Tag Archives: analytical

Sunrise Genetics Partners With RPC, Begins Genetic Testing in Canada

By Aaron G. Biros
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Sunrise Genetics, Inc., the parent company of Marigene and Hempgene, announced their partnership with New Brunswick Research & Productivity Council (RPC) this week, according to a press release. The company has been working in the United States for a few years now doing genomic sequencing and genetic research with headquarters based in Fort Collins, CO. This new partnership, compliant with Health Canada sample submission requirements, allows Canadian growers to submit plants for DNA extraction and genomic sequencing.

Sunrise Genetics researches different cannabis cultivars in the areas of target improvement of desired traits, accelerated breeding and expanding the knowledge base of cannabis genetics. One area they have been working on is genetic plant identification, which uses the plant’s DNA and modern genomics to create authentic, reproducible, commercial-ready strains.

Matt Gibbs, president of Sunrise Genetics, says he is very excited to get working on cannabis DNA testing in Canada. “RPC has a long track record of leadership in analytical services, especially as it relates to DNA and forensic work, giving Canadian growers their first real option to submit their plant samples for DNA extraction through proper legal channels,” says Gibbs. “The option to pursue genomic research on cannabis is now at Canadian cultivator’s fingertips.”

Canada’s massive new cannabis industry, which now has legal recreational and medical use, sales and cultivation, previously has not had many options for genetic testing. Using their genetic testing capabilities, they hope this partnership will better help Canadian cultivators easily apply genomic testing for improved plant development. “I’m looking forward to working with more Canadian cultivators and breeders; the opportunity to apply genomics to plant improvement is a win-win for customers seeking transparency about their Cannabis product and producers seeking customer retention through ‘best-in-class’ cannabis and protectable plant varieties,” says Gibbs. The partnership also ensures samples will follow the required submission process for analytical testing, but adding the service option of genetic testing so growers can find out more about their plants beyond the regular gamut of tests.

RPC is a New Brunswick provincial research organization (PRO), a research and technology organization (RTO) that offers R&D testing and technical services. With 130 scientists, engineers and technologists, RPC offers a wide variety of testing services, including air quality, analytical chemistry of cannabis, material testing and a large variety of pilot facilities for manufacturing research and development.

They have over 100 accreditations and certifications including an ISO 17025 scope from the Standards Council of Canada (SCC) and is ISO 9001:2008 certified. This genetic testing service for cannabis plants is the latest development in their repertoire of services. “This service builds on RPC’s established genetic strengths and complements the services we are currently offering the cannabis industry,” says Eric Cook, chief executive officer of RPC.

Ask The Expert: Exploring Cannabis Laboratory Accreditation Part 4

By Aaron G. Biros
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In the first part of this series, we spoke with Michelle Bradac, senior accreditation officer at A2LA, to learn the basics of cannabis laboratory accreditation. In the second part, we sat down with Roger Brauninger, A2LA Biosafety Program manager, to learn why states are looking to lab accreditation in their regulations for the cannabis industry. In the third part, we heard from Michael DeGregorio, chief executive officer of Konocti Analytics, Inc., discussing method development in the cannabis testing industry and his experience with getting accredited.

In the fourth and final part of this series, we sit down with Susan Audino, Ph.D., an A2LA lead assessor and instructor, laboratory consultant and board member for the Center for Research on Environmental Medicine in Maryland. Dr. Audino will share some insights into method validation and the most technical aspects of laboratory accreditation.

Susan Audino, Ph.D.

Susan Audino obtained her Ph.D. in Chemistry with an analytical chemistry major, physical and biochemistry minor areas. She currently owns and operates a consulting firm to service chemical and biological laboratories. Susan has been studying the chemistry and applications of cannabinoids and provides scientific and technical guidance to cannabis dispensaries, testing laboratories and medical personnel. Dr. Audino’s interest most directly involves cannabis consumer safety and protection, and promotes active research towards the development of official test methods specifically for the cannabis industry, and to advocate appropriate clinical research. In addition to serving on Expert Review Panels, she is also chairing the first Cannabis Advisory Panel and working group with AOAC International, is a member of the Executive Committee of the ASTM Cannabis Section and has consulted to numerous cannabis laboratories and state regulatory bodies.

