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Clozapine and norclozapine monitoring in plasma following surfactant assisted dispersive liquid–liquid microextraction. SEPARATION SCIENCE PLUS 2022. [DOI: 10.1002/sscp.202100068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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2
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Senel M, Alachkar A. Lab-in-a-pencil graphite: A 3D-printed microfluidic sensing platform for real-time measurement of antipsychotic clozapine level. LAB ON A CHIP 2021; 21:405-411. [PMID: 33331378 DOI: 10.1039/d0lc00970a] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A novel lab-in-a-pencil graphite microfluidic sensing electrode (μFSE) was fabricated for real-time flow injection measurement of the antipsychotic drug clozapine (Clz). A simple, low-cost, and reusable μFSE was obtained by using 3D printing of a microfluidic chamber integrated with a flat pencil graphite without the need to utilize complex technologies. The μFSE has tubular geometry with 800 μm diameter, where the solution continuously flows in the holes of flat pencil graphite electrodes. Under optimized conditions, this device offers fast and effective Clz detection with good analytical features. A linear calibration curve in the range of 0.5 to 10 μM Clz was obtained with good sensitivity (0.01275 μA μM-1) and detection limit (24 nM). Finally, we demonstrate the applicability of our lab-fabricated microfluidic electrochemical device by monitoring Clz in serum samples at low concentrations.
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Affiliation(s)
- Mehmet Senel
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, University of California, Irvine, CA 92697-4625, USA.
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3
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Li X, Yang Y, Miao J, Yin Z, Zhai Y, Shi H, Li Z. Determination of sulfa antibiotic residues in river and particulate matter by field-amplified sample injection-capillary zone electrophoresis. Electrophoresis 2020; 41:1584-1591. [PMID: 32683752 DOI: 10.1002/elps.202000122] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 07/14/2020] [Accepted: 07/15/2020] [Indexed: 12/18/2022]
Abstract
In the present research, field-amplified sample injection-CZE (FASI-CZE) coupled with a diode array detector was established to determine trace level sulfa antibiotic. Sulfathiazole, sulfadiazine, sulfamethazine, sulfadimethoxine, sulfamethoxazole, and sulfisoxazole were selected as analytes for the experiments. The background electrolyte solution consisted of 70.0 mmol/L borax and 60.0 mmol/L boric acid (including 10% methanol, pH 9.1). The plug was 2.5 mmol/L borax, which was injected into the capillary at a pressure of 0.5 psi for 5 s. Then the sample was injected into the capillary at an injection voltage of -10 kV for 20 s. The electrophoretic separation was carried out under a voltage of +19 kV. The capillary temperature was maintained at 20˚C throughout the analysis, and six sulfonamides were completely separated within 35 min. Compared with pressure injection-CZE, the sensitivity of FASI-CZE was increased by 6.25-10.0 times, and the LODs were reduced from 0.2-0.5 to 0.02-0.05 μg/mL. The method was applied to the determination of sulfonamides in river water and particulate matter samples. The recoveries were 78.59-106.59%. The intraday and interday precisions were 2.89-7.35% and 2.77-7.09%, respectively. This provides a simpler and faster method for the analysis of sulfa antibiotic residues in environmental samples.
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Affiliation(s)
- Xinghua Li
- School of Public Health, and Key Laboratory of Environment and Human Health of Hebei Province, Hebei Medical University, Shijiazhuang, P. R. China
| | - Yuqin Yang
- School of Public Health, and Key Laboratory of Environment and Human Health of Hebei Province, Hebei Medical University, Shijiazhuang, P. R. China
| | - Junjie Miao
- School of Public Health, and Key Laboratory of Environment and Human Health of Hebei Province, Hebei Medical University, Shijiazhuang, P. R. China
| | - Zhendong Yin
- School of Public Health, and Key Laboratory of Environment and Human Health of Hebei Province, Hebei Medical University, Shijiazhuang, P. R. China
| | - Yijing Zhai
- Department of Nutrition, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China
| | - Hongmei Shi
- School of Public Health, and Key Laboratory of Environment and Human Health of Hebei Province, Hebei Medical University, Shijiazhuang, P. R. China
| | - Zengning Li
- Department of Nutrition, The First Hospital of Hebei Medical University, Shijiazhuang, P. R. China
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Rouhollahi A, Kouchaki M, Seidi S. Electrically stimulated liquid phase microextraction combined with differential pulse voltammetry: a new and efficient design for in situ determination of clozapine from complicated matrices. RSC Adv 2016. [DOI: 10.1039/c5ra25157e] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Electromembrane extraction combined with differential pulse voltammetry for in situ determination of clozapine from complicated matrices.
