Toxicological drug screening by overpressured layer chromatography

Two overpressured layer chromatography (OPLC) systems were developed for th e screening of toxicologically relevant basic drugs in forensic and clinica l contexts. The OPLC1 system was trichloroethylene - methylethylketone - n- butanol - acetic acid water 17+8+25+6+4 and the OPLC2 system was butyl acet ate ethanol - tripropylamine - water 85+9.25+5+0.75 with presaturation. Bot h systems were tested on high performance silica gel plates. The Rf values of the drugs were reproducible, the peak shapes were symmetrical, and the c hromatographic systems showed low mutual correlation (r = 0.103). The separ ation numbers (SN) were 27.5 and 29.2 for OPLC1 and OPLC2, respectively, wh ich are more than two times higher than those obtained with TLC systems in general. The combination of the systems was demonstrated to be feasible in the screening for drugs in autopsy urine samples, utilizing automated ident ification by hR(f)(c)/UV library search with combined dual-system reporting .