Confirmation of Emit Cannabinoid Assay Results by Bonded Phase Adsorption with Thin Layer Chromatography

Abstract
Clinical urine specimens were screened for the presence of cannabinoids [constituents of marijuana, a drug of abuse] using the EMIT Cannabinoid Assay. Aliquots of these samples were also analyzed for 11-nor-.DELTA.9-tetrahydrocannabinol-9-carboxylic acid (THCA), the major cannabis metabolite in urine, by a technique which combines bonded phase adsorption (BPA) and TLC. A 100% agreement between EMIT and BPA-TLC results was observed when at least 20 ml of urine was assayed by BPA-TLC. Bonded phase adsorption coupled with TLC appears to be a suitable technique for the confirmation of positive EMIT Cannabinoid Assay results.