title: Analysis of cocaine and three of its metabolites in hair by gas chromatography-mass spectrometry using ion-trap detection for CI/MS/MS.
abstract: A sensitive GC/CI/MS/MS method was developed for the simultaneous determination of cocaine (COC), anhydroecgonine methylester (cocaine pyrolysis product, AEME), ecgonine methylester (cocaine enzymatic hydrolysis product, EME) and cocaethylene (cocaine with ethanol trans-esterification product, COET) in human hair samples. After acid hydrolysis, hair samples were extracted with an automated solid phase extraction (SPE). The analysis of cocaine and its three metabolites was performed using an ion-trap spectrometer in positive chemical ionization with isobutane as gas reagent. The procedure was validated. Weighted linear regression was found appropriate in a concentration range of 0.10-5.00 ng/mg for AEME, 0.05-5.00 ng/mg for COC, EME and COET. The limit of detection was estimated at 0.005 ng/mg for COC and COET, at 0.025 ng/mg for EME, and at 0.050 ng/mg for AEME. Method performance was evaluated in terms of trueness and precision using quality control (QC) samples over the investigated ranges. Method selectivity and robustness were also demonstrated.
authors.affiliation: Institute of Forensic Medicine, University of Geneva, 9 Avenue de Champel, 1211 Geneva 4, Switzerland.
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Cognard
authors.forename: Serge
authors.initials: S
authors.lastname: Rudaz
authors.forename: Stéphane
authors.initials: S
authors.lastname: Bouchonnet
authors.forename: Christian
authors.initials: C
authors.lastname: Staub
mesh_terms: D000293:Adolescent; D000328:Adult; D002138:Calibration; D003042:Cocaine / Q000031:analogs & derivatives / Q000032:analysis* / Q000378:metabolism*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods*; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: C068464:anhydroecgonine methyl ester; C066444:cocaethylene; D003042:Cocaine; C034524:ecgonine methyl ester