Establishment of Detection Methods for Five Cannabinoids in Hemp Cosmetics Based on HPLC

A simultaneously HPLC detection method for cannabidiolic acid (CBDA), cannabidiol (CBD), cannabinol (CBN), Δ9- tetrahydrocannabinol (THC), tetrahydro-cannabinolic acid (THCA) in 3 kinds of cosmetics matrix containing hemp leaf extract was developed. The extraction and HPLC conditions were optimized, and a methodological verification was also carried out. The results showed that this method had a good linear relationship in the range of 0.25–50 μg/mL with LOD values for 5 cannabinoids all between 0.10–0.25 μg/g. The recovery rates of 5 cannabinoids in 3 different cosmetics matrixes were between 90.1–108.5%, and the RSD values were all below 4.4%. These results indicated that this method had the advantages of simple operation, high sensitivity, and good accuracy. Through the testing of 6 kinds of hemp cosmetics, it was found that such cosmetics had uneven quality. The establishment of this method can lay a methodological foundation for establishing relevant testing method standards.