Cámpora P, Bermejo A M, Tabernero M J, Fernández P
Institute of Legal Medicine, Forensic Toxicology Service, Faculty of Medicine, University of Santiago de Compostela, Spain.
J Anal Toxicol. 2003 Jul-Aug;27(5):270-4. doi: 10.1093/jat/27.5.270.
An analytical method for the simultaneous determination of cocaine (COC) and its major metabolites, ecgonine methyl ester (EME) and benzoylecgonine (BEG), in saliva was developed. The method involves liquid-liquid extraction in Toxitubes A, derivatization with 99:1 (v/v) N,O-bis-trimethylsilyltrifluoroacetamide (BSTFA)/trimethylchlorosilane (TMCS) and gas chromatography-mass spectrometry (GC-MS) determination. The detector response thus obtained is linear over the range 25-1000 ng/mL, with a reproducibility better than 93% and a recovery close to 100% for the three analytes. The limits of detection achieved were 0.9 ng/mL for EME, 2.2 ng/mL for cocaine, and 0.2 ng/mL for BEG, and the limits of quantitation were 3.0 ng/mL for EME, 7.4 ng/mL for cocaine, and 0.8 ng/mL for BEG. The proposed method was applied to 48 saliva samples from cocaine users, 96% of which were positive for the drug and/or its metabolites. Saliva is thus a suitable biological fluid for determining cocaine, EME, and BEG by GC-PCI-MS.
建立了一种同时测定唾液中可卡因（COC）及其主要代谢物芽子碱甲酯（EME）和苯甲酰芽子碱（BEG）的分析方法。该方法包括在Toxitubes A中进行液液萃取，用99:1（v/v）的N，O-双三甲基硅基三氟乙酰胺（BSTFA）/三甲基氯硅烷（TMCS）进行衍生化，以及气相色谱-质谱联用（GC-MS）测定。由此获得的检测器响应在25-1000 ng/mL范围内呈线性，三种分析物的重现性优于93%，回收率接近100%。EME的检测限为0.9 ng/mL，可卡因为2.2 ng/mL，BEG为0.2 ng/mL；EME的定量限为3.0 ng/mL，可卡因为7.4 ng/mL，BEG为0.8 ng/mL。所提出的方法应用于48份来自可卡因使用者的唾液样本，其中96%的样本对该药物和/或其代谢物呈阳性。因此，唾液是通过GC-PCI-MS测定可卡因、EME和BEG的合适生物流体。
