Screening and confirmation of opiates by thin-layer chromatography.

A thin-layer chromatography (TLC) procedure for the screening and confirmation of urinary codeine and morphine has been developed. Urine samples are hydrolyzed to liberate free codeine and morphine, extracted into an organic solvent, and concentrated. For screening, the extraction residues are spotted on TLC plates which are developed in chloroform:ethyl acetate:methanol:propylamine (35:45:5:5). For confirmation, the extraction residues are acetylated and then spotted on TLC plates which are developed in hexane:chloroform:diethylamine (50:30:7). The spots for the two drugs are visualized with acidified iodoplatinate. Codeine and morphine are well separated from one another and from normal urinary substances on both plates and can be detected at a concentration of 0.4 micrograms/mL.