Senior Honors Projects, 2020-current

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Date of Graduation




Document Type


Degree Name

Bachelor of Science (BS)


Department of Chemistry and Biochemistry


Daniel M. Downey

Debbie L. Mohler

Chrisi A. Hughey


Cannabis sativa L. is a flowering plant used for recreational and industrial purposes that produces a class of compounds called cannabinoids. Industrial hemp is a strain of Cannabis sativa L. that has been propagated to have a low Δ 9 tetrahydrocannabinol (Δ9THC) and a high cannabidiol (CBD) content. With recent advancements in legislation, farms are now growing hemp for fiber, CBD production and other hemp derived product purposes but crops risk being destroyed if THC content levels exceed the current maximum legal limit of 0.3%. For the present study hemp samples were dried, ground, extracted with various alcohols, filtered, and assayed by ultra-High Pressure Liquid Chromatography with ultraviolet detection (uHPLC-UV) and Gas Chromatography with flame ionization detection (GC-FID) for ten cannabinoids, with primary focus on THC and CBD. Three replicates were done for each sample strictly following published protocols. We have found that the results of analyses vary considerably due to variations in cannabinoid content in plant biomass, different hemp varieties, growing location and before/after drying. The random sampling procedure, the heterogeneity of the crop and large standard deviations for analyses affected results. We have statistically evaluated data and conclude that large sample standard deviations are intrinsic with the protocols. These may lead to crops that are actually within the legal limit being destroyed by regulators. As a result, it was concluded that either 0.3% THC should not be applied as an absolute value for legality but should be associated with sample standard deviation for replicates of analyses, or the absolute criterion be raised to 0.5%.



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