CannabisIndustryJournal: What are the some of the most significant technical issues facing an accreditation body when assessing a cannabis-testing laboratory?

Susan: From the AB perspective, there needs to be a high level of expertise to evaluate the merits and scientific soundness of laboratory-developed analytical test methods. Because there are presently no standard or consensus test methods available, laboratories are required to develop their own methods, which need to be valid. Validating methods require a rigorous series of tests and statistical analyses to ensure the correctness and reliability of the laboratory’s product, which is– the test report.

CIJ: When is method validation required and how does this differ from system suitability?

Susan: Method validation is required whenever the laboratory modifies a currently accepted consensus or standard test method, or when the laboratory develops its own method. Method validation is characterized by a series of analytical performance criteria including determinations of accuracy, precision, linearity, specification, limit of detection, and limit of quantitation. The determination of system suitability requires a series of deliberate variations of parameters to ensure the complete system, that is all instrument(s) as well as the analytical method, is maintained throughout the entire analytical process. Traditionally, method validation has been referred to as “ruggedness” and system suitability as “robustness.”

CIJ: What are the most important aspects of method validation that must be taken into account? 

Susan: In keeping with the FDA guidelines and other accepted criteria, I tend to recommend the International Conference on Harmonization (ICH), particularly Q 2A, which is a widely recognized program that discusses the pertinent characteristics of method validation. This include: method specification, linearity, range, accuracy, and precision (e.g., repeatability, intermediate precision, reproducibility). As mentioned earlier, system suitability is also a critical element and although related to method validation, does require its own protocol.

CIJ: What three areas do you see the laboratory having the hardest time with in preparing for accreditation? 

Susan: My responses to this question assume the laboratory employs appropriate instruments to perform the necessary analyses, and that the laboratory employs personnel with experience and knowledge appropriate to develop test methods and interpret test results.

  • By and large, method validation that is not appropriate to the scope of their intended work. Driving this is an overall lack of information about method validation. Oftentimes there is an assumption that multiple recoveries of CRMs constitute “validation”. While it may be one element, this only demonstrates the instrument’s suitability. My recommendation is to utilize any one of a number of good single laboratory validation protocols. Options include, but are not limited to AOAC International, American Chemical Society, ASTM, and ICH protocols.
  • Second is the lack of statistically sound sampling protocols for those laboratories that are mandated by their governing states to go to the field to sample the product from required batches. Sampling protocols needs to address the heterogeneity of the plant, defining the batch, and determining/collecting a sample of sufficient quantity that will be both large enough and representative of the population, and to provide the laboratory an adequate amount from which to sub-sample.
  • Third, sample preparation. This is somewhat intertwined with my previous point. Once an appropriate sample has been collected, preparation must be relevant to the appropriate technology and assay. It is unlikely that a laboratory can perform a single preparation that is amenable to comprehensive testing.

Steep Hill Expands To Oregon

By Aaron G. Biros
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Last week, Steep Hill announced they are expanding into Oregon with a laboratory in Portland. According to the press release, the company has licensed its testing technology to Dr. Carl Balog, a renowned pain and addiction physician.

Steep Hill has expanded significantly over the past year, including new laboratories in Pennsylvania, Maryland, Washington D.C. and Hawaii, among other states. The Berkeley-based company works in lab testing, research and development, licensing, genetics and remote testing. In 2008, Steep Hill opened the first-ever commercial cannabis-testing laboratory in the country.

Jmîchaeĺe Keller, president and chief executive officer of Steep Hill, says this is a development that will help them better understand cannabis chemistry and its medical applications. “We are pleased to announce our expansion into Oregon and especially pleased to partner with Dr. Balog, a physician who brings years of pain and addiction experience to the Steep Hill body of expertise,” says Keller. “In addition, Dr. Balog plans to use his specialized knowledge to aid Steep Hill’s research and development efforts to broaden our understanding of cannabis chemistry and to explore its wider medical applications. In partnering with Dr. Balog, we hope that Steep Hill will be able to help physicians around the United States to curb the opioid epidemic by offering Steep Hill Verified™ medicinal cannabis as an alternative to a crisis that plagues this country.”

