Combined high-performance liquid chromatography and radioimmunoassay method for the analysis of delta 9-tetrahydrocannabinol metabolites in human urine.

A high-performance liquid chromatography-radioimmunoassay method for the measurement of cannabinoids in urine is described. The method involves chromatographing a hydrolysed urine sample with high-performance liquid chromatography and quantifying the eluting cross-reacting cannabinoids with radioimmunoassay. It has been applied to the analysis of cannabinoids in human urine obtained from subjects who had smoked delta 9-tetrahydrocannabinol and the identities of some of the cross-reacting cannabinoids have been established by gas chromatography-mass spectrometry. The method is suitable for use as a routine procedure for cannabinoid analysis in urine.