Development of Gas-Chromatographic Method for Simultaneous Determination of Cannabinoids and Terpenes in Hemp.

Jure Zekič,Mitja Križman

doi:10.3390/molecules25245872

Abstract

An original gas chromatographic method has been developed for simultaneous determination of major terpenes and cannabinoids in plant samples and their extracts. The main issues to be addressed were the large differences in polarity and volatility between both groups of analytes, but also the need for an exhaustive decarboxylation of cannabinoid acidic forms. Sample preparation was minimised, also by avoiding any analyte derivatisation. Acetone was found to be the most appropriate extraction solvent. Successful chromatographic separation was achieved by using a medium polarity column. Limits of detection ranged from 120 to 260 ng/mL for terpenes and from 660 to 860 ng/mL for cannabinoids. Parallel testing proved the results for cannabinoids are comparable to those obtained from established HPLC methods. Despite very large differences in concentrations between both analyte groups, a linear range between 1 and 100 µg/mL for terpenes and between 10 and 1500 µg/mL for cannabinoids was determined.

Highlights

The hemp plant (Cannabis sativa and Cannabis indica), or cannabis, is a plant that has excited much interest throughout history because of its characteristics and various possibilities of use
The use of cannabinoids in a wide variety of preparations is growing, which is reflected in increased cannabis production
As already pointed out by Namdar et al [7], optimum solvent composition for terpenes and cannabinoids differs. They found the mixture of ethanol:hexane (3:7, v/v) to be the best compromise for extracting both groups of compounds

Summary

Introduction

The hemp plant (Cannabis sativa and Cannabis indica), or cannabis, is a plant that has excited much interest throughout history because of its characteristics and various possibilities of use. Hemp is known to contain various groups of compounds, probably the most characteristic among them are cannabinoids. Cannabis contains diverse terpenes, flavonoids, and some other groups of compounds [6,7,8,9]. Cannabinoids are probably the most studied metabolites of cannabis. Many of their beneficial effects on human health are already known, and there is a lot of ongoing research, discovering new ones [10]. The use of cannabinoids in a wide variety of preparations is growing, which is reflected in increased cannabis production. A number of methods for the analysis of cannabinoids in cannabis have already been developed; among various approaches, the predominant is chromatographic analysis, in particular using gas chromatography (GC) [11,12,13,14,15,16,17,18] or high performance liquid chromatography (HPLC) [16,19,20,21,22,23,24,25,26,27]

Methods

Results

Conclusion