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Celá A, Glatz Z. Homocyclic
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‐dicarboxaldehydes: Derivatization reagents for sensitive analysis of amino acids and related compounds by capillary and microchip electrophoresis. Electrophoresis 2020; 41:1851-1869. [DOI: 10.1002/elps.202000041] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2020] [Revised: 05/27/2020] [Accepted: 06/07/2020] [Indexed: 01/01/2023]
Affiliation(s)
- Andrea Celá
- Department of Biochemistry, Faculty of Science Masaryk University Brno Czech Republic
| | - Zdeněk Glatz
- Department of Biochemistry, Faculty of Science Masaryk University Brno Czech Republic
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2
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Sensitive amperometric detection for capillary electrophoresis of phenol carbamates with in‐line thermal hydrolysis strategy. Electrophoresis 2019; 40:1648-1655. [DOI: 10.1002/elps.201800484] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 03/24/2019] [Accepted: 03/26/2019] [Indexed: 12/17/2022]
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3
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A new cyano-substituted fluorescamine superior to its original form as a fluorescent probe for amino acid detection. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.02.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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4
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Abstract
Capillary electrophoresis is a well-established separation technique in analytical research laboratories worldwide. Its interesting advantages make CE an efficient and potent alternative to other chromatographic techniques. However, it is also recognized that its main drawback is the relatively poor sensitivity when using optical detection. One way to overcome this limitation is to perform a derivatization reaction which is intended to provide the analyte more suitable analytical characteristics enabling a high sensitive detection. Based on the analytical step where the CE derivatization takes place, it can be classified as precapillary (before separation), in-capillary (during separation), or postcapillary (after separation). This chapter describes the application of four different derivatization protocols (in-capillary and precapillary modes) to carry out the achiral and chiral analysis of different compounds in food and biological samples with three different detection modes (UV, LIF, and MS).
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Affiliation(s)
- M Luisa Marina
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology, Environmental Sciences and Chemistry, University of Alcalá, Ctra. Madrid-Barcelona Km. 33.600, Alcalá de Henares, Madrid, 28871, Spain
| | - María Castro-Puyana
- Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Biology, Environmental Sciences and Chemistry, University of Alcalá, Ctra. Madrid-Barcelona Km. 33.600, Alcalá de Henares, Madrid, 28871, Spain.
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5
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Khan P, Idrees D, Moxley MA, Corbett JA, Ahmad F, von Figura G, Sly WS, Waheed A, Hassan MI. Luminol-based chemiluminescent signals: clinical and non-clinical application and future uses. Appl Biochem Biotechnol 2014; 173:333-55. [PMID: 24752935 PMCID: PMC4426882 DOI: 10.1007/s12010-014-0850-1] [Citation(s) in RCA: 185] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2013] [Accepted: 03/06/2014] [Indexed: 12/28/2022]
Abstract
Chemiluminescence (CL) is an important method for quantification and analysis of various macromolecules. A wide range of CL agents such as luminol, hydrogen peroxide, fluorescein, dioxetanes and derivatives of oxalate, and acridinium dyes are used according to their biological specificity and utility. This review describes the application of luminol chemiluminescence (LCL) in forensic, biomedical, and clinical sciences. LCL is a very useful detection method due to its selectivity, simplicity, low cost, and high sensitivity. LCL has a dynamic range of applications, including quantification and detection of macro and micromolecules such as proteins, carbohydrates, DNA, and RNA. Luminol-based methods are used in environmental monitoring as biosensors, in the pharmaceutical industry for cellular localization and as biological tracers, and in reporter gene-based assays and several other immunoassays. Here, we also provide information about different compounds that may enhance or inhibit the LCL along with the effect of pH and concentration on LCL. This review covers most of the significant information related to the applications of luminol in different fields.
