Quality control (QC) and standardized testing are essential to meet the increasing demand for safe, high-quality medicinal and recreational cannabis products. Growers, producers, and retailers rely on various independent QC laboratories to perform accurate and efficient analyses to determine potency, chemovar, and aroma, and ensure the product does not contain any harmful contaminants. For those entering the cannabis QC laboratory space, careful planning is essential to ensure a successful operation.
Choosing the Right Instrument for Analysis
Instrument selection is often based on the characteristics of the compound of interest. Cannabinoids, terpenes, heavy metals, and other contaminants may require different instrumentation for accurate identification and quantification.
Cannabinoid quantification for potency testing is often achieved using HPLC (high-performance liquid chromatography), UHPLC (ultra high-performance liquid chromatography), LCMS (liquid chromatography-mass spectrometry) and LC-MS/MS (liquid chromatography-tandem mass spectrometry). Since these methods do not heat the samples, they may be used to quantify THC and CBD precursors (tetrahydrocannabinolic acid and cannabidiolic acid) to obtain total THC and CBD values. LC-MS/MS is also suitable for testing residual pesticides and mycotoxins, with either electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI) methods. This approach offers a high degree of selectivity and sensitivity, and often requires minimal sample preparation.
Terpenes account for the unique aromas associated with different cannabis chemovars, and produce a synergistic effect with cannabinoids. Analysis with HPLC is challenging, as cannabinoids may interfere with terpene elution. Gas chromatography (GC) has been demonstrated to offer a higher degree of sensitivity, and with the addition of a headspace sampler (HS-GCMS), can be used to effectively target and separate volatile terpenes to produce a clean spectrum. HS-GCMS is also suitable for analyzing residual solvents used to extract cannabinoids and terpenes.
Most states require analysis of heavy metals including arsenic, cadmium, lead, and mercury, and many other states require additional heavy metals testing. ICP-MS (inductively coupled plasma mass spectrometry) is the preferred method for heavy metals analysis. It enables detection of multiple elements simultaneously, with a low detection limit and high sample throughput.
Pathogens including E. coli, Salmonella, and Aspergillus species (A. fumigatus, A. Flavus, A. niger, and A. terreus) pose additional challenges for QC laboratories, as they are not amenable to chromatography. PCR (polymerase chain reaction) and DNA microarray technology enables pathogen detection based on target DNA sequences. These methods require additional instrumentation and expertise.
A moisture balance is also a valuable instrument for cannabis testing laboratories, as analyses require an accurate dry weight. Maintaining a low moisture level (<12%) also helps to prevent mold growth.
Considering Initial and Ongoing Costs
Given the sophisticated instrumentation required, the initial costs associated with equipping a cannabis QC laboratory can be high, even when excluding such expenses as building and personnel costs, standard lab supplies, and rent/taxes. Decision-makers should conduct a thorough review of different instruments and their capabilities to ensure they will best fit the needs of the laboratory.
An important initial consideration is whether to opt for gas or liquid chromatography, and whether a modular or integrated unit is required. While an integrated unit includes all the components necessary to begin sample analysis, a modular unit offers greater versatility. There are also various detection methods to consider. These include UV/Vis detection, in which confirmation of the specific cannabinoid is based on the retention time, and photodiode array (PDA) detection, which allows measuring the entire wavelength simultaneously. Alternatively, a MS-based system provides insight into a compound’s molecular weight and structure, and high-resolution mass spectrometers (HRMS) including Quadrupole Time-of-Flight (Q-TOF-MS) and Matrix Assisted Laser Desorption/Ionization (MALDI-MS) are also available.
The ongoing costs for a cannabis QC laboratory encompass general laboratory operating costs as well as more specific expenses associated with cannabis testing instrumentation. Each method requires specific consumables, such as high-purity gases, reagents, and columns. For example, cannabinoid analysis via HPLC, requires high-purity water, acetonitrile, and a specific analytical column, whereas ICP-MS methods require argon gas, a torch, and cone assembly. It is therefore essential to identify the various consumables and components required for each instrument to aid in the estimation of ongoing operational costs.
Determining Your Return on Investment
The return on investment will vary based on several factors, including an instrument’s throughput (determined by run time and the number of samples analyzed per day), and the expected revenue per sample. Table 1 provides a comparison of estimated ROI for different analyses using Shimadzu chromatography instrumentation.
|Cannabinoids||Terpenes||Heavy Metals||Pesticides and Mycotoxins||Residual Solvents||Moisture|
|Expected revenue per sample (USD)||50||120||75||225||100||20|
|Total run time (min)||10||12||5||12||14||10|
|Expected revenue/week (USD)||12,000||24,000|| 36,000||45,000||17,100||4,800|
|Instrument cost (USD)||HPLC|
|Weeks to break even||3.75||3.8||3.5||8.9||5.3||0.4|
Selecting the appropriate analytical instruments, an-ticipating initial and ongoing costs, and estimating return on investment are a few strategies to ensure the success of a new cannabis QC laboratory. Shimadzu offers a full range of instruments, methods, and expertise to support accurate, efficient cannabis analysis.