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Affiliation(s)
- Ahmad Rouhollahi
- Department of Analytical Chemistry
- Faculty of Chemistry
- K. N. Toosi University of Technology
- Tehran
- Iran
| | - Masoomeh Kouchaki
- Department of Analytical Chemistry
- Faculty of Chemistry
- K. N. Toosi University of Technology
- Tehran
- Iran
| | - Shahram Seidi
- Department of Analytical Chemistry
- Faculty of Chemistry
- K. N. Toosi University of Technology
- Tehran
- Iran
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Lian DS, Zhao SJ. Highly sensitive analysis of nucleic acids using capillary gel electrophoresis with ultraviolet detection based on the combination of matrix field-amplified and head-column field-amplified stacking injection. J Chromatogr B Analyt Technol Biomed Life Sci 2015; 978-979:29-42. [DOI: 10.1016/j.jchromb.2014.11.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/16/2014] [Accepted: 11/20/2014] [Indexed: 12/17/2022]
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Rossetti DV, Martelli C, Longhi R, Iavarone F, Castagnola M, Desiderio C. Quantitative analysis of thymosin β4 in whole saliva by capillary electrophoresis–mass spectrometry using multiple ions monitoring (CE-MIM-MS.). Electrophoresis 2014; 34:2674-82. [PMID: 23857244 DOI: 10.1002/elps.201300165] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Revised: 06/25/2013] [Accepted: 07/02/2013] [Indexed: 12/18/2022]
Abstract
Thymosin β4 (Tβ4) is a peptide present in almost any tissue and in extracellular media in mammals, having multiple amazing functions as wound healing, stimulation of angiogenesis, and suppression of inflammation. This study describes its determination in saliva through CE-MS using multiple ions monitoring scan mode by isolating the four most intense multicharged ions present in the MS spectra of the peptide. This scan modality, by reducing the baseline noise and interferences, increases the sensitivity and specificity in biological matrices. The CE-MS separation was optimized by studying different parameters influencing CE analysis, sample injection, and MS ionization, that is, the nebulizer gas flow, the sheath liquid, and BGE composition. The proposed technique can unambiguously identify in short time Tβ4 in saliva after a very fast and reduced sample pretreatment procedure. The method was validated for quantitation showing linearity of the response in the range 0.25 (lower limit of quantification) to 4 μM (average R2 0.996 ± 0.005) and intra- and interassay precision and accuracy at three different concentrations with RSD values in the range of 7–16%. It was successfully applied to the analysis of Tβ4 in whole saliva showing a variable peptide content from individual to individual (in the range of 0.3–1.4 μM) and in different days from the same individual. CE-MS in multiple ions monitoring scan mode provides a fast, selective, and economic method requiring only very few microliters of sample.