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Affiliation(s)
- Parvez Khan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Danish Idrees
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Michael A. Moxley
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., DRC Room 615, St. Louis, MO, USA
| | - John A. Corbett
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Faizan Ahmad
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
| | - Guido von Figura
- Department of Internal Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - William S. Sly
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., DRC Room 615, St. Louis, MO, USA
| | - Abdul Waheed
- Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, 1100 S. Grand Blvd., DRC Room 615, St. Louis, MO, USA
| | - Md. Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110025, India
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6
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Liquid chromatography coupled to on-line post column derivatization for the determination of organic compounds: A review on instrumentation and chemistries. Anal Chim Acta 2013; 798:1-24. [DOI: 10.1016/j.aca.2013.07.032] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Revised: 07/07/2013] [Accepted: 07/11/2013] [Indexed: 11/23/2022]
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7
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Construction of post-column micro-membrane reactor for protein analysis in capillary electrophoresis with laser induced fluorescence detection. Chem Res Chin Univ 2013. [DOI: 10.1007/s40242-013-3201-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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8
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Liu F, Zhang L, Qian J, Ren J, Gao F, Zhang W. A novel, post-column micro-membrane reactor for fluorescent analysis of protein in capillary electrophoresis. Analyst 2013; 138:6429-36. [DOI: 10.1039/c3an00953j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Yu CZ, He YZ, Han F, Fu GN. Post-column reactor of coaxial-gap mode for laser-induced fluorescence detection in capillary electrophoresis. J Chromatogr A 2007; 1171:133-9. [DOI: 10.1016/j.chroma.2007.09.046] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2007] [Revised: 09/14/2007] [Accepted: 09/17/2007] [Indexed: 10/22/2022]
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10
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Yamamoto D, Kaneta T, Imasaka T. Postcolumn reactor using a laser-drilled capillary for light-emitting diode-induced fluorescence detection in CE. Electrophoresis 2007; 28:4143-9. [DOI: 10.1002/elps.200700274] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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11
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Field-amplified sample injection and in-capillary derivatization for capillary electrophoretic analysis of metal ions in local wines. Microchem J 2007. [DOI: 10.1016/j.microc.2007.03.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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12
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Boudko DY. Bioanalytical profile of the L-arginine/nitric oxide pathway and its evaluation by capillary electrophoresis. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 851:186-210. [PMID: 17329176 PMCID: PMC2040328 DOI: 10.1016/j.jchromb.2007.02.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2006] [Revised: 01/30/2007] [Accepted: 02/06/2007] [Indexed: 02/07/2023]
Abstract
This review briefly summarizes recent progress in fundamental understanding and analytical profiling of the L-arginine/nitric oxide (NO) pathway. It focuses on key analytical references of NO actions and the experimental acquisition of these references in vivo, with capillary electrophoresis (CE) and high-performance capillary electrophoresis (HPCE) comprising one of the most flexible and technologically promising analytical platform for comprehensive high-resolution profiling of NO-related metabolites. Another aim of this review is to express demands and bridge efforts of experimental biologists, medical professionals and chemical analysis-oriented scientists who strive to understand evolution and physiological roles of NO and to develop analytical methods for use in biology and medicine.
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Affiliation(s)
- Dmitri Y Boudko
- The Whitney Laboratory for Marine Bioscience, 9505 Ocean Shore Blvd., St. Augustine, FL 32080, USA.
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Abstract
CE- and microchip-based separations coupled with LIF are powerful tools for the separation, detection and determination of biomolecules. CE with certain configurations has the potential to detect a small number of molecules or even a single molecule, thanks to the high spatial coherence of the laser source which permits the excitation of very small sample volumes with high efficiency. This review article discusses the use of LIF detection for the analysis of peptides and proteins in CE. The most common laser sources, basic instrumentation, derivatization modes and set-ups are briefly presented and special attention is paid to the different fluorogenic agents used for pre-, on- and postcapillary derivatization of the functional groups of these compounds. A table summarizing major applications of these derivatization reactions to the analysis of peptides and proteins in CE-LIF and a bibliography with 184 references are provided which covers papers published to the end of 2005.
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15
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Veledo MT, de Frutos M, Diez-Masa JC. Amino acids determination using capillary electrophoresis with on-capillary derivatization and laser-induced fluorescence detection. J Chromatogr A 2005; 1079:335-43. [PMID: 16038320 DOI: 10.1016/j.chroma.2005.03.111] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Free amino acids have been derivatized on-capillary with 3-(2-furoyl)quinoline-2-carboxaldehyde (FQ) and analyzed using a laboratory-made capillary electrophoresis apparatus with laser-induced fluorescence detection. Several parameters that control on-capillary derivatization of amino acids, including pH, mixing time, reaction time, concentration of the derivatization reagents (potassium cyanide and FQ) and solvent of FQ, as well as the temperature of mixing and reaction were optimized. Repeatabilities better than 1.8% for migration time and 7.8% for peak height were obtained. Assay detection limits for the different amino acids ranged from 23 nM for glycine to 50 nM for lysine and glutamic acid. The methods developed were applied to the analysis of several amino acids in pharmaceutical preparations and plasma samples. Results showed a good agreement with those obtained using an amino acid autoanalyzer for the same samples.
