가스크로마토그라피/질량분석기에 의한 모발중 대마(大麻)성분 분석

Analysis of Δ9-Tetrahydrocannabinol and 11-nor-9-carboxytetrahydrocannabinol in Hair by Gas Chromatography/Mass Spectrometry

An analytic method was developed for the quantitation of Δ9- tetrahydrocannabinol (THC) and 11-nor-9-carboxy THC (THC-COOH) in human hair. After hair samples were pulverized using Freezer Mill, deuterated internal standards were added and digested in 1 N NaOH at 100℃ water bath for 30 min. Digest solutions were extracted by 5 ml hexane : ethyl acetate (90 : 10) after acidification with acetic acid. The organic phase was evaporated under N2 and deriva- tized by BSTFA (with 1% TMCS) at 85℃ for 45 min. The derivatized solution was separated on HP-5MS column (30 m×O.25 mm×0.25 um) and detected using EI-GC-MS with selective ion monitoring mode. The assay of calibration was ranged from 5 to 100 ng/50 mg hair (r2>0.99) for THC and THC-COOH. Within and between-run precision were calculated at 6,30,60 ng/50 mg hair with coefficients of variation less than 11%. Within and between run accuracies at the same concentrations were ± 14% and ±30% of target for both analyses, respectively. Absolute and relative recovery at 10 and 100 ng were 60~91%. The method was used to detect and quantify THC and THC-COOH in cannabis abuser's halers (N=16) and SRM (N=5, THC 1 ng/mg, NIST). We detected THC and THC-COOH in only one hair sample. In SRM, % accuracy was 93% (range 86~103%) and precision (% CV) was 8.14. We began to set up a quantitative analysis of THC and THC-COOH using EI-GC-MS. Continuously, we need to modify and develop this method in order to apply for identification in cannanbis users' hair.