Tag Archives: accurate

Innovations in Dosing Technologies: Getting an Accurate Hit, Every Time

By Michael Sassano
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Cannabis products and medicines are progressing rapidly, eating away at the market share of smokable flower. Currently, the general adult use cannabis market is split in three, in order of popularity: cannabis flower, vaporizers and ingestible products like edibles or capsules. In the medical market, flower is increasingly being replaced by alternative methods of delivery – and the same trend is now starting to be seen in the adult use market.

This is to be expected to some extent. Initially, only flower was available to medical cannabis users. On top of not everyone feeling comfortable with smoking, inhaling a combustible substance into the lungs is not the healthiest consumption method for those already suffering from a serious illness.

In the present day, there are new alternatives to smoking that come without the risk and actually have additional benefits. For example, there are now much more precise ways to measure your cannabinoid intake than weighing out the flower you’re about to burn. As technology develops, there is an expectation that – despite flower sales being fairly stable last year – we will see continued incremental growth in the non-flower category, especially on the medical side.

Oral Cannabinoid Delivery

Thankfully for those who want to use non-smokable products, there are a growing number of alternative oral products that are currently available in the market or are under development.

Some of the many infused products on the market today.

Cannabis edibles might be the first products to come to mind when you think about non-smokable products – but for many medicinal users, these are actually a fairly unpopular option. While having a cannabis-infused brownie or gummy might be quite discreet compared to smoking a joint, the need for patients to take in extra sugar or extra calories every time they need to take their medicine can be off-putting. Additionally, tradionally infused edibles can take between one to three hours to feel as the body needs time to digest.

Cannabinoid capsules or pills have recently emerged as an equally discreet alternative to edibles. These pills come in many forms, including hard capsules containing ground cannabis flower, softgel capsules containing measured doses of cannabis extract, and gelatin-free alternatives. Though these pills, like edibles themselves, do come with a relatively long onset time.

Cannabinoid capsules

Pills and edibles are also both affected by first-pass metabolism. This means that the active cannabinoids will be processed through the digestive system and the liver before passing onto the brain or the other organs. During this process, some amount of CBD or THC will likely be broken down by the body before it can make its effect felt, leading to inaccuracies between the labelled dose of a product and the active dose that reaches the brain or target area in the body.

To avoid these problems with first-pass metabolism, some have turned to use sublingual cannabis oils and tinctures. By placing a measured dose of oil under the tongue using a dropper, this theoretically allows for the fast absorption of THC or CBD into the bloodstream without the product being processed by the digestive system. However, in practice, these sublingual tinctures need to be held under the tongue for around ten minutes before they are fully absorbed. This is fairly difficult to do without accidentally swallowing some amount of the tincture, and so this still introduces some amount of uncertainty with dosing.

Fast-Acting Absorption

Fast-acting absorption techniques and nano emulsions are also gaining in popularity. Nanotechnologies and techniques have been developed by many firms, and boast claims of increasing absorption through the digestive system in order to effectively double the volume of cannabinoids absorbed into the body. Nano emulsions are also promising, which come with claims of up to four to five times more improved absorption. Such technologies rely on cannabis oils being immiscible with water-based substances, and process these cannabis oils in such a way that they become nanoscale droplets suspended in a larger mixture. Because of their size, these small pockets of cannabis oil are able to be absorbed rapidly through the gastrointestinal tract and into the bloodstream.

A drink additive, made by Splash Nano, that uses nano emulsion technology

Older liposomal and newer nano-liposomal combinations have also boasted similar claims. Liposomes are commonly used as a novel drug delivery system for pharmaceutical products to facilitate the absorption of drugs into the body, and the adaption of such techniques for the cannabis sector is also intended to dramatically improve the absorption of cannabinoids into the bloodstream. Given the marketing of these products, it can become confusing to know which is the best. The only way to know for sure is to have either a breath or blood analysis to see which style works and is best for the individual consumer.

As manufacturers progress from flower and basic products, the largest brands and more advanced medical companies are all producing ingestible products with fast absorption methods and additives. The difference is pronounced and significant enough that consumers and patients are starting to demand fast absorption products. As the market becomes more educated, you can expect that the market for fast absorption ingestible products will greatly outpace the older, more basic formulations. Of course, some emulsion additives will increase the operating costs for businesses, but over time, this difference will likely be fairly minimal.

Microencapsulation to boost cannabinoid absorption

Microencapsulation is another new method for producing drugs with high bioavailabilities, and the technique has recently made headlines in the cannabis industry.

