Method Improvement for Detection of ∆9-Tetrahydrocannabinol in Hair

Sarah Glenn and Dr. Godfrey

Current testing for marijuana usage is done using urine or blood analysis. These analytical methods are useful in determining current or recent use of marijuana but have a limited window of viability. The difficulty with current hair analysis techniques is the lengthy time needed for sample preparation, which includes washing, drying, a hair size reduction technique, and digestion. This initial research has worked to reduce preparation time needed from 2 days to 2-5 hours, making hair analysis more accessible for the backlogged forensic laboratories.

Results have shown that there is not a significant difference in the quantity of 11-nor-9-carboxy-tetrahydrocannabinol, one of the main metabolites of tetrahydrocannabinol or THC, detected using the both the original way to prepare hair and the new technique for preparing hair. The different methods had an average concentration of 600 ng/ml +/- 50 ng/mL. The time savings offered by these methods could result in an increase in hair analysis in forensic laboratories across the United States.