Department of Medicine, Section of Clinical Pharmacology, Karolinska Institutet, Stockholm, Sweden.
J Anal Toxicol. 2011 Oct;35(8):541-4. doi: 10.1093/anatox/35.8.541.
Exhaled breath has recently been proposed as a new possible matrix for drugs of abuse testing. A key drug is cannabis, and the present study was aimed at investigating the possibility of detecting tetrahydrocannabinol and tetrahydrocannabinol carboxylic acid in exhaled breath after cannabis smoking. Exhaled breath was sampled from 10 regular cannabis users and 8 controls by directing the exhaled breath by suction through an Empore C(18) disk. The disk was extracted with hexane/ethyl acetate, and the resulting extract was evaporated to dryness and redissolved in 100 μL hexane/ethyl acetate. A 3-μL aliquot was injected onto the LC-MS-MS system and analyzed using positive electrospray ionization and selected reaction monitoring. In samples collected 1-12 h after cannabis smoking, tetrahydrocannabinol was detected in all 10 subjects. The rate of excretion was between 9.0 and 77.3 pg/min. Identification of tetrahydrocannabinol was based on correct retention time relative to tetrahydrocannabinol-d(3) and correct product ion ratio. In three samples, peaks were observed for tetrahydrocannabinol carboxylic acid, but these did not fulfill identification criteria. Neither tetrahydrocannabinol or tetrahydrocannabinol carboxylic acid was detected in the controls. These results confirm older reports that tetrahydrocannabinol is present in exhaled breath following cannabis smoking and extend the detection time from minutes to hours. The results further support the idea that exhaled breath is a promising matrix for drugs-of-abuse testing.
呼气已被最近提出作为药物滥用测试的一个新的可能的基质。一种关键药物是大麻，本研究旨在调查在吸食大麻后检测呼气中四氢大麻酚和四氢大麻酚羧酸的可能性。通过抽吸将呼出的气体引导通过 Empore C(18)圆盘从 10 名常规大麻使用者和 8 名对照者中采集呼气。用正己烷/乙酸乙酯提取圆盘，将得到的提取物蒸发至干燥并重新溶解在 100 μL 正己烷/乙酸乙酯中。取 3 μL 等分试样注入 LC-MS-MS 系统，并使用正电喷雾电离和选择反应监测进行分析。在吸食大麻后 1-12 小时采集的样品中，在所有 10 名受试者中均检测到四氢大麻酚。排泄率在 9.0 至 77.3 pg/min 之间。四氢大麻酚的鉴定基于与四氢大麻酚-d(3)的正确保留时间和正确的产物离子比。在三个样本中，观察到四氢大麻酚羧酸的峰，但这些峰未满足鉴定标准。对照者中未检测到四氢大麻酚或四氢大麻酚羧酸。这些结果证实了较早的报告，即吸食大麻后，四氢大麻酚存在于呼气中，并将检测时间从分钟延长至小时。结果进一步支持呼气是药物滥用测试的一个有前途的基质的观点。
