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영어

Cannabis is strictly regulated under the Narcotics Control Act in Korea. Urine and hair samples are commonly used as biological samples to prove cannabis abuse. In general, to determine whether cannabis has been abused, 11-nor-9-carboxy -tetrahydrocannabinol (Δ9-THC-COOH), a major metabolite of cannabis, is analyzed to rule out the possibility of external contamination. Recently, 11-nor-8-tetrahydrocannabinol (Δ8-THC), an isomer of 11-nor-9-tetrahydrocannabinol (Δ9-THC) synthesized with cannabidiol (CBD), has also been abused in the form of electronic cigarettes, and its metabolite is 11-nor-8-carboxytetrahydrocannabinol (Δ8-THC-COOH). We attempted to analyze these cannabis metabolites in the nails to determine whether the subjects smoked cannabis. Method validation was performed using a Sciex 6500 LC/MS/MS for Δ8-THC-COOH and Δ 9-THC-COOH (THC-COOHs) in nails. The instrument conditions for THC-COOHs analysis were the same as those used for hair analysis, a column switching LC–ESI-MS 3 method. THC-COOHs were extracted by liquid-liquid extraction from digested nails with 1 N NaOH. The quantification of THC-COOHs and the identification of THC-COOH-d3 were performed using multistage fragmentation (MS3) with two transitions for THC-COOHs (m/z 343.1→299.1→245.2 and m/z 343.1→299.1→191.1) and one transition for THC-COOH- d3 (m/z 346.1→302.2→248.1). The quantifier ions are m/z 245.2 and 248.1. The calibration curve ranged from 0.05 to 20 pg/mg, R2 exceeded 0.999, and the LOD and LOQ of both components were 0.05 and 0.1 pg/mg, respectively. The accuracy and precision, matrix effect, recovery, and process efficiency were all within 15% of the CV values. Method validation results for THC-COOHs analysis for nails were not significantly different from those of hair, including the LOD and LOQ results. (Table 4.) Only one of the three authentic nail samples showed a positive result for Δ9-THC-COOH at a concentration of 12.29 pg/mg. These results indicate that since nails and hair can be analyzed under similar conditions, they may be useful alternatives to each other when collecting evidence of cannabis abuse.