Evaluation and comparison of cannabidiol in hemps (Cannabis sativa L.) by high pressure liquid and gas chromatography

Master thesis of Arnas Julius Vasiliauskas. Evaluation and comparison of cannabidiol in hemps (Cannabis sativa L.) by high pressure liquid and gas chromatography/ scientific supervisor: prof. Liudas Ivanauskas; Lithuanian University of Health Sciences Faculty of Pharmacy, Department of Analytical and Toxicological Chemistry. – Kaunas. The aim of the study: to compare the results of hemp quantitative analysis, obtained by liquid chromatography and gas chromatography methods. The tasks of the study are to choose high pressure liquid chromatography method for qualitative and quantitative analysis of cannabidiol in hemps, to compare the results of cannabidiol quantitative analysis between different species and parts of hemp and to compare the the percentage composition of cannabidiol by high pressure liquid chromatography and gas chromatography. Methods - qualitative and quantitative evaluation of cannabidiol was made by high pressure liquid chromatography (HPLC) and gas chromatography (GC). Results - gradient elution was used to evaluate cannabidiol amount by HPLC: eluents: (B) acetonitrile and (A) formic acid (0,1%) : 0 min (B-75%), 6 min (B-100%.), 9 min B-100%., 10 min (B-75%.). For qualitative and quantitative GC analysis of cannabidiol helium was used as carrier gases, the temperature in column was risen from 80°C to 250° C 10°C/min and from 250°C to 310°C 30°C/min and was maintained for 7 min. Comparing different species of hemp, the highest concentration of cannabidiol was evaluated in Finola and Balobzevsky hemp species (respectively 6,64 and 6,31% or 6,42 and 6,1% using HPLC and GC). Comparing different parts of the plant, the highest concentration of cannabidiol was evaluated in pollen (6,64 and 6,3% determined in pollen of Finola species by HPLC and GC). The higher concentration of cannabidiol in all parts and species of hrmp was determined using high pressure liquid chromatography (2,15±0,02%), using gas chromatography - 2,01±0,01%. The average difference of gas chromatography analysis results was lower than 0,15% of total amount. Conclusions - When comparing the evaluation of cannabidiol by different methods, high pressure liquid chromatography takes more time, needs more reagents, but the concentration of cannabidiol was determined higher than by gas chromatography