Bringing Trusted Techniques and Technology to the Cannabis Testing Lab
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Translating knowledge and technology from fields like food and pharma to the cannabis testing sector is an important process and one that is helping to provide medical patients and recreational consumers with safe thoroughly tested cannabis. Many of the equipment, instrumentation and consumables providers who have been active in other regulated testing industries for years are assisting in these efforts. They have a wealth of knowledge that can help overcome some of the unique challenges faced in the cannabis testing lab and support proficient cannabis testing. One such company, Restek, have been supporting the industry for around 8 years and are passionate about enabling their customers to carry out their vital work.
To find out more about the technologies, support and research innovations Restek bring to the cannabis market, we spoke to Ashlee Reese who’s recently been focusing her efforts on this rapidly growing field. Ashlee has worked at Restek for the past 7 years in multiple roles including time as a quality control technician and research and development chemist.
JR: Restek has been involved in the cannabis industry for a number of years. How has the field developed and how are you supporting your customers as the industry grows?
AR: In my opinion, the cannabis industry has changed rapidly since 2010, which was when Restek first started to focus on the analytical testing sector of the market. And, continues to evolve and grow at speed. I’ve noticed that one of the fastest growing needs of the market is legitimacy. Stakeholders in testing laboratories, producers, processors, and dispensaries want the cannabis market to be rightly treated as a serious and legitimate industry. This is why you’ll hear most people in laboratories use proper terminology for the plant, place a strong emphasis on method standardization, and focus on acquiring accreditation. Restek has been providing this market with applications and consumables since 2010 for both product safety and product quality. So far, this includes supporting testing for potency, pesticides, residual solvents, mycotoxins, and terpenes.
JR: You’ve published some exciting results on the use of LC-UV for cannabinoid profiling. Why did you choose to explore the potential of this technique and what did you find?
AR: Most states with some form of cannabis legalization have implemented cannabinoid testing requirements for consumer safety purposes. It’s common for reporting requirements to include both neutral and acidic cannabinoids (cannabinoids containing a carboxylic group) to be analyzed for potency. While GC is a great technique for residual solvents and terpene analysis, the introduction of acidic cannabinoids in a 250°C inlet leads to their thermal degradation unless samples are derivatized prior to analysis. If left underivatized, the acidic cannabinoids which undergo decarboxylation will result in a falsely elevated concentration to the counterpart neutral cannabinoid i.e. THCA will degrade to THC. HPLC avoids this degradation issue. Thus, HPLC is the best laboratory practice for analyzing cannabinoids. When developing our latest cannabinoid method, we took into consideration several pain points that customers potentially face within the industry. These include the need for high sample throughput, capital investment for a system (LC-UV vs LC-MS), and possible terpene and other cannabinoid interferences. During method development, it was found that common LC methods actually result in a co-elution of CBNA and THC which can result in a positive bias for reported THC concentrations. With pain points and critical pairs in mind, Justin Steimling developed an isocratic method that resolves 16 cannabinoids in 9 minutes. Interestingly, it was found that ocimenes, a terpene that readily absorbs UV light at 228 nm, did not impact the quantitation of the 16 cannabinoids monitored. Finally, it was concluded that the method could be utilized on a traditional HPLC-UV system, but could also be translated to UHPLC-UV by pairing an appropriate UHPLC system with Restek’s UHPLC Raptor particles for faster runtimes while maintaining the integrity of the original separation.
JR: Restek has also been working on methods for analyzing residual solvents in cannabis concentrates. What challenges are typically faced with this kind of analysis?
AR: Colton Myers, another Restek applications chemist has been doing great work regarding residual solvents for the industry. There are several techniques that can be used for analyzing residual solvents in cannabis products. Colton is developing a high throughput method for residual solvents by utilizing a sample preparation salting procedure and headspace syringe technique. Colton has been posting what he has learned regarding this work on Restek’s ChromaBLOGraphy. There’s a lack of standardization of methods for residual solvents. Each state has their own set of testing requirements and analyte reporting lists. While some states might only require reporting 6 residual solvents on a certificate of analysis (CoA), other states require more than 15 to be reported. The federal prohibition of transferring cannabis across states lines makes proficiency testing nationwide virtually impossible. This greatly complicates the accuracy of cannabis testing for residual solvents. These challenges also exist for other cannabis analyses including potency, terpenes, mycotoxins, pesticides, etc.
JR: How have you found the cannabis industry so far and, what’s next for Restek in this emergent market?
AR: The cannabis industry is fascinating, exciting, and a great opportunity from both a commercial prospect and a scientific perspective as well. Learning as much as we can about every compound within the plant poses a significant analytical challenge. Since historical and widely accepted methods have not been completely established in the cannabis industry yet, scientists have a rare opportunity to create codified methods. Beyond the scientific aspects of study, the industry provides unique opportunities for entrepreneurship, economic growth, and a tremendous opportunity for many different communities to interact and form lasting relationships. Above all, I’m pleased to see the acceptance of the legitimacy of the cannabis industry grow as the market matures.
I see Restek continuing to support and provide the cannabis industry with fast, accurate, and reliable analytical testing solutions. We demonstrate this in blogs, application notes, and presentations on our website, conferences, and direct customer visits. Moving forward, Restek is expanding its outreach through other channels as well. For example, we’re developing a cannabis webinar regarding basic chromatography principles and a workflow solutions video pertaining to the LC-UV potency publication mentioned earlier in this article. Creating easily accessible modes of information and expertise for customers is part of Restek’s mission to provide a plus-1 experience.
Ashlee Reese, Associate Business Development Manager for the Cannabis market for Restek, was speaking to Jack Rudd, Managing Editor for Analytical Cannabis.