Automated Extraction of Direct, Reactive, and Vat Dyes from Cellulosic Fibers for Forensic Analysis by Capillary Electrophoresis
Department
Chemistry and Biochemistry
Document Type
Article
Publication Date
6-18-2009
Abstract
Systematic designed experiments were employed to find the optimum conditions for extraction of direct, reactive, and vat dyes from cotton fibers prior to forensic characterization. Automated microextractions were coupled with measurements of extraction efficiencies on a microplate reader UV–visible spectrophotometer to enable rapid screening of extraction efficiency as a function of solvent composition. Solvent extraction conditions were also developed to be compatible with subsequent forensic characterization of extracted dyes by capillary electrophoresis with UV–visible diode array detection. The capillary electrophoresis electrolyte successfully used in this work consists of 5 mM ammonium acetate in 40:60 acetonitrile–water at pH 9.3, with the addition of sodium dithionite reducing agent to facilitate analysis of vat dyes. The ultimate goal of these research efforts is enhanced discrimination of trace fiber evidence by analysis of extracted dyes.
Journal Title
Analytical and Bioanalytical Chemistry
Journal ISSN
1618-2642
Volume
394
Issue
8
First Page
2095
Last Page
2103
Digital Object Identifier (DOI)
10.1007/s00216-009-2876-8