An Unusually High Cocaine Blood Concentration in an Impaired Driving Investigation

Cocaine is an illicit drug frequently encountered by forensic practitioners in driving under the influence of drugs (DUID) casework. Whole blood collected from a suspected drugged driver was found to contain 3.000 mg/L cocaine, 1.600 mg/L benzoylecgonine, and 0.260 mg/L methamphetamine. The high concentration of cocaine, while common in overdose death investigations, is unusual for an impaired driving case. Information from the officer revealed that the motorist swallowed cocaine during the traffic stop. Although a cocaine DUID charge could not be pursued, the blood methamphetamine concentration exceeded the State of Nevada “per se” limit for operating a motor vehicle. The motorist was successfully prosecuted for DUID based on his admission of using methamphetamine prior to driving and the blood methamphetamine result. This case highlights the importance of considering case history when interpreting laboratory results and the application of jurisdictional statutes as an approach to prosecuting suspected drug‐impaired drivers.     

LC-MS／MS测定尿液中可卡因及其代谢物苯甲酰爱康宁

目的建立尿液中可卡因(cocaine,COC)及其代谢物苯甲酰爱康宁(benzoylecgonine,BZE)的液相色谱-串联质谱分析方法。方法尿液经固相萃取后,用AllurePFP丙基柱分离,以V(甲醇):V(20mmol/L乙酸胺和0.1%甲酸的缓冲溶液)=80∶20为流动相,采用二级质谱多反应监测模式检测COC和BZE。按10mg/kg的剂量对豚鼠腹腔注射可卡因,给药后收集7d尿液。结果尿液中COC和BZE在2.0～100ng/mL质量浓度范围内线性关系良好(r=0.9995),最低检测限(LOD)为0.5ng/mL;回收率大于90%;日内和日间精密度均小于6%;豚鼠尿液中主要检测目标物是BZE,且BZE检测时限也较COC长。结论所建方法灵敏度高,选择性好,适用于尿液中可卡因和苯甲酰爱康宁的检测。     

Temporal analysis of the cocaine metabolite benzoylecgonine in wastewater to estimate community drug use*

Abstract: Indirect estimation methods of cocaine consumption may not reflect the real extent of cocaine use. Another approach is sewage epidemiology. This direct approach is based on analysis of a stable cocaine metabolite, benzoylecgonine (BE), in wastewater. Influent to the Lubbock (Texas) Water Reclamation Plant was sampled twice a week to assess weekly variations in estimates of cocaine consumption over a 5‐month period. BE was extracted from influent wastewater samples using solid phase extraction and analyzed using gas chromatography/mass spectrometry. Measured concentrations of BE were converted to cocaine equivalents; the estimated average daily consumption of cocaine during the study period was 1152 ± 147 g. Based on BE concentrations and sewage epidemiology, higher cocaine consumption was observed on weekends compared to weekdays (p < 0.0003). This method was effective in monitoring BE in wastewater and could be used to complement survey data in estimating cocaine use at a local level.     

可卡因及其代谢物苯甲酰爱康宁胶体金检测试剂盒的研制

目的根据胶体金免疫层析的原理,建立一种可以在现场快速检测可卡因及其代谢物苯甲酰爱康宁的方法。方法将胶体金标记的抗可卡因单克隆抗体均匀浸涂在玻璃纤维膜上,用点膜仪将可卡因的完全抗原以及羊抗鼠多抗在硝酸纤维素膜上划线,分别作为可卡因的检测区（T）和质控区（C）。并且对样品垫用0.2%Tween 20和0.5%PVA封闭处理。样本（尿样、唾液、血样等）中游离的可卡因及其代谢物同包被的完全抗原分别免疫竞争结合胶体金标记的抗可卡因单抗。肉眼观察试剂盒的质控区和检测区上有无紫红色带来判读结果。结果可卡因胶体金检测试剂盒对65种毒品、药物的特异性测试中仅识别可卡因及其代谢物。对人体尿样中的可卡因和苯甲酰爱康宁检测阈值均为300ng/mL。与GC/MS对照试验,其准确性分别为98.9%和98.6%。在常温下能稳定保存2年。结论该可卡因检测试剂盒在5min内可以检测出样本中的可卡因及其代谢物成分。     

A Direct Aqueous Derivatization GSMS Method for Determining Benzoylecgonine Concentrations in Human Urine

A sensitive and reliable method for extraction and quantification of benzoylecgonine (BZE) and cocaine (COC) in urine is presented. Propyl‐chloroformate was used as derivatizing agent, and it was directly added to the urine sample: the propyl derivative and COC were then recovered by liquid–liquid extraction procedure. Gas chromatography–mass spectrometry was used to detect the analytes in selected ion monitoring mode. The method proved to be precise for BZE and COC both in term of intraday and interday analysis, with a coefficient of variation (CV) <6%. Limits of detection (LOD) were 2.7 ng/mL for BZE and 1.4 ng/mL for COC. The calibration curve showed a linear relationship for BZE and COC (r² >0.999 and >0.997, respectively) within the range investigated. The method, applied to thirty authentic samples, showed to be very simple, fast, and reliable, so it can be easily applied in routine analysis for the quantification of BZE and COC in urine samples.