Using a technique known as ionic gelation, or ionotropic gelation, scientists are able to trap drugs inside nano- or microscale capsules. These tiny capsules are robust enough to be able to protect the active drug ingredient–which in this case would be CBD or another cannabinoid–against the harsh environment of the gastrointestinal tract without necessarily limiting bioavailability.

The structure of cannabidiol (CBD), one of 400 active compounds found in cannabis.

Unlike the other oral dosing methods, cannabinoid microcapsules are not yet a commercially available product. However, there is early research indicating that this drug delivery technology could be a significant step forward in terms of improving cannabinoid bioavailability and absorption.

Published in the journal PLOS One, a new study from a team of Australian scientists reports that CBD microcapsules used in combination with a permeation-modifying bile acid can boost the peak concentration of CBD reaching the brain by 300 percent. These peak concentrations of CBD in the body also happened much earlier with the CBD microcapsules than with regular CBD oil, reflecting a faster absorption by the body.

This improved absorption and bioavailability addresses many of the limitations seen with traditional oral cannabinoid delivery. However, there is still potentially a very long road before these microcapsules are approved for general use in humans, making them an unrealistic option at present.

Metered Dose Inhalers

So far as innovative cannabis dosing technology that is currently available on the market goes, metered dose inhalers lead the way. Making up one-third of the market share, these devices are easy to use, discreet and are far less invasive than burning cannabis flower.

A metered dose inhaler by MÜV

Heating and vaporizing a purified cannabinoid also exposes the user to fewer potentially harmful combustion products than smoking flower. Using vapes, manufacturers are also able to adjust the formulation of vape oils in order to deliver a truly consistent product. This can help the consumer to truly measure their intake of beneficial cannabinoids.

Vaporizers for general adult use are very common now and come in many forms and flavors. Until recently though, there were very few vaporizers that met the specific needs of the medical market, like being able to deliver very controlled doses of cannabinoids. Now, innovation in the sector has led to a number of companies developing special metered dose inhalers for this purpose. These devices use smart technology to only heat and vaporize a pre-set controlled dose of cannabis oil from their compatible cartridges, allowing for intake to be tracked more precisely. This is different from regular vapes, where the amount inhaled can vary depending on how deeply a person inhales, or other environmental factors.

Recently, Syqe Medical received approval from Health Canada for their metered dose cannabis vaporizer. There is already a similar registration for approval in the US and Europe that looks promising for similar devices.

Recreational acceptance of products, like these high-tech vaporizers, drives up spending on innovations that would otherwise just be novel ideas. The cannabis industry has a wealth of creative talent, and with the market beginning to tear away from flower and towards novel and innovative products, like vaporizers and fast acting ingestible products, now is the time for the medical market to invest in this talent and follow the demand and the money.

ISO/IEC 17025 Accreditation Falls Short for Cannabis Testing Laboratories

By Kathleen May
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What is the role of the Quality Control (QC) Laboratory?

The Quality Control (QC) laboratory serves as one of the most critical functions in consumer product manufacturing. The QC laboratory has the final say on product release based on adherence to established product specifications. Specifications establish a set of criteria to which a product should conform to be considered acceptable for its intended use. Specifications are proposed, justified and approved as part of an overall strategy to ensure the quality, safety, and consistency of consumer products. Subsequently, the quality of consumer products is determined by design, development, Good Manufacturing Practice (GMP) controls, product and process validations, and the specifications applied throughout product development and manufacturing. These specifications are specifically the validated test methods and procedures and the established acceptance criteria for product release and throughout shelf life/stability studies.

The Code of Federal Regulations, 21 CFR Part 211, Good Manufacturing Practice for Finished Pharmaceuticals, provides the minimum requirements for the manufacture of safe products that are consumed by humans or animals. More specifically, 21 CFR Part 211: Subpart I-Laboratory Controls, outlines the requirements and expectations for the quality control laboratory and drug product testing. Additionally, 21 CFR Part 117, Current Good Manufacturing Practice, Hazard Analysis, and Risk-Based Preventative Controls for Human Food: Subpart B-Processes and Controls states that appropriate QC operations must be implemented to ensure food products are safe for consumption and food packing materials and components are safe and fit for purpose. Both food and drug products must be tested against established specifications to verify quality and safety, and laboratory operations must have the appropriate processes and procedures to support and defend testing results.

