States that have legalized cannabis typically require all cannabis products to undergo safety and quality testing. Most third party testing labs rely on a variety of technologies to determine cannabinoid potency, analyze terpene content, and detect the presence of common contaminants. But in the absence of federally standardized protocols, the preferred method for testing can vary from state to state.
Mass spectrometry and chromatography-based techniques are currently the most common, including:
- High Performance Liquid Chromatography (HPLC)
- LC-MS (liquid chromatography-mass spectrometry)
- LC-MS/MS (Liquid Chromatography tandem Mass Spectroscopy)
- Gas chromatography–mass spectrometry (GC-MS)
- Inductively coupled plasma mass spectrometry (ICP-MS)
But what if testing labs could condense their current catalog of analytical testing techniques? Here we’ll explore the potential of Nuclear Magnetic Resonance (NMR) to offer a more accurate, inexpensive, and broadly applicable testing method for the cannabis industry.
Simplifying Cannabis Testing with NMR
When compared to current methods, NMR has several key benefits. First and foremost, it offers a single method and instrument for carrying out multiple tests. Cannabinoid potency, terpene profiling, and heavy metal analysis, which currently require three separate testing methodologies, can all be performed using NMR.
By reducing the number of testing methods, labs can reduce the number of analytical instruments they need to purchase and maintain. Additionally, benchtop NMR instruments have become increasingly affordable. This saves both time and money, creating cost savings that can be passed down to customers.
Second, NMR is just as accurate as mass spectrometry and chromatography-based methods. In recent years, researchers have worked to enhance the NMR signal when analyzing complex materials like cannabis extracts. And one analysis found that benchtop NMR instruments provided comparable accuracy to HPLC for analyzing cannabinoid content in cannabis samples.
Another Way to Fingerprint Cannabis
Lastly, NMR also offers a streamlined method for the chemical profiling of cannabis strains, a technique referred to as cannabis fingerprinting. In an interview with Analytical Cannabis, Peter de B. Harrington, the director of the Center for Intelligent Chemical Instrumentation at Ohio University, described NMR as “an information rich method” that can identify the chemical makeup of a cannabis sample with less intensive data analysis.
“The idea is that by not quantifying the individual peaks, which is the metabolomic approach, but relying on the NMR spectrum as a fingerprint, much time and cost can be saved. Then, through pattern recognition, we can find key peaks that correspond to the pharmacological properties, the geographical location, strain, and hybrid, or quality.” explained Harrington.
Overall, NMR has the potential to offer a streamlined, cost-effective cannabis testing method with applications for evaluating the quality of cannabis products and chemically profiling individual strains to help consumers find a product that’s right for them.