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Affiliation(s)
- Maria Teresa Veledo
- Institute of Organic Chemistry (C.S.I.C.), Juan de la Cierva 3, 28006 Madrid, Spain
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16
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Affiliation(s)
- Mark M Richter
- Department of Chemistry, Southwest Missouri State University, Springfield, Missouri 65804-0089, USA.
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17
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Ye M, Hu S, Quigley WWC, Dovichi NJ. Post-column fluorescence derivatization of proteins and peptides in capillary electrophoresis with a sheath flow reactor and 488 nm argon ion laser excitation. J Chromatogr A 2004; 1022:201-6. [PMID: 14753787 DOI: 10.1016/j.chroma.2003.09.037] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
We report the use of a sheath flow reactor for post-column fluorescence derivatization of proteins. The derivatization reaction employed naphthalene-2,3-dicarboxaldehyde (NDA) and beta-mercaptoethanol, which were added in the sheath buffer. The labeled proteins were detected by laser-induced fluorescence with an argon-ion laser beam at 488 nm. The performance of this detection scheme was evaluated by separation of some protein standards. A column efficiency of 450,000 plates/m was obtained without stacking. The limits of detection for those standard proteins were determined to be from 8 to 32 nM. Excellent linear relationship was obtained with correlation coefficient of 0.9998 for alpha-lactalbumin concentration ranging from 3.91 x 10(-7) to 1.25 x 10(-5) M. Separation of protein standards at low pH was also demonstrated by reversing the electroosmotic flow (EOF) with addition of cetyltrimethylammonium bromide (CTAB) to the running buffer. Different separation selectivity was achieved, but the sensitivity is poorer than that at high pH. This post-column derivatization detection system was applied successfully to analyze the protein extract from HT29 human colon cancer cells as well as tryptic peptides.
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Affiliation(s)
- Mingliang Ye
- Department of Chemistry, University of Washington, Seattle, WA 98915-1700, USA
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19
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García-Campaña AM, Gámiz-Gracia L, Baeyens WRG, Alés Barrero F. Derivatization of biomolecules for chemiluminescent detection in capillary electrophoresis. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 793:49-74. [PMID: 12880854 DOI: 10.1016/s1570-0232(03)00364-7] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
An overview is presented on the power and drawbacks of the relatively unfamiliar chemiluminescence-based detection technique applied in analysis by capillary electrophoresis, for determining chemically derivatized biomolecules. Examples of the most common systems are given for many series of biologically active compounds as well as for some pharmaceuticals. The most common chemiluminescent systems include the application of peroxyoxalate ester chemiluminescence, acridinium esters, luminol and derivatives, detection based on the tris(2,2'-bipyridine)ruthenium(III) system, the huge potentials offered by direct oxidations-though often with still unelucidated reaction mechanisms-and the powerful area of bioluminescence techniques, revealing as well the fast developing area of microchip-based analysis employing this specific luminescence principle.
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Affiliation(s)
- Ana M García-Campaña
- University of Granada, Faculty of Sciences, Department of Analytical Chemistry, Fuentenueva s/n, E-18071, Granada, Spain.
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20
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Abstract
This review gives a short overview of the main approaches to the derivatization of inorganic ions in capillary electrophoresis (CE) with emphasis on the most recent works. Various derivatization procedures and detection methods are discussed. A brief account of their advantages and limitations is given. More specific areas such as microchip CE, simultaneous separation of anions and cations, and speciation analysis are also briefly discussed.
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Affiliation(s)
- Audrius Padarauskas
- Department of Analytical and Environmental Chemistry, Vilnius University, Vilnius, Lithuania.
