11-Nor-9-carboxy-Δ9-tetrahydrocannabinol (Δ9-THCCOOH) is the most frequently detected illicit drug metabolite in the military drug testing program. An increasing number of specimens containing unresolved Δ8-THCCOOH prompted the addition of this analyte to the Department of Defense (DoD) drug testing panel. A method was developed and validated for the quantitative confirmation of the carboxylated metabolites of Δ8- and Δ9-THC in urine samples utilizing automated pipette tip dispersive solid phase extraction and analysis by liquid chromatography tandem mass spectrometry (LC-MS/MS). Analytes were separated isocratically over an 8.5 min runtime and detected on an MS/MS system equipped with an electrospray ionization source operating in negative mode. A single point calibrator (15 ng/mL) forced through zero demonstrated linearity from 3 to 1,000 ng/mL. Intra- and inter-day precision were ≤9.1% CV, and bias was within ±14.1% for Δ8-THCCOOH and Δ9-THCCOOH. No interferences were found after challenging the method with different over-the-counter drugs, prescription pharmaceuticals, drugs of abuse, and several cannabinoids and cannabinoid metabolites, including Δ1°-THCCOOH. Urine specimens presumptively positive by immunoassay (n=2939; 50 ng/mL Δ9-THCCOOH cutoff) were analyzed with this confirmation method. Specimens that contained Δ8-THCCOOH often had Δ9-THCCOOH above the 15 ng/mL cutoff. However, nearly one-third of the specimens analyzed were positive for Δ8-THCCOOH only. This manuscript describes the first validated automated extraction and confirmation method for Δ8- and Δ9-THCCOOH in urine that provides adequate analyte separation in urine specimens with extreme isomer abundance ratios.

中文翻译：

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11-Nor-9-羧基-四氢大麻酚异构体的自动提取和 LC-MS/MS 分析以及真实尿液样本中的患病率

11-Nor-9-羧基-Δ9-四氢大麻酚（Δ9-THCCOOH）是军事药物测试项目中最常检测到的非法药物代谢物。越来越多的样本含有未解析的 Δ8-THCCOOH，促使国防部 (DoD) 药物测试小组添加了这种分析物。开发并验证了一种方法，用于利用自动移液器吸头分散固相萃取和液相色谱串联质谱 (LC-MS/MS) 分析尿液样品中 Δ8- 和 Δ9-THC 的羧化代谢物的定量确认。在 8.5 分钟的运行时间内对分析物进行等度分离，并在配备以负离子模式运行的电喷雾电离源的 MS/MS 系统上进行检测。单点校准器 (15 ng/mL) 强制过零，表现出 3 至 1,000 ng/mL 的线性度。 Δ8-THCCOOH 和 Δ9-THCCOOH 的日内和日间精密度≤9.1% CV，偏差在±14.1% 以内。使用不同的非处方药、处方药、滥用药物以及几种大麻素和大麻素代谢物（包括 Δ1°-THCCOOH）对该方法进行挑战后，没有发现干扰。使用这种确认方法对免疫测定推定呈阳性的尿液样本（n=2939；50 ng/mL Δ9-THCCOOH 截止值）进行了分析。含有 Δ8-THCCOOH 的样品通常具有高于 15 ng/mL 截止值的 Δ9-THCCOOH。然而，近三分之一的分析样本仅对 Δ8-THCCOOH 呈阳性。该手稿描述了第一个经过验证的尿液中 Δ8- 和 Δ9-THCCOOH 的自动提取和确认方法，该方法可在具有极端异构体丰度比的尿液样本中提供充分的分析物分离。