Cannabigerolic acid

Eight of the 10 cannabinoid analytes [∆⁹-THC, CBN, cannabigerol (CBG), cannabigerolic acid (CBGA), ∆⁹-tetrahydrocannabinolic acid A (∆⁹-THCA), ∆⁹-tetrahydrocannabivarin (∆⁹-THCV), 11-OH-∆⁹-THC, and 11-nor-9-carboxy-∆⁹-THC] and the internal standard (IS; ∆⁹-THC-D₃) were obtained as certified reference materials (CRMs) manufactured by Cerilliant (Round Rock, TX). The 8β,11-diOH-Δ⁹-THC metabolite was obtained from ElSohly Laboratories, Inc. (Oxford, MS). Cannabichromene (CBC) was obtained as a CRM from Cayman Chemical (Ann Arbor, MI). When not in use, concentrated stock solutions of these agents and working solutions made therefrom were stored at – 20 °C.
Acetonitrile, formic acid, methanol, and n-hexane were purchased from Thermo Fisher Scientific and were of LC/MS grade. Ethyl acetate (Acros Organics) was purchased from Thermo Fisher Scientific and was of spectroscopy grade (> 99.5%). High purity water (18.2 MΩ) required for preparing the mobile phase and for sample extraction was produced using an EMD Millipore Simplicity water purification system. When not in use, these agents were stored at room temperature (20–25 °C). Nitrogen (N₂), supplied as a cryogenic liquid in a 230L dewar at a purity of 99.998%, or as compressed nitrogen gas at a purity of 99.999% in T-type cylinders, was obtained from Praxair (Danbury, CT).

Certified cannabinoid reference standards (at 1 mg/mL in methanol) including cannabidiolic acid (CBDA), cannabigerolic acid (CBGA), cannabigerol (CBG), CBD, tetrahydrocannabivarin, cannabinol (CBN), Δ⁹-THC, cannabichromene (CBC), cannabidivarin (CBDV), and Δ⁹-tetrahydrocannabinolic acid-A (THCA) were purchased from Cerilliant (Round Rock, TX). Second-source standards of CBN, CBD, and Δ⁹-THC were from Restek (Bellefonte, PA). CBD hemp oil was purchased from HempMeds (Poway, CA). Norgestrel, 4-pentylphenyl 4-methylbenzoate (PPMB), ammonium formate, formic acid, and sesame oil were from Sigma-Aldrich (St. Louis, MO). Medium-chain triglyceride (MCT) oil was from Warner Graham (Cockeysville, MD). Propylene glycol was from J.T. Baker (Central Valley, PA). Ammonium formate, formic acid, methanol, acetonitrile, and water were HPLC grade. All other reagents used were analytical grade. Bulk cannabis plant material was obtained from the National Institute on Drug Abuse (NIDA), National Institutes of Health, Bethesda, MD.

Methanol, acetonitrile, ammonium formate and formic acid (98%) were HPLC grade. Water was deionized and purified to 18.2 MΩ using a Barnstead Smart2Pure nanopure system (Thermo Scientific). Cannabinoid standards for quantification were purchased from Cerilliant Corp. (Round Rock, TX) for tetrahydrocannabinolic acid (THCA), THC, cannabidiolic acid (CBDA), CBD, cannabigerol (CBG), cannabichromene (CBC), tetrahydrocannabivarin (THCV) and cannabinol (CBN), Δ8-THC, cannabidivarinic acid (CBDVA), cannabidivarin (CBDV), cannabigerolic acid (CBGA) and cannabicyclol (CBL). All standards were provided as 1.0 mg/mL solutions in either methanol or acetonitrile.

Commercially available standards (purity >98%) for cannabichromene (CBC), cannabicyclol (CBL), CBD, cannabidiolic acid (CBDA), cannabidivarin (CBDV), cannabigerol (CBG), cannabigerolic acid (CBGA), cannabinol (CBN), delta-8-tetrahydrocannabinol (Δ-8-THC), Δ-9-THC, THCA, and tetrahydrocannabivarin (THCV) were obtained from Cerilliant (Round Rock, TX, USA). Additionally, deuterated internal standards (purity >98%) (IS) delta-9-tetrahydrocannabinol-D3 (Δ-9-THC-D3) and 11-nor-9-carboxy-Δ-9-THC-D9 (11-nor-9-COOH-Δ-9-THC-D9) were also obtained from Cerilliant (Round Rock, TX, USA). LC-MS grade water, methanol, and formic acid were sourced from Fisher Scientific (Fair Lawn, NJ, USA). Commercially available hops, Humulus lupulus, were obtained from BioKoma (Old Mill Creek, IL, USA).

Stock methanolic solutions (1.0 mg/mL) of cannabidiol (CBD), cannabigerol (CBG) and cannabinol (CBN), as well as stock acetonitrile solutions (1.0 mg/mL) of cannabidiolic acid (CBDA) and cannabigerolic acid (CBGA), were purchased from Cerilliant Corporation (Round Rock, TX, USA).
Stock 2-propanol solutions (1.0 mg/mL) of α-pinene, β-pinene, β-myrcene, limonene, linalool, β-caryophyllene, α-humulene, caryophyllene oxide and trans-nerolidol were obtained from Agilent Technologies (Santa Clara, CA, USA).
Acetonitrile (ACN), formic acid (HCOOH), n-hexane, methanol (MeOH), 2-propanol and methyl-octanoate were purchased from Sigma Aldrich s.r.l. (Milan, Italy). Water (H₂O) was purified using a Milli-Q Plus185 system from Millipore (Milford, MA, USA).
Extra virgin olive oil was of European Pharmacopoeia grade. CBD powder (>99%) and hemp female inflorescences (Kompolti variety), listed within the EU database of admitted agricultural species, were purchased from Materia Medica Processing (Bolzano, Italy).