Examination of cannabis prior to testing- credit Steep Hill Labs, Inc.

Dr. Balog, now owner and medical director of Steep Hill Oregon, says medical cannabis could be an excellent harm reduction tool, and hints at it being a possible tool in the opioid crisis. “I deal with the consequences of the opioid epidemic on a daily basis as a pain and addiction specialist,” says Dr. Balog. “The growing trend of using cannabis products as an alternative to opioids highlights the need for regulated testing. Because of the variability of marijuana preparations, testing ensures that scientific rigor is applied in a standardized way. I am dedicated to ensuring that patients have access to safe, tested cannabis, free from contaminants and to verified labels that can be trusted for their content.”

They expect Steep Hill Oregon to be open for business in the second quarter of 2018.

Ask The Expert: Exploring Cannabis Laboratory Accreditation Part 3

By Aaron G. Biros
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In the first part of this series, we spoke with Michelle Bradac, senior accreditation officer at A2LA, to learn the basics of cannabis laboratory accreditation. In the second part, we sat down with Roger Brauninger, A2LA Biosafety Program manager, to learn why states are looking to lab accreditation in their regulations for the cannabis industry.

In the third part of this series, we sit down with Michael DeGregorio, chief executive officer of Konocti Analytics, Inc., to talk method development in the cannabis testing industry and his experience with getting accredited. In the final part of this series, we are going to sit down with Susan Audino, an instructor at A2LA to learn more about the requirements where she’ll offer some advice for labs seeking accreditation.

Michael DeGregorio, chief executive officer of Konocti Analytics, Inc.

Michael DeGregorio is a doctor of pharmacy with an extensive career in medicine and scientific research. He’s worked in cancer research and medicine, teaching at the University of California, San Francisco, Yale University School of Medicine, University of Texas, Health Science Center at San Antonio and University of California, Davis. Before becoming the CEO of Konocti Analytics, a laboratory based in California, DeGregorio was also a published author in a large number of peer-reviewed medical journals.

In this piece, we sit down with DeGregorio to find out what challenges labs face when getting accredited, why they sought accreditation and their experience with getting off the ground. Stay tuned for the final part of this series!

CannabisIndustryJournal: How does a laboratory go about choosing an appropriate method in an industry where, generally, there are no validated methods available?

Michael DeGregorio: Our approach to developing analytical methods for testing cannabis began with a review of the existing laboratories and their methods, where we found no standardization and inconsistent results. Since cannabis is being used by the public and as a medicine, our goal is to help make it as contaminant-free as possible for the well-being of the consumer, and this begins by developing a state-of-the-art analytical facility.

When developing new methods, we review the published literature to see what has already been done and try to arrive at a scientifically sound consensus. We then perform experiments to determine which set of conditions works best for us. Once we have developed an appropriate method, we validate it pursuant to ISO/IEC 17025 requirements.

CIJ: How do you go about choosing what type of equipment to use for testing (e.g. by limit of detection, acceptable method use of equipment for other industries, etc.)?

Michael: After reviewing the operations of other testing laboratories, we concluded that, in general, they were not taking advantage of the most advanced technologies and had limited personnel qualified to operate it. Because public safety is our main concern, we chose state-of-the-art equipment, including GC/LC-MS with Orbitrap and ICP-MS, for testing medicinal cannabis. In addition to identifying unknown pesticides, we needed the capability of performing full chemical screening of all samples for potentially harmful compounds, e.g. steroids, present in cannabis, as well as the ability to detect trace levels of metals.

