Determination of delta 1-tetrahydrocannabinol in human fat biopsies from marihuana users by gas chromatography-mass spectrometry.
A gas chromatographic-mass spectrometric (GC/MS) method for analysis of delta 1-tetrahydrocannabinol (delta 1-THC) in human fat samples is described. The fat sample, obtained from heavy marihuana users 1 week before and 4 weeks after smoking, is homogenized in hexane + 2-propanol, centrifuged, and the supernatant mixed with Lipidex 5000. The solvent is evaporated and the dried gel is packed in a glass column. delta 1-THC is eluted from the column with methanol + water + acetic acid, diluted with water and the eluent is passed through a bed of Octadecylsilane-bonded silica. After washing and drying, the retained delta 1-THC is eluted with hexane, derivatized with N-methyl-N-(t-butyl-dimethysilyl)trifluoroacetamide (MTBSTFA) and finally purified by HPLC on an Octadecyl Sl 100 column in methanol. The amount of delta 1-THC is determined by GC/MS, using selected ion monitoring, and a deuterated internal standard. The recovery of delta 1-THC is about 80%, and the concentration of delta 1-THC in the fat samples analysed ranged between 0.4 and 193 ng/g wet tissue.
Johansson
E
E
Department of Pharmacognosy, Uppsala University, Sweden.
Norén
K
K
Sjövall
J
J
Halldin
M M
MM
D000273:Adipose Tissue / Q000032:analysis*; D001706:Biopsy; D002851:Chromatography, High Pressure Liquid; D013759:Dronabinol / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000378:metabolism*
D013759:Dronabinol