Current role of capillary electrophoretic/electrokinetic techniques in forensic toxicology (original) (raw)
Related papers
Forensic Science International, 1995
Capillary electrophoresis, the modern approach to instrumental electrophoresis, is probably the most rapidly expanding analytical t~hnique that has appeared in recent years. In the hands of forensic toxicologists, capillary electrophoresis (CE) represents a powerful new analytical tool, which has proved suitable for the investigation of illicit drugs in seized preparations and also in complex biological matrices, among which is hair. CE can be applied according to different separation mechanisms, and among those that are toxicologically relevant are capillary zone el~~ophor~is and micellar eiectrokinetic capillary c~o~to~phy, which display different selectivities. For the investigation of hair for drugs of abuse, capillary electrophoresis proved effective, providing simultaneous determinations of different drugs without derivatixation, with acceptable sensitivity (typically better than 1 ng of drug per mg of hair). The possibility of carrying out determinations of the same analytes, based on different separation mechanisms (capillary zone electrophoresis and micellar eleetrokinetic chromatography) with the same ins~en~tion, simply changing the buffer composition, provides an interesting possibility of 'internal' contirmation of the results.
Capillary Electrophoresis in Forensic Chemistry
Encyclopedia of Forensic Sciences, 2013
This article was originally published in Encyclopedia of Forensic Sciences, Second Edition published by Elsevier, and the attached copy is provided by Elsevier for the author's benefit and for the benefit of the author's institution, for non-commercial research and educational use including without limitation use in instruction at your institution, sending it to specific colleagues who you know, and providing a copy to your institution's administrator.
Capillary electrophoresis: principles and applications in illicit drug analysis
Forensic Science International, 1996
Capillary electrophoresis, which appeared in the early 198Os, is now rapidly expanding into many scientific disciplines. including analytical chemistry. biotechnology and biomedical and pharmaceutical sciences. In capillary electrophoresis. electrokinetic separations are carried out in tiny capillaries at high voltages (lo-30 kV). thus obtaining high efficiencies (,li > 105) and excellent mass sensitivities (down to 10 Ix-10 "I moles). The main features of capillary electrophoresis are: versatility of application (from inorganic ions to large DNA fragments), use of different separation modes with different selectivity. extremely low demands on sample volume, negligible running costs, possibility of interfacing with different detection systems, ruggedness and simplicity of instrumentation. Capillary electrophoresis applications in forensic sciences have appeared only recently. but are now rapidly growing, particularly in forensic toxicology. The present paper briefly describes the basic principles of capillary electrophoresis, from both the instrumental and analytical points of view. Furthermore. the main applications in the analysis of illicit,controlled drugs in both illicit preparations and biological samples are presented and discussed (43 references).
Journal of Chromatography A, 1996
The purpose of this work was to compare different CE separation modes, namely capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MECC), for the analysis of drugs of forensic interest in order to assess the mutual degree of independence and consequently the possibility of complementary use for mutual confirmation of results. A panel of drugs including caffeine, morphine, barbital, pentobarbital, codeine, nalorphine, lidocaine, procaine, heroin, flunitrazepam, acetylcodeine, papaverine, amphetamine, narcotine, cocaine, diazepam, tetracaine, narceine, 6-monoacetylmorphine acetylcodeine and thebaine, were separated according to a MECC and two CZE methods. The MECC separation was carried out in a bare silica capillary (50/xm I.D.) with a buffer composed of 25 mM borate (pH 9.24)-20% methanol-100 mM sodium dodecyl sulphate; the applied voltage was 20 kV. The first CZE method (CZE1) was carried out in 50 mM phosphate buffer (pH 2.35) at 20 kV with a bare silica capillary (50/xm I.D.), and the second (CZE2) with 50 mM borate (pH 9.24) at 12 kV with the same capillary. The three methods were effective in the separation of the test drug mixture, but MECC was the only able to resolve all the components. Relative (to flunitrazepam) migration time RSDs ranged from 0.3 to 2.8% for MECC, from 0.1 to 1.4% for CZE1 and from <0.1 to 0.5% for CZE2. The separation patterns (migration order) of the three methods were compared with Spearman's test and with principal component analysis. CZE1 and CZE2 were significantly and directly correlated (r = 0.749, p < 0.002), whereas MECC and CZE2 were also significantly, but inversely correlated (r=-0.865, p<0.001). MECC and CZE1 (limitedly to the basic drugs) appeared non-correlated (r = -0.131, p = 0.630) and therefore the two techniques are suitable for combined use to increase the discriminatory power.
Journal of The Brazilian Chemical Society, 2003
Desde sua implementação na década de 80, a eletroforese capilar vem evoluindo, tornando-se uma técnica de separação bem estabelecida e, hoje, engloba de fato, uma família de técnicas eletrocinéticas, com mecanismos de separação distintos e seletividade característica, todas passíveis de serem conduzidas em uma única coluna capilar. Neste trabalho, a versatilidade da eletroforese capilar para lidar com materiais de diferentes classes químicas e matrizes complexas é ilustrada, apresentando aplicações representativas nas áreas clínica, forense, cosmética, ambiental, nutricional e farmacêutica, compilando os interesses de pesquisa e resultados do nosso próprio grupo.
Capillary Electrophoresis Coupled To Mass Spectrometry for Forensic Analysis
The Open Chemical Engineering Journal, 2007
In this review the most important techniques, which are developed to hyphenate capillary electrophoresis to mass spectrometry (CE-MS), suitable for forensic analysis, are summarized. Analytes of interest are divided into four main parts, namely, compounds with amine containing side chains, compounds with N-containing saturated ring structures, other heterocycles and peptides. Sample pre-treatments and direct injection modes used in CE-MS for forensic analysis are briefly discussed from critical point of view. Special emphasis is placed to point out the advantages of mass spectrometric detection compared to UV-and laser-induced fluorescence (LIF) detections.