Our greatest concern is the fact that pesticides in cannabis have not been adequately studied. Current pesticide regulations suggest that government authorities believe that there are a finite number of pesticides available. Smart farmers could easily avoid the pesticides on current lists. Because of this, we chose to validate our pesticide methods with a focus on chemical classes, as opposed to specific pesticides, to give us the broadest possible coverage of potential compounds. The Orbitrap mass spectrometers also allow us to detect and identify unknown pesticides. This is something not currently being done by other laboratories. The latest microbiology methods for cannabis testing include DNA analysis, and for this we use qRT-PCR technology. Finally, the high sensitivity of ICP-MS allows for the detection of metals concentrations that may be harmful, yet undetectable by other means.

CIJ: What do you feel are the benefits of being accredited?

Michael: Being accredited shows the public that we have made a commitment to quality analytics. We feel this gives our clients peace of mind when marketing their products, knowing that they have been tested by a laboratory meeting the highest international standards of operation available using the latest technology. Furthermore, being accredited requires participation in ongoing proficiency testing programs, which helps maintain analytical competency. It should be pointed out that any prospective client of an analytical facility should take into account the laboratory’s full accredited scope of testing to ensure its competency.

CIJ: What challenges did you face during the process of getting your laboratory started and/or during the accreditation process?

Michael: Developing the quality management system and getting our equipment and processes to a state where they met accreditation requirements took several months of hard work, and turned out to be a bit more daunting than we anticipated. Our pre-accreditation assessment revealed that much work remained to be done, and it gave us a real appreciation for the level of detail and documentation required. We remained determined and eventually achieved our accreditation.

CIJ: What are the benefits to the grower and dispensaries to choosing an accredited laboratory for the testing of their product?

Michael: By choosing an accredited laboratory with a full scope of testing (potency, pesticides, mycotoxins, metals, microbiology, residual solvents and terpenes), growers and dispensaries can rest assured that their products have been tested using validated methods with appropriate quality control by trained, competent personnel. For growers, this makes their products more attractive to potential buyers. For dispensaries, this means they can confidently market their products with the knowledge that the information shown on the label is accurate, which in turn gives their customers peace of mind that the product they are consuming does not contain unacceptable levels of contaminants. 

CIJ: Why did you choose A2LA?

Michael: Once we decided to pursue accreditation, we researched the various accrediting bodies available as well as their reputations. We discovered that while all accrediting bodies are themselves accredited to the same standard, accreditation by the various bodies was not considered equal in practice. In our opinion, A2LA was considered the most prestigious, highly regarded accrediting body. Furthermore, some of the most prestigious laboratories in the country are accredited by A2LA, including Los Alamos National Laboratory, the Food and Drug Administration’s Center for Biologics Evaluation and Research, Lawrence Livermore National Laboratory, Centers for Disease Control, Federal Bureau of Investigation and the United States Department of Agriculture. Many of our preferred sources of scientific supplies and services are accredited by A2LA as well. As our goal was to be accredited by the best available accrediting body, we chose A2LA.

EVIO Labs Expands To Florida

By Aaron G. Biros
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Currently, there are no lab testing regulations for Florida’s medical cannabis market. Chris Martinez, co-founder and chief operating officer of EVIO Labs Florida, a veteran-owned business, is looking to change that.

Chris Martinez, co-founder and chief operating officer of EVIO Labs Florida

When Martinez co-founded EVIO Labs Florida, he saw the need for a dedicated cannabis lab to ensure safety and quality of medicine for patients in the state. Partnering with EVIO Labs to accomplish this goal, Martinez secured a 5,500 sq. ft. facility in Broward County to test for potency, pesticides, microbial contaminants, terpenes, residual solvents and heavy metals. Their lab, a first of its kind in the industry, qualifies as a true pharmaceutical-grade clean room. This week, Martinez also secured their 2nd laboratory location in the City of Gainsville, where they will test for potency, microbials, terpenes and residual solvents. And he isn’t doing it on the cheap. “Our Broward lab is powered by Shimadzu with over $1.2M in the latest testing equipment utilizing LCMS technology with the world’s fastest polarity switching time of 5 m/sec and scan speeds of 30,000 u/sec with UF Qarray sensitivity 90 times that of previously available technologies,” says Martinez.