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21
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Wang X, Wang Q, Chen Y, Han H. Determination of carbohydrates as their 3-aminophthalhydrazide derivatives by capillary zone electrophoresis with on-line chemiluminescence detection. J Chromatogr A 2003; 992:181-91. [PMID: 12735474 DOI: 10.1016/s0021-9673(03)00273-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
A method based on pre-capillary derivatization with luminol (3-aminophthalhydrazide) for carbohydrate analysis using capillary electrophoresis with on-line chemiluminescence (CL) detection was developed. The derivatives of seven monosaccharides were separated and detected by using 200 mM borate buffer containing 100 mM hydrogen peroxide at pH 10.0 as separation electrolyte and 25 mM hexacyanoferrate in 3 M sodium hydroxide solution as post-capillary chemiluminescence reagent with separation efficiencies ranging from 160,000 to 231,000 plates per metre. The minimum amount of carbohydrate derivatized was 2 pmol (corresponding to the concentration of 2 microM). The method also provided a linear response for glucose in the concentration range of 0.1-250 microM with a mass detection limit of 420 amol or a concentration detection limit of 0.1 microM. Preliminary work using the CE-CL format to determine glucose in a rat brain microdialysis sample is presented as a typical case.
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Affiliation(s)
- Xiaoyan Wang
- Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, PO Box 2709, Beijing 100080, China.
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22
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Sze NSK, Huang T, Pawliszyn J. Laser-induced fluorescence detection of non-covalently labeled protein in capillary isoelectric focusing. J Sep Sci 2002. [DOI: 10.1002/1615-9314(20021101)25:15/17<1119::aid-jssc1119>3.0.co;2-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Abstract
Capillary electrophoresis techniques offer high plate numbers and are highly suited for the efficient separations of a wide variety of chemical components in diverse matrices. Because of the small capillary and detection cell dimensions, together with the minute volumes of samples to be injected, sensitive detection schemes based on different physicochemical principles are being developed. One logical approach to increased sensitivity in capillary electrophoresis detection has been the development of chemiluminescence-based detectors. The development of on-line ultrasensitive chemiluminescence detection (referred to the concentration detection limit of nM order of magnitude or mass detection limit of amol order of magnitude) in capillary electrophoresis system is reviewed. The applications and limitations of the current detection methodology are briefly considered and future prospects for the development are discussed.
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Affiliation(s)
- Yan-Ming Liu
- Department of Chemistry, Wuhan University, China
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25
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Yamaguchi M, Yoshida H, Nohta H. Luminol-type chemiluminescence derivatization reagents for liquid chromatography and capillary electrophoresis. J Chromatogr A 2002; 950:1-19. [PMID: 11990983 DOI: 10.1016/s0021-9673(02)00004-3] [Citation(s) in RCA: 90] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The present paper provides the principles for chemiluminescence of luminol-type compounds and their wide and powerful application to the detection system in liquid chromatography and capillary electrophoresis as derivatization reagents. The reagents can be classified into two types, chemiluminescence labeling and chemiluminogenic reagents. The former reagents are highly chemiluminescent themselves and used for tagging their intense chemiluminophores to analytes, whereas the latter are weakly chemiluminescent but generate intense chemiluminescence by reaction with analytes. The liquid chromatographic methods utilizing chemiluminescence derivatizing reactions with luminol-type reagents allow the analytes to be detected at pmol-sub-fmol levels. Furthermore, the chemiluminogenic reactions show high selectivity owing to their selective reaction against the analytes permitting facile and reproducible detection.
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Affiliation(s)
- Masatoshi Yamaguchi
- Faculty of Pharmaceutical Sciences, Fukuoka University, Nanakuma, Johnan, Japan.
