Chromatographic screening techniques in systematic toxicological analysis

A review of techniques used to screen biological specimens for the presence of drugs was conducted with particular reference to systematic toxicologic al analysis. Extraction systems of both the liquid-liquid and solid-phase t ype show little apparent difference in their relative ability to extract a range of drugs according to their physio-chemical properties, although mixe d-phase SPE extraction is a preferred technique for GC-based applications, and liquid-liquid were preferred for HPLC-based applications. No one chroma tographic system has been shown to be capable of detecting a full range of common drugs of abuse, and common ethical drugs, hence two or more assays a re required for laboratories wishing to cover a reasonably comprehensive ra nge of drugs of toxicological significance. While immunoassays are invariab ly used to screen for drugs of abuse, chromatographic systems relying on de rivatization and capable of extracting both acidic and basic drugs would be capable of screening a limited range of targeted drugs. Drugs most difficu lt to detect in systematic toxicological analysis include LSD, psilocin, TH C and its metabolites, fentanyl and its designer derivatives, some potent o piates, potent benzodiazepines and some potent neuroleptics, many of the ne wer anti-convulsants, alkaloids colchicine, amantins, aflatoxins, antineopl astics, coumarin-based anti-coagulants, and a number of cardiovascular drug s. The widespread use of LC-MS and LC-MS-MS for specific drug detection and the emergence of capillary electrophoresis linked to MS and MS-MS provide an exciting possibility for the future to increase the range of drugs detec ted in any one chromatographic screening system. (C) 1999 Elsevier Science BN. All rights reserved.