ISO/IEC 17025, General Requirements for the Competence of Testing and Calibration Laboratories is used to develop and implement laboratory management systems. Originally known as ISO/IEC Guide 25, first released in 1978, ISO/IEC 17025 was created with the belief that “third party certification systems [for laboratories] should, to the extent possible, be based on internationally agreed standards and procedures”7. National accreditation bodies are responsible for accrediting laboratories to ISO/IEC 17025. Accreditation bodies are responsible for assessing the quality system and technical aspects of a laboratory’s Quality Management System (QMS) to determine compliance to the requirements of ISO/IEC 17025. ISO/IEC 17025 accreditation is pursued by many laboratories as a way to set them apart from competitors. In some cannabis markets accreditation to the standard is mandatory.

The approach to ISO/IEC 17025 accreditation is typically summarizing the standard requirements through the use of a checklist. Documentation is requested and reviewed to determine if what is provided satisfies the item listed on the checklist, which correlate directly to the requirements of the standard. ISO/IEC 17025 covers the requirements for both testing and calibration laboratories. Due to the wide range of testing laboratories, the standard cannot and should not be overly specific on how a laboratory would meet defined requirements. The objective of any laboratory seeking accreditation is to demonstrate they have an established QMS. Equally as critical, for product testing laboratories in particular, is the objective to establish GxP, “good practices”, to ensure test methods and laboratory operations verify product safety and quality. ISO/IEC 17025 provides the baseline, but compliance to Good Laboratory Practice (GLP), Good Manufacturing Practice (GMP) and even Good Safety Practices (GSP) are essential for cannabis testing laboratories to be successful and demonstrate testing data is reliable and accurate.

Where ISO/IEC 17025 accreditation falls short

Adherence to ISO/IEC 17025, and subsequently receiving accreditation, is an excellent way to ensure laboratories have put forth the effort to establish a QMS. However, for product testing laboratories specifically there are a number of “gaps” within the standard and the accreditation process. Below are my “Top Five” that I believe have the greatest impact on a cannabis testing laboratory’s ability to maintain compliance and consistency, verify data integrity and robust testing methods, and ensure the safety of laboratory personnel.

Standard Operating Procedures (SOPs)

The understanding of what qualifies as a Standard Operating Procedure (SOP) is often misunderstood by cannabis operators. An SOP is a stand-alone set of step-by-step instructions which allow workers to consistently carry out routine operations, and documented training on SOPs confirms an employee’s comprehension of their job tasks. Although not required per the current version of the standard, many laboratories develop a Quality Manual (QM). A QM defines an organization’s Quality Policy, Quality Objectives, QMS, and the procedures which support the QMS. It is not an uncommon practice for cannabis laboratories to use the QM as the repository for their “procedures”. The intent of a QM is to be a high-level operations policy document. The QM is NOT a step-by-step procedure, or at least it shouldn’t be.

Test Method Transfer (TMT)

Some cannabis laboratories develop their own test methods, but a common practice in many cannabis laboratories is to purchase equipment from vendors that provide “validated” test methods. Laboratories purchase equipment, install equipment with pre-loaded methods and jump in to testing products. There is no formal verification (what is known as a Test Method Transfer (TMT)) by the laboratory to demonstrate the method validated by the vendor on the vendor’s equipment, with the vendor’s technicians, using the vendor’s standards and reagents, performs the same and generates “valid” results when the method is run on their own equipment, with their own technician(s), and using their own standards and reagents. When discrepancies or variances in results are identified (most likely the result of an inadequate TMT), changes to test methods may be made with no justification or data to support the change, and the subsequent method becomes the “validated” method used for final release testing. The standard requires the laboratory to utilize “validated” methods. Most laboratories can easily provide documentation to meet that requirement. However, there is no verification that the process of either validating in house methods or transferring methods from a vendor were developed using any standard guidance on test method validation to confirm the methods are accurate, precise, robust and repeatable. Subsequently, there is no requirement to define, document, and justify changes to test methods. These requirements are mentioned in ISO/IEC 17025, Step 7.2.2, Validation of Methods, but they are written as “Notes” and not as actual necessities for accreditation acceptance.

Change Control

The standard speaks to identifying “changes” in documents and authorizing changes made to software but the standard, and subsequently the accreditation criteria, is loose on the requirement of a Change Control process and procedure as part of the QMS. The laboratory is not offered any clear instruction of how to manage change control, including specific requirements for making changes to procedures and/or test methods, documented justification of those changes, and the identification of individuals authorized to approve those changes.