Martinez, an entrepreneur at heart, started the lab with a team of experts to become the first completely cannabis-focused laboratory in Florida. Jorge Segredo, their head chemist and quality assurance director, has over 18 years of experience in the development of nutraceutical and pharmaceutical products under ISO and FDA accreditation. Segredo has helped launch three independent FDA-accredited laboratories and has extensive knowledge of HPLC, GCMS, LCMS, ICPMS technologies and development/validation of testing methods and procedures. Cynthia Brewer, their director of operations, was an active participant in the 2017 state legislative session and has been an advocate for medical cannabis, working with legislators on a suitable framework to increase patient access to cannabis.

The EVIO team is using instruments from Shimadzu

EVIO is one of the nation’s leaders in cannabis testing, research science and advisory services. It is an evolving network of laboratories with nine EVIO cannabis laboratories operating in five different states: Oregon, Colorado, Massachusetts, Florida and California. “After speaking with industry chemists around the country for months, the EVIO name was constantly brought up in conversation,” says Martinez. “When we spoke with the EVIO Team it was an easy decision for us to partner.” He says Lori Glauser, chief operating officer of EVIO, and William Waldrop, chief executive officer of EVIO, are truly visionaries in the cannabis industry.

According to Martinez, their licensing agreement with EVIO Labs (OTC:SGBYD) marked a first for the publicly traded company with exclusivity in the Florida market. The agreement includes proprietary testing methodologies, operating procedures, training and support.

In addition to testing cannabis for safety and quality, they are launching a technology platform called MJ Buddy, essentially a software tool that takes efficacy feedback from patients and uses testing and genetic data they gather from EVIO Labs across the country. “This will provide real data to the cannabis industry as to the medical benefits for thousands of patients in relation to the genotype and cannabinoid profiles of their medicine,” says Martinez.

Of the states that have legalized some form of cannabis, a large number of them have some lab testing regulations on the book, with some more comprehensive than others. Martinez says he hopes the Florida Department of Health, Office of Medical Marijuana Use follows some of the more thorough state programs, such as Oregon. His team has compiled a set of documents for regulators with recommendations for regulating the lab testing industry.

Without any regulations on paper, it is up to businesses to produce safe and quality medicine, without any oversight. EVIO Labs Florida follows FDA Good Laboratory Practices, has an ISO 17025:2005 accreditation pending, and is working on TNI 2016 accreditation.

When discussing what he wants to see happen with Florida’s regulatory framework, Martinez says the rules need to be specific to Florida. For example, due to the climate being so humid, microbial contaminant testing for things like yeast and mold will be particularly imperative. Because processing methods like butane and alcohol extraction are legal, he emphasizes the need for comprehensive residual solvents testing. “The most important regulation would be to have the laboratories select the samples at the MMTC facility and have the state randomly verify laboratory results to ensure accurate unbiased testing,” says Martinez.

In addition to that, he hopes their pesticide thresholds will be realistic and based on actual science. “We believe the public should receive carcinogenic data for products that are inhaled,” says Martinez. “Chemicals may be introduced into the processing of cannabis to vape liquid that may cause harm. This is important information for public health and communication of the risk related to exposure to such materials.” Martinez says EVIO Labs Florida was founded on the belief that through technology and science we can increase safety and patient outcomes.

Ask the Expert: Q&A with Steve Stadlmann on Cannabis lab Accreditation

By Aaron G. Biros
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Steve Stadlmann has an extensive background as an analytical chemist working in laboratories since the early 90’s. He is now a sales specialist at PerkinElmer, an analytical instrument manufacturer that provides instruments for cannabis testing labs, in addition to a host of other industries. With over two decades of experience working in environmental testing labs, food and beverage labs and agricultural testing labs, Stadlmann is extremely familiar with the instruments used in cannabis labs.

