SIMULTANEOUS SOLID-PHASE EXTRACTION ON C-18 CARTRIDGES OF OPIATES ANDCOCAINICS FOR AN IMPROVED QUANTITATION IN HUMAN HAIR BY GC-MS - ONE-YEAR OF FORENSIC APPLICATIONS

We have developed a new solid-phase extraction (SPE) on C-18 cartridge s which allows a very simple protocol of manipulation and a single elu tion of opiates and cocainics from human hair samples. The method invo lved decontamination in a phosphate buffer and dichloromethane, pulver ization in a ball mill, addition of deuterated internal standards, hea ted acid hydrolysis and SPE, Quantitation utilized gas chromatography and mass spectrometry. Between days precise study gave relative standa rd deviations always inferior to 8.9% for each compound at 4 ng/mg (ex cept methylecgonine ester=15.7%). Accuracy was tested using a I-statis tic versus a reference material from the NIST. Limits of detection wer e calculated from an analysis of the blanks which contained between 0. 12 and 0.28 ng/mg for each drug. The method was applied in forensic ca ses for 1 year of toxicological activity. Among the 108 analyses perfo rmed, 30 were positive for cocaine and 33 for opiates. Concentrations were in the range 0.9-242.0 ng/mg (cocaine), 0.3-71.3 ng/mg (benzoylec gonine), 0.0-9.8 ng/mg (methylecgonine ester), 0.0-2.9 ng/mg (cocaethy lene), 0.1-11.5 ng/mg (codeine), 0.4-44.6 ng/mg (morphine) and 0.7-131 .2 ng/mg (6-acetylmorphine). Ratios of the metabolites to parent drugs were proposed to avoid risk of external contamination. (C) 1997 Elsev ier Science Ireland Ltd.