Out of Specification (OOS) results

The documentation and management of Out of Specification (OOS) testing results is perhaps one of the most critical liabilities witnessed for cannabis testing laboratories. The standard requires a procedure for “Nonconforming Work”. There is no mention of requiring a root cause investigation, no requirement to document actions, and most importantly there is no requirement to document a retesting plan, including justification for retesting. “Testing into compliance”, as this practice is commonly referred to, was ruled unacceptable by the FDA in the highly publicized 1993 court case United States vs. Barr Laboratories.

Laboratory Safety

FDAlogoSafe laboratory practices are not addressed at all in ISO/IEC 17025. A “Culture of Safety” (as defined by the Occupational Safety and Health Administration (OSHA)) is lacking in most cannabis laboratories. Policies and procedures should be established to define required Personal Protective Equipment (PPE), the safe handling of hazardous materials and spills, and a posted evacuation plan in the event of an emergency. Gas chromatography (GC) is a common test method utilized in an analytical testing laboratory. GC instrumentation requires the use of compressed gas which is commonly supplied in gas cylinders. Proper handling, operation and storage of gas cylinders must be defined. A Preventative Maintenance (PM) schedule should be established for eye wash stations, safety showers and fire extinguishers. Finally, Safety Data Sheets (SDSs) should be printed and maintained as reference for laboratory personnel.

ISO/IEC 17025 accreditation provides an added level of trust, respect and confidence in the eyes of regulators and consumers. However, the current process of accreditation misses the mark on the establishment of GxP, “good practices” into laboratory operations. Based on my experience, there has been some leniency given to cannabis testing laboratories seeking accreditation as they are “new” to standards implementation. In my opinion, this is doing cannabis testing laboratories a disservice and setting them up for failure on future accreditations and potential regulatory inspections. It is essential to provide cannabis testing laboratory owners and operators the proper guidance from the beginning and hold them up to the same rigor and scrutiny as other consumer product testing laboratories. Setting the precedence up front drives uniformity, compliance and standardization into an industry that desperately needs it.

References:

  1. 21 Code of Federal Regulations (CFR) Part 211- Good Manufacturing Practice for Finished Pharmaceuticals.
  2. 21 Code of Federal Regulations (CFR) Part 117;Current Good Manufacturing Practice, Hazard Analysis, and Risk-Based Preventative Controls for Human Food: Subpart B-Processes and Controls.
  3. ICH Q7 Good Manufacturing Practice Guidance for Active Pharmaceutical Ingredients; Laboratory Controls.
  4. World Health Organization (WHO).
  5. International Building Code (IBC).
  6. International Fire Code (IFC).
  7. National Fire Protection Association (NFPA).
  8. Occupational Safety and Health Administration; Laboratories.
  9. ASTM D8244-21; Standard Guide for Analytical Operations Supporting the Cannabis/Hemp Industry.
  10. org; ISO/IEC 17025.
Dr. Ed Askew
From The Lab

Quality Plans for Lab Services: Managing Risks as a Grower, Processor or Dispensary, Part 4

By Dr. Edward F. Askew
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Dr. Ed Askew

In the last three articles, I discussed the laboratory’s responses or defenses used to reply to your questions about laboratory results that place stress on the success of your business. The Quality Control (QC) results can cause this stress if they are not run correctly to answer the following questions:

  1. Are the laboratory results really true?
  2. Can the laboratory accurately analyze sample products like my sample?
  3. Can the laboratory reproduce the sample results for my type of sample?

Now let’s discuss the most important QC test that will protect your crop and business. That QC sample is the Matrix Sample. In the last article in this series, you were introduced to many QC samples. The Matrix Sample and Duplicate were some of them. Take a look back at Part 3 to familiarize yourself with the definitions.

The key factors of these QC sample types are:

