Abstract: In this study, a method based on ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry (UPLC-MS-MS) was developed for the simultaneous determination of cannabinol, cannabidiol and Δ9-tetrahydrocannabinol in nine food matrices such as olive oil, beef and bread. The samples were extracted with acetonitrile or methanol and purified using an EMR or HLB solid-phase extraction (SPE) cartridge. The analytes were separated on a BEH C18 column (2.1 mm × 50 mm, 1.7 μm) using methanol and 10 mmol/L ammonium acetate in water as the mobile phase, ionized using an electrospray ionization (ESI) source in the positive ion mode, detected in the multiple reaction monitoring (MRM) mode, and quantified by the internal standard method. The calibration curves for all analytes showed good linearity in the concentration range of 0–200 μg/L, with correlation coefficients greater than 0.998. The limits of detection (at a signal to noise ratio of 3) and quantitation (at a signal to noise ratio of 10) were 3 and 10 μg/kg, respectively. The average recoveries for negative samples spiked at three concentration levels (1, 2, 10 times of the limit of quantitation) were 71.7%–108.5%, with relative standard deviations (RSDs) of 4.6%–12.4% (n = 6). In summary, this method has good stability and high sensitivity, and is suitable for simultaneous determination of the three cannabinoids in common food matrices.

Key words: cannabinoids; solid-phase extraction; isotope dilution; ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry