Development and validation of a GC-MS method for quantification of terpenes in cannabis oil (Cannabis sativa L.). Application to commercially available preparations in Argentina

Terpenes are aromatic compounds present in cannabis oil and are responsible for the characteristic aroma of cannabis. Terpenes and cannabinoids share biosynthetic pathways, and synergic and/or entourage actions of terpenes and cannabinoids have been reported. For this reason, the determination and quantification of terpenes are fundamental for the evaluation of cannabis oil preparations for medicinal purposes. We have developed, optimized, and validated a procedure for the detection and quantification of α-pinene, β-pinene, β-myrcene, limonene, linalool, and β-caryophyllene in cannabis oil using gas chromatography coupled to mass spectrometry. For optimization, two parameters were evaluated, namely extraction solvent, and extraction time. Linearity was obtained for all target analytes in the concentration range of 2.4–4800.0 ng/mL, presenting determination coefficients above 0.99. The lower limits of quantification were 2.4 ng/mL for all compounds. The intra- and intermediate precision, calculated in terms of coefficient of variation, were 1.7–10.1 and 3.5–9.6%, respectively. The method recoveries ranged from 99.7% to 107.8%. Verification of method validity was performed with authentic cannabis oil samples. To our knowledge, the herein described analytical method is the first available in Argentina, validated according to international guidelines, for quantification of α-pinene, β-pinene, β-myrcene, limonene, linalool, and β-caryophyllene in cannabis oil. In addition, the validated methodology is simple, sensitive, and suitable for the application in laboratories for the routine analysis of terpenes in cannabis oil samples.