Steve Stadlmann, sales specialist at Perkin Elmer

In 2014, he started working in the cannabis space with TriQ, Inc., a technology solutions provider for cannabis growers, where he worked in product development on a line of nutrients. In April of 2016, he started working at Juniper Analytics, a cannabis-testing laboratory in Bend, Oregon. As laboratory director there, he created their quality manual, quality assurance plan, SOP’s and all the technical documentation for ORELAP accreditation. He developed new methodologies for cannabis testing industry for residual solvents, terpene profiles and potency analysis. He worked with PerkinElmer on pesticide methodology for the QSight™ Triple Quadrupole LC/MS/MS system and implemented operational procedures and methods for LC-UV, GCMS and LC-MS/MS, including sample prep for cannabis products.

He left Juniper Analytics about two months ago to work with PerkinElmer as a sales specialist. With extensive experience in helping get Juniper’s lab accredited, he is a wealth of knowledge on all things cannabis laboratory accreditation. PerkinElmer will be hosting a free webinar on September 12th that takes a deep dive into all things cannabis lab accreditation. Ahead of the upcoming webinar, Getting Accreditation in the Cannabis Industry, we sit down with Stadlmann to hear his observations on what instruments he recommends for accreditation, and processes and procedures to support that. Take a look at our conversation below to get a glimpse into what this webinar will discuss.

CannabisIndustryJournal: How can cannabis labs prepare for accreditation with selecting instrumentation?

Steve: Finding the appropriate instrumentation for the regulations is crucial. Ensuring the instrumentation not only has the capabilities of analyzing all the required compounds, but also able to achieve appropriate detection limit requirements. In addition, having an instrument manufacturer as a partner, that is willing and able to assist in method development, implementation and continued changes to the testing requirements at the state level (and potentially national level) is key.

Another consideration is robustness of the equipment. The instrumentation must be capable of high throughput for fast turnaround times of results. Unlike the environmental industry, the cannabis industry has consumer products with expiration dates. Clients demand quick turnaround of results to get product to market as quickly as possible and avoid sitting on inventory for any length of time.

To add to the robustness need, sample matrices in the cannabis industry can be quite challenging in relation to analytical instrumentation. Equipment that is able to handle these matrices with minimal downtime for routine service is becoming a requirement to maintain throughput needs of the industry.

CIJ: What are the most crucial procedures and practices for achieving ISO 17025 accreditation?

Steve: Development and documentation of processes and procedures following Good Laboratory Practices and procedures is essential to a successful accreditation process. Great attention must be paid to the quality objectives of the laboratory as well as associated documentation, including tracking of any errors, deviations, updates, complaints, etc.

Data integrity is a key component to any accrediting body and includes implementation and/or development of appropriate methods with support data proving acceptable results. In addition, documentation of all procedures and processes along with tracking of all steps in the process during routine laboratory work should be a priority. The ability to show a complete, documented trail of all procedures done to any sample is important in ensuring the results can be reproduced and ensuring no deviations occurred, in turn potentially causing questionable results.

Last but not least: training. Laboratory staff should be well versed in any procedures they are involved in to ensure high data quality and integrity. If any laboratory staff does not receive appropriate training in any operating procedures, the data quality becomes suspect.

CIJ: What are some of the biggest obstacles or pitfalls cannabis labs face when trying to get accredited?

Steve: Not fully preparing to meet any agency and testing regulations and requirements will cause delays in the accreditation process and potentially more work for the laboratory. From documentation to daily operations, if any aspect becomes a major finding for an auditor, additional data is usually required to prove the error has been fixed satisfactorily.

Taking the time early on to ensure all documentation, processes and procedures are adhering to any regulatory agency requirements is important for a smooth accreditation process. It is easy to overlook small details when building out the operating procedures that might be essential in the process. Again, going back to data quality, the laboratory must ensure all steps are outlined and documented to ensure high quality (reproducible) data and integrity.

A new employee should be able to come in and read a quality manual and standard operating procedure and produce equivalent data to any laboratory analyst doing the same job. With difficult or challenging operating procedures it becomes even more important that training and documentation are adhered to.


PerkinElmer’s free webinar will dive into these points and others in more detail. To learn more and sign up, click here.

