ABSTRACT
An analytical method of ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC/PDA-QDa) for the qualitative and quantitative analysis of Δ9-tetrahydrocannabinol (Δ9-THC), cannabidiol (CBD), and cannabinol (CBN) in confiscated cannabis was developed.The seized cannabis was extracted in methanol by sonication.The binary mobile phase consisted of methanol (containing 0.1% formic acid) and water.After centrifugation, the supernatant was separated on Waters UPLC BEH C18 column (50 mm×2.1 mm, 1.7 μm) with isocratic elution at a flow rate of 0.2 mL/min.The three cannabinoids were analyzed by photodiode array (PDA) detector at 220 nm and confirmed by mass spectrometer QDa.The correlation coefficient of standard curve for the three cannabinoids in linearity range was not less than 0.999, as well as the recoveries were 82%-102% with the relative standard deviations (RSD) of 0.36%-4.12% at three spiked levels.The method is specific, easy, quick and suitable for confirmation of the cannabinoids in seized cannabis.Cannabis plants in different areas were classified by their chemical phenotype as drug-type or fiber-type plants, taking into account the phenotypic index Δ9-THC, (Δ9-THC+CBN)/CBD, or the Δ9-THC/CBD and the (Δ9-THC+CBN)/CBD ratios.The analysis of the original composition of plant material is necessary for the detection and the quality control of cannabis plants.