delta-9-Tetrahydrocannabinol analysis in forensic blood specimens using capillary column gas chromatography with nitrogen sensitive detection.

A method for the determination of delta-9-tetrahydrocannabinol (THC) in whole blood that employs hexane extraction followed by identification using gas chromatography with nitrogen/phosphorus detection has been developed. The assay is sensitive to 2 ng THC per mL blood and linear to concentrations up to 120 ng/mL (r = 0.998). Precision is demonstrated by coefficients of variation ranging from 3.6 to 9.1% (within run) and 7.1 to 8.0% (between run).