Method for the Analysis of Cannabinoids and Terpenes in Cannabis

Abstract

The requirements for an acceptable cannabis assay have changed dramatically over the years resulting in a large number of laboratories using a diverse array of analytical methodologies that have not been properly validated. Due to the lack of sufficiently validated methods, we conducted a single- laboratory validation study for the determination of cannabinoids and terpenes in a variety of commonly occurring cultivars. The procedure involves high- throughput homogenization to prepare sample extract, which is then profiled for cannabinoids and terpenes by HPLC-diode array detector and GC-flame ionization detector, respectively. Spike recovery studies for terpenes in the range of 0.03-1.5% were carried out with analytical standards, while recovery studies for Δ9-tetrahydrocannabinolic acid, cannabidiolic acid, Δ9-tetrahydrocannabivarinic acid, and cannabigerolic acid and their neutral counterparts in the range of 0.3-35% were carried out using cannabis extracts. In general, accuracy at all levels was within 5%, and RSDs were less than 3%. The interday and intraday repeatabilities of the procedure were evaluated with five different cultivars of varying chemotype, again resulting in acceptable RSDs. As an example of the application of this assay, it was used to illustrate the variability seen in cannabis coming from very advanced indoor cultivation operations.

Characterization of the Volatile Components of Cannabis Preparations by Solid-Phase Microextraction Coupled to Headspace-Gas Chromatography with Mass Detector (SPME-HSGC/MS)

“…Methyl oleate is the internal standard routinely used for the analysis of cannabinoids by GC/FID technique, but it has a too high boling point (218°C) for this kind of application. On the other hand, nonane that was indicated in the literature [10] as internal standard for the analysis of cannabinoids and terpenes in Cannabis, showed the suitable features to be used as internal standard.…”

“…Besides the biologically active cannabinoids, more than 90 phytocannabinoids have been isolated from Cannabis and its essential oil is a complex mixture containing also monoterpenoids and sesquiterpenoids [5][6][7][8], giving it the typical organoleptic properties. The volatiles constituents of Cannabis have been extensively studied [9] because they represent a potential for chemically fingerprinting different cultivars [10]. On the other hand, less attention was dedicated to the volatile components of hashish, despite the fact that they could be very useful for characterizing the different preparations and for establishing the origin and eventual links between different seizures [2].…”

Developing Robust Standardised Analytical Procedures for Cannabinoid Quantification: Laying the Foundations for an Emerging Cannabis-Based Pharmaceutical Industry

“…This may not only provide GC with a higher degree of chromatographic resolution than LC, but the derivatization process may also allow discrimination of isomeric cannabinoid species on the basis of silyl group number [56]. In contrast, LC does not require high temperatures for chromatographic separation, allowing for identification of native carboxylated cannabinoids within botanical forms [26, 57]. LC may also be more appropriate for quantitative cannabinoid determinations as compared with GC, as the derivatisation process cannot always be guaranteed to be exhaustive [56, 58, 59].…”

“…Despite the publication of more than 130 methods for the analysis of cannabinoids between 1990 and 2016 [51], few examples exist which have been validated using internationally recognised guidelines, such as those of the ICH [26]. Whilst a large number of analytical techniques have been employed for the quantification of Cannabis botanical raw material [28], including the monograph Cannabis Flos from the Dutch Office of Medicinal Cannabis, limited attention has been given to the quantification of cannabinoids within Cannabis botanical drug substances or CME [27-29, 52].…”

“…Despite the promising global outlook for Cannabis -based drug development, a critical step forward for this emerging industry is the establishment of robust standardised methods for the quantification of cannabinoids within a wide and growing range of Cannabis -based drug forms [26-29]. Refinement of these methodologies and standardisation of approach will be necessary to establish a foundation for future drug development, application and manufacture and will be required to ensure the identity, efficacy, purity, quality and potency of impending pharmaceutical-grade drugs derived from Cannabis .…”