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Haas SE, Brum L, de Andrade C, Azeredo FJ, Pigatto M, Silva Torres BG, Guterres SS, Costa TD. HIGHLY SENSITIVE LC-MS/MS METHOD FOR THE DETERMINATION OF CLOZAPINE IN RAT PLASMA: APPLICATION TO A PRECLINICAL PHARMACOKINETIC STUDY. J LIQ CHROMATOGR R T 2012. [DOI: 10.1080/10826076.2011.639118] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- Sandra Elisa Haas
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
| | - Liberato Brum
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
| | - Cristiane de Andrade
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
| | - Francine Johansson Azeredo
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
| | - Maiara Pigatto
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
| | - Bruna Gaelzer Silva Torres
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
| | - Silvia Staniçuaski Guterres
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
| | - Teresa Dalla Costa
- a Programa de Pós-Graduação em Ciências Farmacêuticas, Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul , Porto Alegre , Rio Grande do Sul , Brazil
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Wohlfarth A, Toepfner N, Hermanns-Clausen M, Auwärter V. Sensitive quantification of clozapine and its main metabolites norclozapine and clozapine-N-oxide in serum and urine using LC-MS/MS after simple liquid–liquid extraction work-up. Anal Bioanal Chem 2011; 400:737-46. [DOI: 10.1007/s00216-011-4831-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2010] [Revised: 02/19/2011] [Accepted: 02/21/2011] [Indexed: 10/18/2022]
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9
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Breadmore MC. Ionic liquid-based liquid phase microextraction with direct injection for capillary electrophoresis. J Chromatogr A 2011; 1218:1347-52. [DOI: 10.1016/j.chroma.2011.01.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2010] [Revised: 12/21/2010] [Accepted: 01/07/2011] [Indexed: 10/18/2022]
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Li J, Jiang Y. Rapid and sensitive determination of strychnine and brucine in human urine by capillary electrophoresis with field-amplified sample stacking. Biomed Chromatogr 2009; 24:186-94. [PMID: 19609870 DOI: 10.1002/bmc.1270] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A simple, rapid, sensitive and low-cost method using capillary electrophoresis (CE) coupled with field-amplified sample stacking (FASS) has been developed and validated for the simultaneous determination of strychnine and brucine residues in human urine. Before sample loading, a water plug (3.5 kPa, 3 s) was injected to contain sample cations and to permit FASS. Electrokinetic injection at a voltage (20 kV, 25 s) was then used to introduce cations. Separation was performed using 20 mM acetate buffer (pH 3.8) with an applied voltage of 20 kV. The calibration curves were linear over a range of 8.00-2.56 infinity 10(2) ng/mL (r = 0.9995) for strychnine and 10.0-3.20 x 10(2) ng/mL (r = 0.9999) for brucine. Extraction recoveries in urine were greater than 79.6 and 82.8% for strychnine and brucine, respectively, with an RSD of less than 4.9%. The detection limits (signal-to-noise ratio 3) for strychnine and brucine were 2.00 and 2.50 ng/mL, respectively. A urine sample from one healthy female volunteer (26 years old, 50 kg) was pretreated and analyzed. Strychnine and brucine levels in urine could be detected 24 h after administration. On these grounds, this method was feasible for application to preliminary screening of trace levels of abused drugs for both doping control and forensic analysis.
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Affiliation(s)
- Junmei Li
- Department of Pharmaceutical Analysis, School of Pharmacy, Hebei Medical University, 361 East Zhongshan Road, Shijiazhuang City, People's Republic of China
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Song M, Yu X, Zhao H, Hang T, Yang L, Xu W. LC-MS-MS Determination and Pharmacokinetic Study of Clozapine in Human Plasma. Chromatographia 2009. [DOI: 10.1365/s10337-009-0975-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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12
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Hai X, Konečnỳ J, Zeisbergerová M, Adams E, Hoogmartens J, Schepdael AV. Development of electrophoretically mediated microanalysis method for the kinetics study of flavin‐containing monooxygenase in a partially filled capillary. Electrophoresis 2008; 29:3817-24. [DOI: 10.1002/elps.200800138] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Xin Hai
- Laboratory for Pharmaceutical Analysis, K.U. Leuven, Leuven, Belgium
| | - Jiří Konečnỳ
- Department of Biochemistry, Masaryk University, Brno, Czech Republic
| | - Marta Zeisbergerová
- Laboratory for Pharmaceutical Analysis, K.U. Leuven, Leuven, Belgium