  1. Your sample is used to determine if the analysis used by the laboratory can extract the analyte that is being reported back to you. This is performed by the following steps:
    1. Your sample is analyzed by the laboratory as received.
    2. Then a sub-sample of your sample is spiked with a known concentration of the analyte you are looking for (e.g. pesticides, bacteria, organic chemicals, etc.).
    3. The difference between the sample with and without a spike indicates whether the laboratory can even find the analyte of concern and whether the percent recovery is acceptable.
    4. Examples of failures are from my experiences:
      1. Laboratory 1 spiked a known amount of a pesticide into a wastewater matrix. (e.g. Silver into final treatment process water). The laboratory failed to recover any of the spiked silver. Therefore the laboratory results for these types of sample were not reporting any silver, but silver may be present. This is where laboratory results would be false negatives and the laboratory method may not work on the matrix (your sample) correctly. .
      2. Laboratory 2 ran an analysis for a toxic compound (e.g. Cyanide in final waste treatment discharge). A known amount of cyanide was spiked into a matrix sample and 4 times the actual concentration of that cyanide spike was recovered. This is where laboratory results would be called false positives and the laboratory method may not work on the matrix (your sample) correctly.
  2. Can the laboratory reproduce the results they reported to you?
    1. The laboratory needs to repeat the matrix spike analysis to provide duplicate results. Then a comparison of the results from the first matrix spike with its duplicate results will show if the laboratory can duplicate their test on your sample.
      1. If the original matrix spike result and the duplicate show good agreement (e.g. 20% relative percent difference or lower). Then you can be relatively sure that the result you obtained from the laboratory is true.
      2. But, if the original matrix spike result and the duplicate do not show good agreement (e.g. greater than 20% relative percent difference). Then you can be sure that the result you obtained from the laboratory is not true and you should question the laboratory’s competence.

Now, the question is why a laboratory would not perform these matrix spike and duplicate QC samples? Well, the following may apply:

  1. These matrix samples take too much time.
  2. These matrix samples add a cost that the laboratory cannot recover.
  3. These matrix samples are too difficult for the laboratory staff to perform.
  4. Most importantly: Matrix samples show the laboratory cannot perform the analyses correctly on the matrix.

So, what types of cannabis matrices are out there? Some examples include bud, leaf, oils, extracts and edibles. Those are some of the matrices and each one has their own testing requirements. So, what should you require from your laboratory?

  1. The laboratory must use your sample for both a matrix spike and a duplicate QC sample.
  2. The percent recovery of both the matrix spike and the duplicate will be between 80% and 120%. If either of the QC samples fail, then you should be notified immediately and the samples reanalyzed.
  3. If the relative percent difference between the matrix spike and the duplicate will be 20% or less. If the QC samples fail, then you should be notified immediately and the samples should be reanalyzed.

The impact of questionable laboratory results on your business with failing or absent matrix spike and the duplicate QC samples can be prevented. It is paramount that you hold the laboratory responsible to produce results that are representative of your sample matrix and that are true.

The next article will focus on how your business will develop a quality plan for your laboratory service provider with a specific focus on the California Code Of Regulations, Title 16, Division 42. Bureau Of Cannabis Control requirements.

extractiongraphic

The Four Pillars of Cannabis Processing

By Christian Sweeney
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extractiongraphic

Cannabis extraction has been used as a broad term for what can best be described as cannabis processing. A well-thought-out cannabis process goes far beyond just extraction, largely overlapping with cultivation on the front-end and product development on the back-end1. With this in mind, four pillars emerge as crucial capabilities for developing a cannabis process: Cultivation, Extraction, Analytics and Biochemistry.

The purpose and value of each pillar on their own is clear, but it is only when combined that each pillar can be optimized to provide their full capacities in a well-designed process. As such, it is best to define the goals of each pillar alone, and then explain how they synergize with each other.

At the intersection of each pillar, specific technology platforms exist that can effectively drive an innovation and discovery cycle towards the development of ideal products.Cultivation is the foundation of any horticultural process, including cannabis production. Whether the goal be to convert pigments, flavors or bioactive compounds into a usable form, a natural process should only utilize what is provided by the raw material, in this case cannabis flower. That means cultivation offers a molecular feedstock for our process, and depending on our end goals there are many requirements we may consider. These requirements start as simply as mass yield. Various metrics that can be used here include mass yield per square foot or per light. Taken further, this yield may be expressed based not only on mass, but the cannabinoid content of the plants grown. This could give rise to a metric like CBD or THC yield per square foot and may be more representative of a successful grow. Furthermore, as scientists work to learn more about how individual cannabinoids and their combinations interact with the human body, cultivators will prioritize identifying cultivars that provide unique ratios of cannabinoids and other bioactive compounds consistently. Research into the synergistic effect of terpenes with cannabinoids suggests that terpene content should be another goal of cultivation2. Finally, and most importantly, it is crucial that cultivation provide clean and safe materials downstream. This means cannabis flower free of pesticides, microbial growth, heavy metals and other contaminants.

Extraction is best described as the conversion of target molecules in cannabis raw material to a usable form. Which molecules those are depends on the goals of your product. This ranges from an extract containing only a pure, isolated cannabinoid like CBD, to an extract containing more than 100 cannabinoids and terpenes in a predictable ratio. There are countless approaches to take in terms of equipment and process optimization in this space so it is paramount to identify which is the best fit for the end-product1. While each extraction process has unique pros and cons, the tunability of supercritical carbon dioxide provides a flexibility in extraction capabilities unlike any other method. This allows the operator to use a single extractor to create extracts that meet the needs of various product applications.

