Krotulski Alex J, Mohr Amanda L A, Friscia Melissa, Logan Barry K
Center for Forensic Science Research and Education at the Fredric Rieders Family Foundation, 2300 Stratford Ave, Willow Grove, PA 19090, USA.
NMS Labs, 3701 Welsh Rd, Willow Grove, PA 19090, USA.
J Anal Toxicol. 2018 Apr 1;42(3):170-176. doi: 10.1093/jat/bkx105.
The collection and analysis of drugs in oral fluid (OF) at the roadside has become more feasible with the introduction of portable testing devices such as the Alere™ DDS®2 Mobile Test System (DDS®2). The objective of this study was to compare the on-site results for the DDS®2 to laboratory-based confirmatory assays with respect to detection of drugs of abuse in human subjects. As part of a larger Institutional Review Board approved study, two OF samples were collected from each participant at a music festival in Miami, FL, USA. One OF sample was field screened using the DDS®2, and a confirmatory OF sample was collected using the Quantisal™ OF collection device and submitted to the laboratory for testing. In total, 124 subjects participated in this study providing two contemporaneous OF samples. DDS®2 field screening yielded positive results for delta-9-tetrahydrocannabinol (THC) (n = 27), cocaine (n = 12), amphetamine (n = 3), methamphetamine (n = 3) and benzodiazepine (n = 1). No opiate-positive OF samples were detected. For cocaine, amphetamine, methamphetamine and benzodiazepines, the DDS®2 displayed sensitivity, specificity and accuracy of 100%. For THC, the DDS®2 displayed sensitivity of 90%, specificity of 100% and accuracy of 97.5%, when the threshold for confirmation matched that of the manufacturers advertised cut-off. When this confirmatory threshold was lowered to the analytical limit of detection (i.e., 1 ng/mL), apparent device performance for THC was poorer due to additional samples testing positive by confirmatory assay that had tested negative on the DDS®2, demonstrating a need for correlation between manufacturer cut-off and analytical reporting limit. These results from drug-using subjects demonstrate the value of field-based OF testing, and illustrate the significance of selecting an appropriate confirmation cut-off concentration with respect to performance evaluation and detection of drug use.
随着诸如Alere™ DDS®2移动检测系统（DDS®2）等便携式检测设备的引入，在路边采集和分析口腔液（OF）中的药物变得更加可行。本研究的目的是比较DDS®2的现场检测结果与基于实验室的确证检测方法在检测人体滥用药物方面的差异。作为一项经机构审查委员会批准的更大规模研究的一部分，在美国佛罗里达州迈阿密的一个音乐节上，从每位参与者处采集了两份口腔液样本。一份口腔液样本使用DDS®2进行现场筛查，另一份确证口腔液样本使用Quantisal™口腔液采集装置采集，并送往实验室进行检测。共有124名受试者参与了本研究，提供了两份同期的口腔液样本。DDS®2现场筛查对δ-9-四氢大麻酚（THC）（n = 27）、可卡因（n = 12）、苯丙胺（n = 3）、甲基苯丙胺（n = 3）和苯二氮䓬（n = 1）检测出阳性结果。未检测到阿片类阳性口腔液样本。对于可卡因、苯丙胺、甲基苯丙胺和苯二氮䓬，DDS®2的灵敏度、特异性和准确性均为100%。对于THC，当确证阈值与制造商公布的截断值相匹配时，DDS®2的灵敏度为90%，特异性为100%，准确性为97.5%。当该确证阈值降至检测限（即1 ng/mL）时，由于确证检测中额外的样本呈阳性，而这些样本在DDS®2检测中呈阴性，THC的设备表现明显变差，这表明需要在制造商截断值和分析报告限之间建立相关性。这些来自吸毒者的结果证明了现场口腔液检测的价值，并说明了在性能评估和药物使用检测方面选择合适的确证截断浓度的重要性。