- Department of Biochemistry, Masaryk University, Brno, Czech Republic
| | - Erwin Adams
- Laboratory for Pharmaceutical Analysis, K.U. Leuven, Leuven, Belgium
| | - Jos Hoogmartens
- Laboratory for Pharmaceutical Analysis, K.U. Leuven, Leuven, Belgium
| | - Ann Van Schepdael
- Laboratory for Pharmaceutical Analysis, K.U. Leuven, Leuven, Belgium
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13
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Zhang G, Jr AVT, Bartlett MG. Bioanalytical methods for the determination of antipsychotic drugs. Biomed Chromatogr 2008; 22:671-87. [DOI: 10.1002/bmc.997] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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14
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Simpson SL, Quirino JP, Terabe S. On-line sample preconcentration in capillary electrophoresis. J Chromatogr A 2008; 1184:504-41. [DOI: 10.1016/j.chroma.2007.11.001] [Citation(s) in RCA: 269] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Revised: 10/30/2007] [Accepted: 11/01/2007] [Indexed: 02/06/2023]
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15
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Natishan TK. Recent Progress in the Analysis of Pharmaceuticals by Capillary Electrophoresis. J LIQ CHROMATOGR R T 2007. [DOI: 10.1081/jlc-200053014] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Theresa K. Natishan
- a Merck & Co., Inc. , Merck Research Laboratories, Analytical Research , Rahway, New Jersey, USA
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Malá Z, Krivánková L, Gebauer P, Bocek P. Contemporary sample stacking in CE: A sophisticated tool based on simple principles. Electrophoresis 2007; 28:243-53. [PMID: 17136738 DOI: 10.1002/elps.200600397] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Sample stacking is a general term for methods in CE which are used for on-line concentration of diluted analytes. During the stacking process, analytes present at low concentrations in a long injected sample zone are concentrated into a short zone (stack). The stacked analytes are then separated and individual zones are detected. Thus stacking provides better separation efficiency and detection sensitivity. Many papers have been published on stacking till now, various procedures have been described, and, many names have been proposed for stacking procedures utilizing the same principles. This contribution brings an easy and unified view on stacking, describes the basic principles utilized, makes a list of recognized operational principles and brings an overview of principal current procedures. Further, it surveys selected recent practical applications ordered according to their operational principles and includes the terms, nicknames, and acronyms used for these actual stacking procedures. This contribution may help both newcomers and experts in the field of CE to orient themselves in the already quite complex topic of sample stacking.
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Affiliation(s)
- Zdena Malá
- Institute of Analytical Chemistry, Academy of Sciences of the Czech Republic, Brno, Czech Republic
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Hoque ME, Arnett SD, Lunte CE. On-column preconcentration of glutathione and glutathione disulfide using pH-mediated base stacking for the analysis of microdialysis samples by capillary electrophoresis. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 827:51-7. [PMID: 15996908 PMCID: PMC2440695 DOI: 10.1016/j.jchromb.2005.05.038] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2005] [Revised: 05/09/2005] [Accepted: 05/13/2005] [Indexed: 11/18/2022]
Abstract
Capillary electrophoresis (CE) has become a useful analytical tool for the analysis of microdialysis samples. However, CE with UV detection (CE-UV) does not provide detection limits sufficient to quantify glutathione (GSH) and glutathione disulfide (GSSG) in biological samples such as liver microdialysates, because of the small optical path length in the capillary. To overcome this limitation, an on-column preconcentration technique, pH-mediated base stacking, was used in this study to improve the sensitivity of CE-UV. This stacking technique allowed large volumes of high ionic strength sample injection without deterioration of the separation efficiency and resolution. A 26-fold increase in sensitivity was achieved for both GSH and GSSG using the pH-mediated base stacking, relative to normal injection without stacking. The limit of detection for GSH and GSSG was found to be 0.75 microM (S/N=6) and 0.25 microM (S/N=6), respectively. The developed method was used to analyze GSH and GSSG in liver microdialysates of anesthetized Sprague Dawley male rats. The basal concentrations of GSH and GSSG in the liver microdialysates of male rats were found to be 4.73+/-2.08 microM (n=7) and 5.52+/-3.66 microM (n=7), respectively.
