General Analytic Cannabis Testing Techniques

Today’s manufacturers and well-advised consumers are interested in multiple chemical aspects of their cannabis plant and product. Cannabis laboratories assist manufacturers to meet state regulations by identifying potentially harmful residual solvents, pesticides, and heavy metals levels. Labs also identify desired, cannabinoid and terpene profiles. Cannabinoids are the primary psychoactive compounds in cannabis products, while terpenes are additional plant compounds that enhance the experience of cannabis consumption. Retailers and producers use this information to recommend specific strains and other products to their customers.

What analytic techniques are used to make these determinations?

Gas Chromatography (GC), High Performance Liquid Chromatography (HPLC), and Mass Spectrometry (MS) are important analytical techniques used in the testing of cannabis and cannabis products.

GC is a technique used to separate and analyze volatile compounds based on their physical and chemical properties. Volatile compounds have a high vapor pressure, low water solubility, and easily evaporate at room temperature. GC may be paired with Flame Ionization Detector (FID); during the process, a carrier gas is mixed with hydrogen, and the outflow of compounds is burned by a flame that is surrounded by air and an oxygen-rich environment. The ions formed in the flame are measured by the FID to classify their parent compounds.

HPLC is a technique used to separate and analyze compounds that are soluble in specific, liquid solvents. HPLC has two phases, a stationary and a mobile phase. The stationary phase consists of fixed packing material, often called resin, which is in a steel tube called the column. As the name suggests the mobile phase moves from the storage reservoir flasks and is pumped through the column by the HPLC pump. As the sample is separated based on the resonance (hold) time within the column, a UV detector monitors the output, to quantify cannabinoid abundance. HPLC is a widely accepted method for cannabis and hemp potency testing providing accurate, consistent analysis.

MS is often used in conjunction with GC or HPLC to identify and quantify the components of a mixture. This analytic tool measures the mass-to-charge ratio (m/z) of the molecules present in a sample utilizing three components: an ionization source, mass analyzer and an ion detection system. Ionization is the process where molecules are converted to gas ions. The resulting ions are separated based on their m/z by a mass analyzer, such as a quadrupole or a time-of-flight (TOF) analyzer. The separated ions are then detected by an electron multiplier and the resulting mass spectrum is used to identify the components of the sample. Mass Spectrometry is often used in conjunction with GC or HPLC to identify and quantify trace contaminants, such as pesticides or heavy metals.

Through Cannabis testing, cultivators and consumers can medicate with ease knowing the precise contents of their Cannabis products. BK Laboratories uses GC, HPLC, MS and other testing techniques to ensure the quality and safety of a variety of Cannabis Products.

Dana Neverdousky, MT(ASCP) & Veronica Martinez: March 2023