Integrated approach for the extraction and quality assessment of fibre-type Cannabis sativa L. based on UPLC-PDA and HPTLC

Recent research has emphasised the promising therapeutic potential of fibre-type Cannabis sativa L. (hemp) and related phytocannabinoids [1]. Among the most abundant and valuable non-psychoactive cannabinoids are cannabidiol (CBD) and cannabidiolic acid (CBDA), both exhibiting a wide spectrum of pharmacological activities [2]. Efficient analytical methodologies for cannabinoids determination are thus crucial for hemp quality testing and utilisation [3]. In this context, the present study aimed to develop an integrated procedure for the effective extraction and quantitative analysis of the major cannabinoids in hemp.

Ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and dynamic maceration (DM) were examined using EtOH as reference solvent [4]. UAE displayed superior performance and was further optimised through Design of Experiments (DoE), maximising the recovery of cannabinoids. Rapid and reliable quantification of principal cannabinoids was achieved by means of UPLC-PDA. The method was developed and validated utilising highly-pure cannabinoids isolated by centrifugal partition chromatography (CPC) [5]. Several extraction solvents were also evaluated using the optimised UAE protocol and UPLC-PDA. HPTLC densitometry combined with chemometrics was implemented for classification of the extracts obtained with different solvent types to ensure a broad range of bioactive compounds.

In this work, a highly-efficient UPLC-PDA method coupled with a simplified UAE-based extraction protocol is presented for the quantification of the principal cannabinoids in hemp. The proposed HPTLC methodology enables the rapid and cost-effective fingerprint analysis for solvent selection.

• References

• 1 Abrams DI. The therapeutic effects of Cannabis and cannabinoids: An update from the National Academies of Sciences, Engineering and Medicine report. Eur J Intern Med 2018; 49: 7-11.
• 2 Izzo AA, Borrelli F, Capasso R, Di Marzo V, Mechoulam R. Non-psychotropic plant cannabinoids: new therapeutic opportunities from an ancient herb. Trends Pharmacol Sci 2009; 30: 515-527
• 3 Citti C, Braghiroli D, Vandelli MA, Cannazza G. Pharmaceutical and biomedical analysis of cannabinoids: A critical review. J Pharm Biomed Anal 2018; 147: 565-579.
• 4 Brighenti V, Pellati F, Steinbach M, Maran D, Benvenuti S. Development of a new extraction technique and HPLC method for the analysis of non-psychoactive cannabinoids in fibre-type Cannabis sativa L. (hemp). J Pharm Biomed Anal 2017; 143: 228-236.
• 5 Popp JR, Petrakis EA, Angelis A, Halabalaki M, Bonn GK, Stuppner H, Skaltsounis LA. Rapid isolation of acidic cannabinoids from Cannabis sativa L. using pH-zone-refining centrifugal partition chromatography. J Chromatogr A. 2019 (in press).