Bar Adsorptive Microextraction for Trace Determination of Natural and Semi-Synthetic Cannabinoids in Saliva

Cannabis is the most widely consumed illicit substance worldwide, and the rise of synthetic and semi-synthetic cannabinoids poses growing public health concerns due to their high potency and unpredictable effects. This study presents a new analytical methodology for the simultaneous determination of natural and semi-synthetic cannabinoids (cannabidiol (CDB), Δ⁸-tetrahydrocannabinol (∆⁸-THC), Δ⁹-tetrahydrocannabinol (∆⁹-THC), and hexahydrocannabinol (HHC)) in saliva using gas chromatography coupled with mass spectrometry (GC-MS) in combination with bar adsorptive microextraction (BAμE) as a green sample preparation. The optimized method showed satisfactory recoveries (57.3–80.6%), low detection and quantification limits (1.25 and 4.13 ng/mL, respectively), excellent linearity (r² ≥ 0.9963), and robust precision and accuracy. Application to authentic saliva samples demonstrated cannabinoid levels consistent with literature values. Overall, the proposed methodology offers a cost-effective, miniaturized, and environmentally sustainable platform for routine oral fluid cannabinoid analysis, highlighting its potential for forensic, clinical, and toxicological applications.