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Affiliation(s)
| | - Stacy D. Arnett
- Department of Chemistry, University of Kansas, Lawrence, KS 66045
| | - Craig E. Lunte
- Department of Chemistry, University of Kansas, Lawrence, KS 66045
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Yu L, Li SFY. Dynamic pH junction-sweeping capillary electrophoresis for online preconcentration of toxic pyrrolizidine alkaloids in Chinese herbal medicine. Electrophoresis 2005; 26:4360-7. [PMID: 16240296 DOI: 10.1002/elps.200500267] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
There is a need to develop simple yet effective preconcentration methods to enhance concentration sensitivity for CE analysis of trace level analytes in real samples, particularly when commonly available but less sensitive detection methods, e.g., UV detection, are used. In this report, a hyphenated online preconcentration strategy combining dynamic pH junction with sweeping (i.e., dynamic pH junction-sweeping) was employed for the analysis of four toxic pyrrolizidine alkaloids (PAs) of senkirkine, senecionine, retrorsine, and seneciphylline in Chinese herbal medicine (Kuan donghua). Direct electrokinetically focusing of a large sample volume injection (up to 20% of capillary length) on the capillary was performed using the dynamic pH junction-sweeping method. A sample matrix consisting of 10 mM phosphate with 20% methanol at pH 4.0 and a BGE containing 20 mM borate, 30 mM SDS, and 20% methanol at pH 9.1 were utilized to realize dynamic pH junction-sweeping for PAs. This online preconcentration strategy resulted in sensitivity enhancement factors ranging from 23.8- to 90.0-fold for the four toxic PAs, giving an LOD as low as 30 ppb for the PAs. Critical factors such as sample matrix type, pH, and salt concentration were also examined to achieve higher sensitivity enhancement, shorter analysis time, and better resolution. The results indicate that the proposed dynamic pH junction-sweeping technique is a powerful alternative approach for identification and determination of trace levels of these toxic PAs and other hydrophobic, protonatable compounds in real samples.
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Affiliation(s)
- Lijun Yu
- Department of Chemistry, National University of Singapore
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Lara FJ, García-Campaña AM, Alés-Barrero F, Bosque-Sendra JM. Development and validation of a capillary electrophoresis method for the determination of phenothiazines in human urine in the low nanogramper milliliter concentration range using field-amplified sample injection. Electrophoresis 2005; 26:2418-29. [PMID: 15924366 DOI: 10.1002/elps.200500098] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A capillary zone electrophoresis (CZE) method with ultraviolet-visible detection has been established and validated for the determination of five phenothiazines: thiazinamium methylsulfate, promazine hydrochloride, chlorpromazine hydrochloride, thioridazine hydrochloride, and promethazine hydrochloride in human urine. Optimum separation was obtained on a 64.5 cm x 75 microm bubble cell capillary using a buffer containing 150 mM tris(hydroxymethyl)aminomethane and 25% acetonitrile at pH 8.2, with temperature and voltage of 25 degrees C and 20 kV, respectively. Naphazoline hydrochloride was used as an internal standard. Field-amplified sample injection (FASI) has been applied to improve the sensitivity of the detection. Considering the influence of parameters affecting the on-line preconcentration (nature of preinjection plug, sample solvent composition, injection times, and injection voltage) and due to the significant interactions among them, in this paper we propose for the first time the application of a multivariate approach to carry out the study. The optimized conditions were as follows: preinjection plug of water for 7 s at 50 mbar, electrokinetic injection for 40 s at 6.2 kV, and 32 microm of H3PO4 in the sample solvent. Also, a solid-phase extraction (SPE) procedure is developed to obtain low detection limits and an adequate selectivity for urine samples. The combination of SPE and FASI-CZE-UV allows adequate linearities and recoveries, low detection limits (from 2 to 5 ng/mL), and satisfactory precisions (3.0-7.2% for an intermediate RSD %).
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Affiliation(s)
- Francisco J Lara
- Department of Analytical Chemistry, Faculty of Sciences, University of Granada, Granada, Spain
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