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26
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Separation of niobium(V) and tantalum(V) by capillary electrophoresis with chemiluminescence detection. Anal Chim Acta 2001. [DOI: 10.1016/s0003-2670(01)01189-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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27
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Zhan W, Wang T, Li SF. Derivatization, extraction and concentration of amino acids and peptides by using organic/aqueous phases in capillary electrophoresis with fluorescence detection. Electrophoresis 2000; 21:3593-9. [PMID: 11271476 DOI: 10.1002/1522-2683(200011)21:17<3593::aid-elps3593>3.0.co;2-o] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We report a novel method that facilitates sample pretreatment and detection in amino acid analysis by coupling solvent extraction with capillary electrophoresis. Amino acids and peptides were fluorescently labeled, concentrated into an organic solvent, and then separated by capillary zone electrophoresis with fluorescence detection. To achieve this, acetophenone was first employed to dissolve the derivatizing reagent, fluorescamine. The products, which possessed both hydrophilic and hydrophobic moieties, could be extracted and concentrated into the organic phase by suppressing the deprotonation of carboxyl groups, thus enhancing the hydrophobicity of the resulting molecules through pH modification in the aqueous solution. Furthermore, by fine-tuning the pH value, individual amino acids and short peptide molecules could be separated selectively from the sample bulk. This convenient, chemically controllable concentration technique may be useful in sample concentration and purification of biologically related samples such as amino acids and short peptides.
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Affiliation(s)
- W Zhan
- Department of Chemistry, National University of Singapore, Republic of Singapore
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28
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Nagaraj S, Karnes HT. Visible diode laser induced fluorescence detection of doxorubicin in plasma using pressurized capillary electrochromatography. Biomed Chromatogr 2000; 14:234-42. [PMID: 10861734 DOI: 10.1002/1099-0801(200006)14:4<234::aid-bmc973>3.0.co;2-s] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Pressurized capillary electrochromatography is a variant of capillary electrochromatography (CEC) in which the driving force is both electroosmotic and hydraulic. The inlet of the CEC capillary is pressurized using an HPLC pump, and an electric field is simultaneously applied. This work describes a method for the analysis of doxorubicin. Doxorubicin was reacted with Cy5.29.OSu in acetonitrile. The derivative was confirmed by RP-TLC. A CEC system equipped with a VDLIF detector was constructed and used to analyze the derivative. The reaction mixture was injected onto a capillary packed in-house with 3 microm C-18 Luna particles and separation was carried out at 25 kV using 70% acetonitrile/ 30% phosphate (10 mM, pH = 4.8) as the mobile phase. The derivatization reaction was optimized by the investigation of parameters such as reaction time, temperature and concentration of label in order to increase the yield of the derivative. The optimal conditions were determined to be 30 min, 80 degrees C and 50 nmol/mL, respectively. Doxorubicin was extracted from plasma using solid-phase extraction under alkaline conditions, derivatized and injected onto the CEC-VDLIF system. The selectivity of the assay was demonstrated by a lack of interfering peaks due to plasma constituents across the elution window of the derivative peak in blank plasma extracts (n = 6 sources). The limit of detection (LOD) of the assay in plasma calculated as 3 s(b)/m was determined to be 1.7 ng/mL. The precision of the assay determined at a concentration of 167.7 ng/mL (n = 5) was found to be within 7.04 %RSD.
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Affiliation(s)
- S Nagaraj
- Department of Pharmaceutics, Virginia Commonwealth University, PO Box 980533, Richmond, VA 23298-0533, USA
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Carabias-Martínez R, Rodríguez-Gonzalo E, Domínguez-Alvarez J, Hernandez-Méndez J. Determination of triazine herbicides in natural waters by solid-phase extraction and non-aqueous capillary zone electrophoresis. J Chromatogr A 2000; 869:451-61. [PMID: 10720258 DOI: 10.1016/s0021-9673(99)01273-x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Capillary zone electrophoresis (CZE) in an organic medium was used to analyse triazines at sub-ppb concentration levels in natural waters after a preconcentration step using conventional C18 cartridges and new Oasis HLB devices. With both sorbents, satisfactory results were obtained on analysing deionized water. However, on analysing natural waters, both sorbents showed very different types of behaviour. The different variables affecting the elution of both sorbents were studied, resulting in the choice of Oasis HLB as the most suitable for later separation by CZE in non-aqueous medium. Combination of a preconcentration step with electrokinetic injection revealed that capillary electrophoresis with simple UV detection can also be used satisfactorily for the quantification of micropollutants in natural waters. The detection limits obtained varied between 0.01 and 0.05 microg l(-1), depending on the type of matrix analysed. The day-to-day precision varied between 0.9% and 2.3%, expressed as the relative standard deviation.
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Affiliation(s)
- R Carabias-Martínez
- Departamento de Química Analítica Nutrición y Bromatología, Facultad de Química, Universidad de Salamanca, Spain.
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