Application of solid-phase micro-extraction technology to drug screening and identification

Benzodiazepines, tricyclic antidepressants and local anaesthetics are frequ ently involved in poisoning episodes and fatalities. A specific, sensitive and rapid procedure for identifying and quantifying such drugs in postmorte m matrices has been developed using solid-phase micro-extraction (SPME) and gas chromatography-mass spectrometry. Very clean extracts were obtained in one step using SPME. The most commonly used fibre coatings were tested to select the best coating for SPME of the drugs. The appropriate fibre coatin g for most drugs was polyacrylate, followed by Carbowax-divinylbenzene. A H ewlett-Packard 5890 gas chromatograph in combination with a Trio 2000 mass spectrometer was used to analyse the samples. Temperature, time, pH and add ition of sodium chloride were optimized to obtain consistent extraction. Th e between-day and within-day coefficients of variation were less than 16% a nd less than 6%, respectively.