Jagerdeo Eshwar, Schaff Jason E, Montgomery Madeline A, LeBeau Marc A
Federal Bureau of Investigation Laboratory, Quantico, VA 22135, USA.
Rapid Commun Mass Spectrom. 2009 Sep;23(17):2697-705. doi: 10.1002/rcm.4174.
Marijuana is one of the most commonly abused illicit substances in the USA, making cannabinoids important to detect in clinical and forensic toxicology laboratories. Historically, cannabinoids in biological fluids have been derivatized and analyzed by gas chromatography/mass spectrometry (GC/MS). There has been a gradual shift in many laboratories towards liquid chromatography/mass spectrometry (LC/MS) for this analysis due to its improved sensitivity and reduced sample preparation compared with GC/MS procedures. This paper reports a validated method for the analysis of Delta(9)-tetrahydrocannabinol (THC) and its two main metabolites, 11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THC-COOH) and 11-hydroxy-Delta(9)-tetrahydrocannabinol (THC-OH), in whole blood samples. The method has also been validated for cannabinol (CBD) and cannabidiol (CDN), two cannabinoids that were shown not to interfere with the method. This method has been successfully applied to samples both from living people and from deceased individuals obtained during autopsy. This method utilizes online solid-phase extraction (SPE) with LC/MS. Pretreatment of samples involves protein precipitation, sample concentration, ultracentrifugation, and reconstitution. The online SPE procedure was developed using Hysphere C8-EC sorbent. A chromatographic gradient with an Xterra MS C(18) column was used for the separation. Four multiple-reaction monitoring (MRM) transitions were monitored for each analyte and internal standard. Linearity generally fell between 2 and 200 ng/mL. The limits of detection (LODs) ranged from 0.5 to 3 ng/mL and the limits of quantitation (LOQs) ranged from 2 to 8 ng/mL. The bias and imprecision were determined using a simple analysis of variance (ANOVA: single factor). The results demonstrate bias as <7%, and imprecision as <9%, for all components at each quantity control level.
大麻是美国最常被滥用的非法物质之一，这使得大麻素在临床和法医毒理学实验室中的检测变得很重要。从历史上看，生物体液中的大麻素一直通过气相色谱/质谱联用仪（GC/MS）进行衍生化和分析。由于与GC/MS方法相比，液相色谱/质谱联用仪（LC/MS）具有更高的灵敏度和更少的样品制备步骤，许多实验室已逐渐转向使用LC/MS进行此项分析。本文报告了一种经过验证的方法，用于分析全血样本中的Δ⁹-四氢大麻酚（THC）及其两种主要代谢物，11-去甲-9-羧基-Δ⁹-四氢大麻酚（THC-COOH）和11-羟基-Δ⁹-四氢大麻酚（THC-OH）。该方法也已针对大麻酚（CBD）和大麻二酚（CDN）进行了验证，结果表明这两种大麻素不会干扰该方法。此方法已成功应用于来自活体和尸检期间获得的死者的样本。该方法采用在线固相萃取（SPE）与LC/MS联用。样品预处理包括蛋白质沉淀、样品浓缩、超速离心和复溶。在线SPE程序是使用Hysphere C8-EC吸附剂开发的。使用Xterra MS C₁₈柱进行色谱梯度分离。对每种分析物和内标监测四个多反应监测（MRM）转换。线性范围一般在2至200 ng/mL之间。检测限（LOD）范围为0.5至3 ng/mL，定量限（LOQ）范围为2至8 ng/mL。使用单因素方差分析（ANOVA）确定偏差和不精密度。结果表明，在每个质量控制水平下，所有成分的偏差均<7%，不精密度均<9%。
