Detection of 11-nor-9-carboxy-tetrahydrocannabinol in the hair of drug abusers by LC-MSMS analysis.
Cannabis is the second most commonly abused illicit drug after methamphetamine in South Korea. To prove cannabis consumption, 11-nor-9-carboxy-tetrahydrocannabinol (THC-COOH), the metabolite of tetrahydrocannabinol (THC), was screened for in a hair analysis. In this study, we developed a liquid chromatography-tandem mass spectrometry (LC-MSMS) analysis method, which was used to analyze authentic hair samples in 2017. Possible contaminants on the surface of hair samples were eliminated by washing twice each with 2mL of methanol and distilled water. After adding an internal standard (THC-COOH-d