Analytics provide a feedback loop at every stage of cannabis production. Analytics may include gas chromatography methods for terpene content3 or liquid chromatography methods for cannabinoids 3, 4, 5. Analytical methods should be specific, precise and accurate. In an ideal world, they can identify the compounds and their concentrations in a cannabis product. Analytics are a pillar of their own due simply to the efforts required to ensure the quality and reliability of results provided as well as ongoing optimization of methods to provide more sensitive and useful results. That said, analytics are only truly harnessed when paired with the other three pillars.

extractiongraphic
Figure 1: When harnessed together the pillars of cannabis processing provide platforms of research and investigation that drive the development of world class products.

Biochemistry can be split into two primary focuses. Plant biochemistry focuses back towards cultivation and enables a cannabis scientist to understand the complicated pathways that give rise to unique ratios of bioactive molecules in the plant. Human biochemistry centers on how those bioactive molecules interact with the human endocannabinoid system, as well as how different routes of administration may affect the pharmacokinetic delivery of those active molecules.

Each of the pillars require technical expertise and resources to build, but once established they can be a source of constant innovation. Fig. 1 above shows how each of these pillars are connected. At the intersection of each pillar, specific technology platforms exist that can effectively drive an innovation and discovery cycle towards the development of ideal products.

For example, at the intersection of analytics and cultivation I can develop raw material specifications. This sorely needed quality measure could ensure consistencies in things like cannabinoid content and terpene profiles, more critically they can ensure that the raw material to be processed is free of contamination. Additionally, analytics can provide feedback as I adjust variables in my extraction process resulting in optimized methods. Without analytics I am forced to use very rudimentary methods, such as mass yield, to monitor my process. Mass alone tells me how much crude oil is extracted, but says nothing about the purity or efficiency of my extraction process. By applying plant biochemistry to my cultivation through the use of analytics I could start hunting for specific phenotypes within cultivars that provide elevated levels of specific cannabinoids like CBC or THCV. Taken further, technologies like tissue culturing could rapidly iterate this hunting process6. Certainly, one of the most compelling aspects of cannabinoid therapeutics is the ability to harness the unique polypharmacology of various cannabis cultivars where multiple bioactive compounds are acting on multiple targets7. To eschew the more traditional “silver bullet” pharmaceutical approach a firm understanding of both human and plant biochemistry tied directly to well characterized and consistently processed extracts is required. When all of these pillars are joined effectively we can fully characterize our unique cannabis raw material with targeted cannabinoid and terpene ratios, optimize an extraction process to ensure no loss of desirable bioactive compounds, compare our extracted product back to its source and ensure we are delivering a safe, consistent, “nature identical” extract to use in products with predictable efficacies.

Using these tools, we can confidently set about the task of processing safe, reliable and well characterized cannabis extracts for the development of world class products.

[1] Sweeney, C. “Goal-Oriented Extraction Processes.” Cannabis Science and Technology, vol 1, 2018, pp 54-57.

[2] Russo, E. B. “Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects.” British Journal of Pharmacology, vol. 163, no. 7, 2011, pp. 1344–1364.

[3] Giese, Matthew W., et al. “Method for the Analysis of Cannabinoids and Terpenes in Cannabis.” Journal of AOAC International, vol. 98, no. 6, 2015, pp. 1503–1522.

[4] Gul W., et al. “Determination of 11 Cannabinoids in Biomass and Extracts of Different Varieties of Cannabis Using high-Performance Liquid Chromatography.” Journal of AOAC International, vol. 98, 2015, pp. 1523-1528.

[5] Mudge, E. M., et al. “Leaner and Greener Analysis of Cannabinoids.” Analytical and Bioanalytical Chemistry, vol. 409, 2017, pp. 3153-3163.

[6] Biros, A. G., Jones, H. “Applications for Tissue Culture in Cannabis Growing: Part 1.” Cannabis Industry Journal, 13 Apr. 2017, www.cannabisindustryjournal.com/feature_article/applications-for-tissue-culture-in-cannabis-growing-part-1/.

[7] Brodie, James S., et al. “Polypharmacology Shakes Hands with Complex Aetiopathology.” Trends in Pharmacological Sciences, vol. 36, no. 12, 2015, pp. 802–821.