title: HPLC determination of cocaine and benzoylecgonine in plasma and urine from drug abusers.
abstract: Reversed-phase high-performance liquid chromatography (HPLC) was used for the determination of cocaine and its metabolite, benzoylecgonine (BZE), in plasma and urine. Following a solid-liquid extraction with Bond-Elut Certify cartridges and using methaqualone as reference compound, chromatography was performed with a Lichrospher RP 18 (125 x 4-mm i.d.) reversed-phase column, ultraviolet (UV) detection at 235 nm, and methanol (pH 7)-phosphate buffer (70:30 v/v) as mobile phase. Linearity was obtained from 0.1 to 20 micrograms/mL with a good correlation coefficient. Recoveries ranged from 76.9 to 96.5%, and coefficients of variation were always less than 5.0%. Urine samples from live, cocaine-intoxicated patients contained concentrations of 0.21-75.55 micrograms/mL BZE and less than 4.14 micrograms/mL cocaine, whereas postmortem urine analyses gave concentrations of 5.86-198.76 micrograms/mL for BZE and 1.56-33.24 micrograms/mL for its parent compound. Finally, postmortem blood samples were all negative for cocaine and gave BZE concentrations of 0.040-0.53 micrograms/mL.
authors.affiliation: Department of Legal Medicine, Faculty of Medicine, University of Santiago de Compostela, Spain.
authors.forename: P
authors.initials: P
authors.lastname: Fernández
authors.forename: N
authors.initials: N
authors.lastname: Lafuente
authors.forename: A M
authors.initials: AM
authors.lastname: Bermejo
authors.forename: M
authors.initials: M
authors.lastname: López-Rivadulla
authors.forename: A
authors.initials: A
authors.lastname: Cruz
mesh_terms: D002851:Chromatography, High Pressure Liquid; D003042:Cocaine / Q000031:analogs & derivatives* / Q000097:blood* / Q000652:urine*; D006801:Humans; D019966:Substance-Related Disorders / Q000097:blood* / Q000652:urine*
chemical_list: C005618:benzoylecgonine; D003042:Cocaine