The Practical Chemist

Potency Analysis of Cannabis and Derivative Products: Part 2

By Rebecca Stevens
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As mentioned in Part 1, the physiological effects of cannabis are mediated by a group of structurally related organic compounds known as cannabinoids. The cannabinoids are biosynthetically produced by a growing cannabis plant and Figure 1 details the biosynthetic pathways leading to some of the most important cannabinoids in plant material.

Potency figure 1
Figure 1: The biosynthetic pathway of phytocannabinoid production in cannabis has been deeply studied through isotopic labeling experiments

The analytical measurement of cannabinoids is important to ensure the safety and quality of cannabis as well as its extracts and edible formulations. Total cannabinoid levels can vary significantly between different cultivars and batches, from about 5% up to 20% or more by dry weight. Information on cannabinoid profiles can be used to tailor cultivars for specific effects and allows end users to select an appropriate dose.

Routine Analysis vs. Cannabinomics 

Several structurally analogous groups of cannabinoids exist. In total, structures have been assigned for more than 70 unique phytocannabinoids as of 2005 and the burgeoning field of cannabinomics seeks to comprehensively measure these compounds.¹

Considering practical potency analysis, the vast majority of cannabinoid content is accounted for by 10-12 compounds. These include Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabigerol (CBG), Δ9-tetrahydrocannabivarian (THCV), cannabidivarin (CBDV) and their respective carboxylic acid forms. The cannabinoids occur primarily as carboxylic acids in plant material. Decarboxylation occurs when heat is applied through smoking, vaporization or cooking thereby producing neutral cannabinoids which are more physiologically active.

Potency Analysis by HPLC and GC

Currently, HPLC and GC are the two most commonly used techniques for potency analysis. In the case of GC, the heat used to vaporize the injected sample causes decarboxylation of the native cannabinoid acids. Derivatization of the acids may help reduce decarboxylation but overall this adds another layer of complexity to the analysis² ³. HPLC is the method of choice for direct analysis of cannabinoid profiles and this technique will be discussed further.

A sample preparation method consisting of grinding/homogenization and alcohol extraction is commonly used for cannabis flower and extracts. It has been shown to provide good recovery and precision² ³. An aliquot of the resulting extract can then be diluted with an HPLC compatible solvent such as 25% water / 75% acetonitrile with 0.1% formic acid. The cannabinoids are not particularly water soluble and can precipitate if the aqueous percentage is too high.

To avoid peak distortion and shifting retention times the diluent and initial mobile phase composition should be reasonably well matched. Another approach is to make a smaller injection (1-2 µL) of a more dissimilar solvent. The addition of formic acid or ammonium formate buffer acidifies the mobile phase and keeps the cannabinoid acids protonated.

The protonated acids are neutral and thus well retained on a C18 type column, even at higher (~50% or greater) concentrations of organic solvent² ³.

Detection is most often done using UV absorbance. Two main types of UV detectors are available for HPLC, single wavelength and diode array. A diode array detector (DAD) measures absorbance across a range of wavelengths producing a spectrum at each point in a chromatogram while single wavelength detectors only monitor absorbance at a single user selected wavelength. The DAD is more expensive, but very useful for detecting coelutions and interferences.

References

  1. Chemical Constituents of Marijuana: The Complex Mixture of Natural Cannabinoids. Life Sciences, 78, (2005), pp. 539
  2. Development and Validation of a Reliable and Robust Method for the Analysis of Cannabinoids and Terpenes in Cannabis. Journal of AOAC International, 98, (2015), pp. 1503
  3. Innovative Development and Validation of an HPLC/DAD Method for the Qualitative and Quantitative Determination of Major Cannabinoids in Cannabis Plant Material. Journal of Chromatography B, 877, (2009), pp. 4115

Rebecca is an Applications Scientist at Restek Corporation and is eager to field any questions or comments on cannabis analysis, she can be reached by e-mail, rebecca.stevens@restek.com or by phone at 814-353-1300 (ext. 2154)