Montréal, Québec, Canada
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38
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Lindberg P, Hanning A, Lindberg T, Roeraade J. Fiber-optic-based UV–visible absorbance detector for capillary electrophoresis, utilizing focusing optical elements. J Chromatogr A 1998. [DOI: 10.1016/s0021-9673(98)00145-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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39
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Abstract
During the past decade, capillary electrophoresis (CE) emerged as a promising, effective and economic approach for separation of a large variety of substances, including those encountered in clinical toxicology. Reliable and automated CE instruments became commercially available and promoted the exploration of an increasing number of CE methods for illicit and licit drugs in body fluids. The widespread applicability of CE, its enormous separation power and high-sensitivity detection schemes make this technology an attractive and promising tool. This review provides an overview of the key achievements encountered with CE in clinical toxicology, including (i) the rapid assessment of drug intoxications via direct sample injection, (ii) the screening for and determination of illicit and licit drugs in body fluids with drug extraction, drug concentration (stacking) and chiral discrimination, (iii) the application of immunological single and multianalyte assays in the capillary format to the screening for drugs in body fluids, and (iv) drug confirmation by on-column multiwavelength absorbance and fluorescence detection and/or CE coupled to mass spectrometry. With its distinct features (automation, small sample size, minimal sample preparation, requirement of almost no organic solvents, ease of buffer change and method development, speed of analysis, low cost of capillaries and chemicals) CE has a bright future and the twenty-first century will witness the widespread use of a large number of simple and reliable CE based assays for drugs, methods that will be employed in clinical toxicology, therapeutic drug monitoring and forensic science.
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Affiliation(s)
- W Thormann
- Department of Clinical Pharmacology, University of Bern, Switzerland.
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40
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Abstract
During the past decade, capillary electrophoresis (CE) emerged as a promising, effective and economic approach for separation of a large variety of substances, including those encountered in clinical and forensic analysis. Reliable and automated CE instruments became commercially available and promoted the exploration of an increasing number of CE methods and fields of application. The widespread applicability of CE, its enormous separation power and high-sensitivity detection schemes make this technology an attractive and promising tool. This review discusses the principles and important aspects of CE-based assays and provides an overview of the key achievements encountered with CE in clinical and forensic analysis, including those associated with the analysis of serum proteins, hemoglobin variants, drugs and nucleic acids. Validated assays, interesting applications and future trends in clinical and forensic analysis are also discussed.
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Affiliation(s)
- F von Heeren
- Department of Clinical Pharmacology, University of Bern, Switzerland
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41
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Albrecht C, Reichen J, Visser J, Meijer DKF, Thormann W. Differentiation between naproxen, naproxen–protein conjugates, and naproxen–lysine in plasma via micellar electrokinetic capillary chromatography—a new approach in the bioanalysis of drug targeting preparations. Clin Chem 1997. [DOI: 10.1093/clinchem/43.11.2083] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
Pharmacotherapy through the targeting of drugs is a promising new approach that requires adequate analytical methods capable of differentiating between the free drug, the drug carrier, and metabolites. Using micellar electrokinetic capillary chromatography (MECC), we report the separation of naproxen (NAP) from NAP covalently coupled to human serum albumin or to mannosylated serum albumin and the metabolite naproxen–lysine. An assay for selective analysis of the different forms of NAP by direct plasma injection was developed with salicylate as internal standard and solute detection by laser-induced fluorescence. Compared with previously applied techniques, including HPLC and total plasma fluorescence, MECC offers the advantage that free and covalently bound NAP can be differentiated in one run and can be accurately monitored in microliter quantities of plasma. Summation of all NAP equivalents determined by MECC revealed data that compare well with those produced by total plasma fluorescence and HPLC.
