HPLC determination of cocaine and benzoylecgonine in plasma and urine from drug abusers.
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.
Fernández
P
P
Department of Legal Medicine, Faculty of Medicine, University of Santiago de Compostela, Spain.
Lafuente
N
N
Bermejo
A M
AM
López-Rivadulla
M
M
Cruz
A
A
D002851:Chromatography, High Pressure Liquid; D003042:Cocaine / Q000031:analogs & derivatives* / Q000097:blood* / Q000652:urine*; D006801:Humans; D019966:Substance-Related Disorders / Q000097:blood* / Q000652:urine*
C005618:benzoylecgonine; D003042:Cocaine