Cannabis Testing with Analytical HPLC

As the legalisation of cannabis for both medical and recreational use continues to advance, researchers are reliant on analytical HPLC to detect and characterise cannabinoids in various strains of the drug.

What are Cannabinoids?

The cannabis plant (Cannabis sativa) is a complex natural product that is known to produce at least 100 different compounds, many of which are present in extremely low concentrations. Many of the minor cannabinoids have shown some medicinal effects so it is important to have the ability to separate and identify them. Quantitative analysis of trace constituents such as cannabinoids (THC, CBN, CBD), pesticides and mycotoxins in cannabis flowers and concentrates requires sample cleanup prior to instrumental analysis and is essential in ensuring the safety, efficacy and quality of products.

Solutions for the purification and analysis of cannabis, hemp and cannabinoids

Liquid chromatography is central to cannabis testing applications. It has been used to help characterise the 100+ cannabinoids extracted from the cannabis plant.

Many market sectors use a combination of both preparative and analytical HPLC for quality assurance and control (QA/QC) protocols to ensure a safe product of highest quality. They include cannabinoid profiling, potency testing via quantification of THC (presence/absence of THC), determination of naturally occurring contaminants like mycotoxins and determination of artificial contaminants like pesticides.

High Performance Liquid Chromatography (HPLC) and Ultra Performance LC are ideal for potency determination as they can identify and measure structurally similar cannabinoids and their different forms (e.g. free form and corresponding acid forms of THC and CBD) in a single analysis.

Preparative chromatography is the method of choice when highly pure cannabinoids should be produced from cannabis plants or raw extracts.

Analytical HPLC provides a quantitative basis for classifying cannabis according to chemotype. It is superior to many alternative techniques as it is not temperature-dependent, which guarantees that even cannabinoids at the lowest concentration are unlikely to undergo decarboxylation. This ensures that analytical HPLC are more representative of the actual crop as it gives insight into cannabinoid concentration in the native state.

Potency determination with liquid chromatography products from Waters

Products: Alliance HPLC System and ACQUITY UPLC H-Class Plus works in combination with the CORTECS columns. An application note from Waters can be downloaded here.

Key benefits:

• Fit for purpose and robust HPLC solution for cannabinoid profiling
• 16 cannabinoids fully separated in just 26 minutes using HPLC
• Rapid analysis of cannabinoids under 10 minutes using UPLC method
• Separation of structurally similar cannabinoids using UPC2

Testing cannabis for pesticides

Testing cannabis for pesticides is very important to ensure product safety and quality. The number of regulated pesticides that are required to be monitored varies, as do the action limits which range from 0.01 µg/g (10 ppb) to above 1 µg/g (1 ppm). The QuEChERS method is proven to be very effective for multi-residue analysis of pesticides and mycotoxins in a wide variety of food and agricultural products including Cannabis samples.

Pesticides and Mycotoxins analysis using QuEChERS dispersive Solid Phase Extraction

Products for Mass Spectrometry (MS/MS): Xevo TQ-S micro and Xevo TQ-GC.

Key benefits:

• Simple extraction and dispersive SPE (dSPE) clean up procedure
• Simultaneous analysis of pesticides and mycotoxins
• Quantitative and confirmatory analysis using LC-MS/MS