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Affiliation(s)
- Christiane Albrecht
- Department of Clinical Pharmacology, University of Bern, Murtenstr. 35, 3010 Bern, Switzerland
| | - Jürg Reichen
- Department of Clinical Pharmacology, University of Bern, Murtenstr. 35, 3010 Bern, Switzerland
| | - Jan Visser
- Department of Pharmacokinetics and Drug Delivery, University of Groningen, Antonius Deusinglaan 2, 9713 AV Groningen, The Netherlands
| | - Dirk K F Meijer
- Department of Pharmacokinetics and Drug Delivery, University of Groningen, Antonius Deusinglaan 2, 9713 AV Groningen, The Netherlands
| | - Wolfgang Thormann
- Department of Clinical Pharmacology, University of Bern, Murtenstr. 35, 3010 Bern, Switzerland
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42
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Lehmann R, Voelter W, Liebich HM. Capillary electrophoresis in clinical chemistry. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1997; 697:3-35. [PMID: 9342655 DOI: 10.1016/s0378-4347(97)00183-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Since its introduction, capillary electrophoresis has diversified, spreading out into different specialized fields covering solutions for almost any analytical questions arising in research laboratories. In the context of clinical chemistry, results must be provided at low costs and in a clinically relevant time frame; however, the attributes which have made capillary electrophoresis such a successful tool in basic research are identical to those attracting clinical laboratories: speed (more efficient, less labor-intensive), low costs (minimal buffer consumption), small sample volume (reduced blood collection volume from patient), increased selectivity (determination of multiple solutes in one run), and versatility (detection of analytes over the wide range of molecular masses and chemical composition). Nevertheless, it should be mentioned that there are still some drawbacks at this stage to be solved in the near future, such as lack of sensitivity for many clinical applications or the constraint to measure in a sequential mode. The aim of this survey is to familiarize clinical chemists, as well as chemists, with a short introduction to capillary electrophoresis, followed by chapters reviewing prominent fields of applications and the latest developments in clinical chemistry.
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Affiliation(s)
- R Lehmann
- Abteilung Innere Medizin IV, Stoffwechselkrankheiten und Klinische Chemie, Medizinische Klinik und Poliklinik der Universität, Tübingen, Germany
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Guzman NA, Park SS, Schaufelberger D, Hernandez L, Paez X, Rada P, Tomlinson AJ, Naylor S. New approaches in clinical chemistry: on-line analyte concentration and microreaction capillary electrophoresis for the determination of drugs, metabolic intermediates, and biopolymers in biological fluids. JOURNAL OF CHROMATOGRAPHY. B, BIOMEDICAL SCIENCES AND APPLICATIONS 1997; 697:37-66. [PMID: 9342656 DOI: 10.1016/s0378-4347(97)00275-2] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The use of capillary electrophoresis (CE) for clinically relevant assays is attractive since it often presents many advantages over contemporary methods. The small-diameter tubing that holds the separation medium has led to the development of multicapillary instruments, and simultaneous sample analysis. Furthermore, CE is compatible with a wide range of detectors, including UV-Vis, fluorescence, laser-induced fluorescence, electrochemistry, mass spectrometry, radiometric, and more recently nuclear magnetic resonance, and laser-induced circular dichroism systems. Selection of an appropriate detector can yield highly specific analyte detection with good mass sensitivity. Another attractive feature of CE is the low consumption of sample and reagents. However, it is paradoxical that this advantage also leads to severe limitation, namely poor concentration sensitivity. Often high analyte concentrations are required in order to have injection of sufficient material for detection. In this regard, a series of devices that are broadly termed 'analyte concentrators' have been developed for analyte preconcentration on-line with the CE capillary. These devices have been used primarily for non-specific analyte preconcentration using packing material of the C18 type. Alternatively, the use of very specific antibody-containing cartridges and enzyme-immobilized microreactors have been demonstrated. In the current report, we review the likely impact of the technology of capillary electrophoresis and the role of the CE analyte concentrator-microreactor on the analysis of biomolecules, present on complex matrices, in a clinical laboratory. Specific examples of the direct analysis of physiologically-derived fluids and microdialysates are presented, and a personal view of the future of CE in the clinical environment is given.
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Affiliation(s)
- N A Guzman
- R. W. Johnson Pharmaceutical Research Institute, Raritan, NJ 08869, USA
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Kunkel A, Günter S, Wätzig H. Determination of pharmaceuticals in plasma by capillary electrophoresis without sample pretreatment reproducibility, limit of quantitation and limit of detection. Electrophoresis 1997; 18:1882-9. [PMID: 9372284 DOI: 10.1002/elps.1150181026] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Pharmaceuticals in human plasma are determined on underivatized fused-silica capillaries by micellar electrokinetic capillary chromatography (MEKC) without sample pretreatment. Our best method to date uses as running buffer a sodium dodecyl sulfate (SDS) containing borate buffer (60 mM with 200 mM SDS) at pH 10. Between runs, proteins adsorbed to the capillary wall are removed by an acetonitrile and SDS-buffer rinsing regimen (50% v/v each). A day-to-day precision for relative peak areas of about 2% relative standard deviation (RSD; n > 40) has been reached. Different rinsing approaches are discussed (salts, enzyme-containing solutions, organic solvents, hydrofluoric acid). The separation system is tested in a concentration range between approximately 100 mg/L-10 mg/L. Correlations between the limit of quantitation, the limit of detection and the signal/noise are discussed. The applicability of the system is demonstrated for the pharmaceuticals acetaminophen, salicylic acid, sulfamethoxazole, tolbutamide, and trimethoprim.
