A novel 125I radioimmunoassay for the analysis of delta 9-tetrahydrocannabinol and its metabolites in human body fluids.

A cannabinoid radioimmunoassay (RIA) that detects some of the major delta 9-THC metabolites is developed and evaluated for use in forensic science. It incorporates a novel 125I radiotracer, is sensitive, reliable, relatively quick, and simple to use. The RIA uses a commercially available antiserum and detects a number of cannabinoid metabolites, including delta 9-THC-11-oic acid and its glucuronide conjugate in biological fluids. The method was successfully applied to the analysis of blood and urine samples submitted for forensic analysis.