Quantitation of Synthetic Cannabinoids Using LC-MS
Facing the ever-changing challenges of screening for synthetic cannabinoids is time-consuming. Learn how to streamline screening and increase your confirmational workflow sensitivity.
Overview: Synthetic cannabinoids were developed by pharmaceutical companies in an effort to mimic the beneficial effects of marijuana, such as pain relief and anti-nausea. After the synthetic compounds found their way into products like incense, they became illegal, and now they are tested in forensic toxicology labs for law enforcement purposes. While the parent compound of synthetic cannabinoids is not excreted in urine, other metabolites are, and thus they can be screened with liquid chromatography-mass spectrometry (LC-MS).
Method: A simple dilute and shoot quantitative method is used to analyze the alkyl-hydroxy and alkyl-carboxy metabolites of JWH-018 and 073: JWH-018-OH, JWH-018-COOH, JWH-073-OH and JWH-073-COOH in urine. Chromatographic analysis is performed using Thermo Scientific™ Accela™ 600 HPLC pump and a Thermo Scientific™ Hypersil™ GOLD column. MS analysis was carried out on a Thermo Scientific™ TSQ Quantum Ultra™ triple stage quadrupole mass spectrometer equipped with a heated electrospray ionization (HESI-II) probe.
Table 1. Inter-Assay %CV and % Bias for Quality Control Samples
Results: The method was linear from 2 to 1,000 ng/mL, with R2 values greater than 0.99 for all compounds, yielding an LOQ of 2 ng/mL for all compounds. Based on published research, using an SPE or liquid/liquid extraction processing method will lower the current LOQ to 0.2 ng/mL, if required.