Fast Discrimination of Marijuana using Automated High-throughput Cannabis Sample Preparation and Analysis by Gas Chromatography-Mass Spectrometry.
In the United States, federal law and many state laws differentiate between marijuana and industrial hemp through delta-9-tetrahydrocannabinol (THC) levels, whereby the latter is defined as ≤0.3 percent THC on a dry weight basis. Many traditional cannabis identification methods employed by crime laboratories cannot accurately determine total THC quantities in accordance with federal and state regulations, or do so with increased time, labor, and risks of instrument damage. In order to quickly distinguish positive marijuana samples, a method was developed to identify plant material with a total THC level >1%. This novel, automated dispersive pipette extraction (DPX) method uses tip-based technology and an automated liquid handler to enable fast, hands-free selective isolation of THC and its precursors for downstream gas chromatography-mass spectrometry (GC-MS) analysis. The workflow proceeds with no repetitive manual effort and reduced need for instrument maintenance while enabling crime labs to legally identify marijuana through the detection of total THC above 1%. Recovery of THC using the DPX extraction method was 93% at 30 µg/mL and 78% at 500 µg/mL. Similarly, THCA-A recovery was 100% at 30 µg/mL and 74% at 500 µg/mL. Samples evaluated in a blind study (proficiency, hemp, and nonprobative case samples) were all accurately identified as greater than or less than 1% THC, with samples containing <1% THC being identified as « cannabis » and subjected to more discriminative analysis as needed.
Keywords: cannabidiol; cannabis; drug identification; gas chromatography-mass spectrometry; hemp; marijuana; tetrahydrocannabinol.
© 2020 American Academy of Forensic Sciences.
- ElSohly MA, Gul W. Constituents of cannabis sativa. In: Pertwee R, editor. Handbook of cannabis. Oxford, U.K.: Oxford University Press, 2014;3-22. https://doi.org/10.1093/acprof:oso/9780199662685.003.0001
- ElSohly MA, Mehmedic Z, Foster S, Gon C, Chandra S, Church JC. Changes in cannabis potency over the last two decades (1995-2014): analysis of current data in the United States. Biol Psychiatry 2016;79(7):613-9. https://doi.org/10.1016/j.biopsych.2016.01.004
- Schedules of Controlled Substances. 21 U.S. Code Controlled Substances Act, Section 812, https://www.deadiversion.usdoj.gov/21cfr/21usc/812.htm (accessed March 14, 2019).
- Agricultural Act of 2014. Pub. L. No. 113-79, 2014. https://www.congress.gov/bill/113th-congress/house-bill/2642/text (accessed March 14, 2019).
- Agriculture Improvement Act of 2018. Pub. L. No. 115-334, 2018. https://www.congress.gov/bill/115th-congress/house-bill/2/text (accessed March 14, 2019).
L’article Fast Discrimination of Marijuana using Automated High-throughput Cannabis Sample Preparation and Analysis by Gas Chromatography-Mass Spectrometry. est apparu en premier sur Cannabis Belgique.