Molecularly imprinted polymer for selective determination of Δ~9-tetrahydrocannabinol and 11-nor-Δ~9-tetrahydrocannabinol carboxylic acid using LC-MS/MS in urine and oral fluid

摘要

The use of molecularly imprinted polymers (MIPs) for solid phase extraction (MISPE) allows a rapid and selective extraction compared with traditional methods. Determination of Δ~9-tetrahydrocannabinol (THC) and 11- nor-Δ~9-tetrahydrocannabinol carboxylic acid (THC-COOH) in oral fluid (OF) and urine was performed using homemade MISPEs for sample clean-up and liquid chromatography tandem mass spectrometry (LC-MS/MS). Cylindrical MISPE shaped pills were synthesized using catechin as a mimic template. MISPEs were added to 0.5 mL OF or urine sample and sonicated 30 min for adsorption of analytes. For desorption, the MISPE was transfered to a clean tube, and sonicated for 15 min with 2 mL acetone:acetonitrile (3:1, v/v). The elution solvent was evaporated and reconstituted in mobile phase. Chromatographic separation was performed using a SunFire C18 (2.5 μm; 2.1×20 mm) column, and formic acid 0.1%and acetonitrile asmobile phase, with a total run time of 5 min. The method was fully validated including selectivity (no endogenous or exogenous interferences), linearity (1– 500 ng/mL in OF, and 2.5–500 ng/mL in urine), limit of detection (0.75 and 1 ng/mL in OF and urine, respectively), imprecision (%CV <12.3 %), accuracy (98.2–107.0 % of target), extraction recovery (15.9–53.5 %), process efficiency (10.1–46.2 %), and matrix effect (