Smith Michael L, Nichols Daniel C, Underwood Paula, Fuller Zachary, Moser Matthew A, Flegel Ron, Gorelick David A, Newmeyer Matthew N, Concheiro Marta, Huestis Marilyn A
U.S. Army Forensic Toxicology Drug Testing Laboratory, Fort Meade, MD, USA.
Division of Workplace Programs, Department of Health and Human Services, Substance Abuse Mental Health Services Administration, Rockville, MD, USA.
J Anal Toxicol. 2014 Oct;38(8):524-7. doi: 10.1093/jat/bku077.
Legitimate use of legal intranasal decongestants containing l-methamphetamine may complicate interpretation of urine drug tests positive for amphetamines. Our study hypotheses were that commonly used immunoassays would produce no false-positive results and a recently developed enantiomer-specific gas chromatography-mass spectrometry (GC-MS) procedure would find no d-amphetamine or d-methamphetamine in urine following controlled Vicks VapoInhaler administration at manufacturer's recommended doses. To evaluate these hypotheses, 22 healthy adults were each administered one dose (two inhalations in each nostril) of a Vicks VapoInhaler every 2 h for 10 h on Day 1 (six doses), followed by a single dose on Day 2. Every urine specimen was collected as an individual void for 32 h after the first dose and assayed for d- and l-amphetamines specific isomers with a GC-MS method with >99% purity of R-(-)-α-methoxy-α-(trifluoromethyl)phenylacetyl derivatives and 10 µg/L lower limits of quantification. No d-methamphetamine or d-amphetamine was detected in any urine specimen by GC-MS. The median l-methamphetamine maximum concentration was 62.8 µg/L (range: 11.0-1,440). Only two subjects had detectable l-amphetamine, with maximum concentrations coinciding with l-methamphetamine peak levels, and always ≤ 4% of the parent's maximum. Three commercial immunoassays for amphetamines EMIT(®) II Plus, KIMS(®) II and DRI(®) had sensitivities, specificities and efficiencies of 100, 97.8, 97.8; 100, 99.6, 99.6 and 100, 100, 100%, respectively. The immunoassays had high efficiencies, but our first hypothesis was not affirmed. The EMIT(®) II Plus assay produced 2.2% false-positive results, requiring an enantiomer-specific confirmation.
合法使用含l-甲基苯丙胺的合法鼻用减充血剂可能会使尿药检中苯丙胺呈阳性的结果难以解释。我们的研究假设是，常用的免疫分析法不会产生假阳性结果，并且一种最近开发的对映体特异性气相色谱-质谱法（GC-MS）在按照制造商推荐剂量使用Vicks VapoInhaler进行对照给药后，在尿液中不会检测到d-苯丙胺或d-甲基苯丙胺。为了评估这些假设，22名健康成年人在第1天每2小时服用一剂（每侧鼻孔吸入两次）Vicks VapoInhaler，持续10小时（六剂），然后在第2天服用一剂。在首次给药后32小时内，每次尿液样本均作为单独的一次排尿收集，并采用GC-MS方法检测d-和l-苯丙胺的特定异构体，该方法中R-(-)-α-甲氧基-α-(三氟甲基)苯基乙酰衍生物的纯度>99%，定量下限为10μg/L。通过GC-MS在任何尿液样本中均未检测到d-甲基苯丙胺或d-苯丙胺。l-甲基苯丙胺的最大浓度中位数为62.8μg/L（范围：11.0 - 1440）。只有两名受试者检测到l-苯丙胺，其最大浓度与l-甲基苯丙胺的峰值水平一致，且始终≤母体最大浓度的4%。三种用于检测苯丙胺的商业免疫分析法EMIT(®) II Plus、KIMS(®) II和DRI(®)的灵敏度、特异性和效率分别为100%、97.8%、97.8%；100%、99.6%、99.6%和100%、100%、100%。这些免疫分析法具有较高的效率，但我们的第一个假设未得到证实。EMIT(®) II Plus分析法产生了2.2%的假阳性结果，需要进行对映体特异性确认。
