Welch M J, Sniegoski L T, Allgood C C, Habram M
Organic Analytical Research Division, National Institute of Standards and Technology, Gaithersburg, MD 20899.
J Anal Toxicol. 1993 Nov-Dec;17(7):389-98. doi: 10.1093/jat/17.7.389.
Methods for extraction of cocaine, some of its metabolites, morphine, and codeine from hair and methods for analyzing the extracts have been investigated. Results of these studies have shown that extractions with 0.1N HCl are efficient at removing the target compounds from hair and appear to be as effective as enzymatic digestions that dissolve the hair. GC/MS with either electron ionization or chemical ionization was found to provide accurate and unambiguous determinations of the target compounds. Tandem mass spectrometry (MS/MS) also provided accurate results when performed on extracts from hair, but results were ambiguous when MS/MS was performed on hair segments directly. Environmental issues, including the removal of powdered and vapor-deposited cocaine from the hair surface and the effect of various hair treatments on the levels of cocaine entrapped in hair, have also been investigated. Removal of cocaine deposited on hair was incomplete by all approaches tested, making differentiation of hair of cocaine users from hair with environmental exposure of cocaine difficult. Cocaethylene, a cocaine metabolite believed to be formed in the liver, was found in the hair of some cocaine users and may be a good marker for proving drug use. Common hair treatments, such as shampoos, conditioners, and peroxide bleaches, reduced cocaine levels in a fortified hair material by 60 to 80% after 30 treatments. Finally, to assist laboratories in evaluating the accuracy of their methods, two human hair reference materials with recommended concentrations of cocaine, benzoylecgonine, morphine, and codeine determined by GC/MS have been developed.
对从毛发中提取可卡因及其某些代谢物、吗啡和可待因的方法以及提取物的分析方法进行了研究。这些研究结果表明，用0.1N盐酸提取能有效地从毛发中去除目标化合物，并且似乎与溶解毛发的酶消化法一样有效。发现采用电子电离或化学电离的气相色谱/质谱联用技术能够准确无误地测定目标化合物。对毛发提取物进行串联质谱分析（MS/MS）时也能得到准确结果，但直接对毛发片段进行MS/MS分析时结果不明确。还研究了环境问题，包括从毛发表面去除粉末状和气相沉积的可卡因以及各种毛发处理对毛发中截留的可卡因水平的影响。通过所有测试方法去除沉积在毛发上的可卡因均不完全，这使得区分可卡因使用者的毛发和受环境可卡因暴露影响的毛发变得困难。在一些可卡因使用者的毛发中发现了一种据信在肝脏中形成的可卡因代谢物——乙基苯甲酰芽子碱，它可能是证明吸毒的一个良好标志物。常见的毛发处理，如洗发水、护发素和过氧化物漂白剂，在对强化毛发材料进行30次处理后，可使其中的可卡因水平降低60%至80%。最后，为协助实验室评估其方法的准确性，已开发出两种人发标准物质，通过气相色谱/质谱联用技术测定了其中可卡因、苯甲酰芽子碱、吗啡和可待因的推荐浓度。