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Affiliation(s)
- A Kunkel
- Institute of Pharmacy and Food Chemistry, University of Würzburg, Germany
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45
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Alfazema LN, Hows ME, Howells S, Perrett D. Micellar electrokinetic capillary chromatography (MECC) of UV-absorbing constituents in normal urine: a chemometric optimisation of the separation. Electrophoresis 1997; 18:1847-56. [PMID: 9372279 DOI: 10.1002/elps.1150181021] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A micellar electrokinetic capillary chromatography (MECC) method when compared to free solution capillary electrophoresis (CZE) was shown to offer improved selectivity and resolution for the separation of UV-absorbing components of human urine. Some of the factors affecting MECC separation e.g. methanol concentration, sodium dodecyl sulphate (SDS) concentration, beta-cyclodextrin (beta-CD) concentration, voltage, pH, temperature and electrolyte additives (urea, beta-CD and Brij 35) were optimised using chemometric techniques. Three-level three-factor (3(3)) factorial designs and simplex optimisation were used to achieve optimised conditions with the goal of obtaining the maximum number of peaks in the shortest possible analysis time. Using a TSP CE2000 instrument with detection from 195-300 nm and fitted with a 75 microns x 44 cm (37 cm effective length) fused silica capillary the final optimum conditions were found to be, an electrolyte consisting of 30 mM sodium tetraborate, pH 10, containing 75 mM SDS and 10 mM beta-CD, 15 degrees C, 20 kV, 4 s hydrodynamic injection of filtered urine. These conditions were capable of separating 70 peaks from a normal human urine pool in less than 12 min. The separation of components in urine using the optimised MECC was simpler, more reproducible, faster and gave better resolution than gradient reversed-phase high performance liquid chromatography.
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Affiliation(s)
- L N Alfazema
- Department of Chemistry, University of Greenwich, London, UK
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46
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Shihabi ZK, Friedberg MA. Analysis of small molecules for clinical diagnosis by capillary electrophoresis. Electrophoresis 1997; 18:1724-32. [PMID: 9372263 DOI: 10.1002/elps.1150181005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The application of capillary electrophoresis (CE) for the analysis of small molecules in clinical research is growing steadily. Initial studies have dealt with separations of standards or compounds in clean matrices. However, later studies dealt with analysis of those compounds in serum, urine or tissues. Great progress has been accomplished in three areas of clinical interest: organic acids, amino acids and drug analysis. The analysis of these compounds by capillary electrophoresis has several distinct advantages: high resolution, simplicity, versatility and especially low operating costs. In many cases, the sample can be injected directly without complex pretreatment. Most of the described methods have been validated for their precision, linearity and accuracy. In forensic toxicology, the CE has been used for drug identification and as a complementary analytical method.
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Affiliation(s)
- Z K Shihabi
- Department of Pathology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, NC 27157, USA.
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Anderson DJ, Guo B, Xu Y, Ng LM, Kricka LJ, Skogerboe KJ, Hage DS, Schoeff L, Wang J, Sokoll LJ, Chan DW, Ward KM, Davis KA. Clinical chemistry. Anal Chem 1997; 69:165R-229R. [PMID: 9195857 DOI: 10.1021/a1970008p] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- D J Anderson
- Department of Chemistry, Cleveland State University, Ohio 44115, USA
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49
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Abstract
Capillary electrophoresis (CE) is a separation technique particularly suited to the analysis of pharmaceutical compounds. This review offers a detailed discussion of the four common modes of detection coupled to CE-UV absorption, fluorescence, electrochemical, and mass spectrometry-and gives examples of the use of these methods in pharmaceutical analyses. Sample preparation and pretreatment techniques used for CE separations are described, as well as methods of preconcentration including hydrophobic retention, affinity concentration, sample stacking, and isotachophoresis. The use of affinity CE, chiral CE, and capillary gel electrophoresis for analysis of pharmaceuticals is covered in detail, and recent advances in capillary electrochromatography and CE on a chip are also discussed.
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Affiliation(s)
- L A Holland
- Department of Pharmaceutical Chemistry, University of Kansas, Lawrence 66047, USA
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50
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Herderich M, Gutsche B. Tryptophan‐derived bioactive compounds in food. FOOD REVIEWS INTERNATIONAL 1997. [DOI: 10.1080/87559129709541100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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