An In-depth Study Evaluating the Determination of CBD, Δ9-THC, Δ8-THC, and 25 Additional Cannabinoids in Cannabis Concentrates by Liquid Chromatography with Absorbance Detection

Published

December 15, 2025

Author(s)

Walter Wilson, Arianna Romares, STEPHEN GOLDMAN

Abstract

Cannabis revenue has risen in the United States (US) from $16.5B in 2018 to $45.4B in 2025 [1], which can be attributed to the legalization of hemp in 2018 with the passage of the Agricultural Improvement Act of 2018 (2018 Farm Bill) and the surge of Cannabis-derived finished products such as Cannabis concentrates and edibles. Hemp was defined as any Cannabis sativa plant having a Δ9-tetrahdrocannabinol (Δ9-THC) of ≤ 0.3 % on a dry weight basis. The legalization of higher THC products has continued to increase. As of April 2025, medical marijuana is legal in 41 states, and recreational marijuana is legal in 24 states (and the District of Columbia). After the passage of the 2018 Farm Bill, there was a significant increase in hemp grown in the US, resulting in the supply outweighing the user demand. As a result, scientists developed a process for the synthesis of Δ8-tetrahydrocannabinol (Δ8-THC), Δ10-tetrahydrocannabinol (Δ10-THC), and other cannabinoids from hemp with cannabidiol (CBD). However, these synthetic processes usually produce a combination of isomeric cannabinoids. One of the more common forms of these finished products is called Cannabis concentrates, which include but are not limited to oils, vapes, waxes, distillates, and isolates. The Chemical Sciences Division (CSD) at the National Institute of Standards and Technology (NIST) previously developed an analytical method for the determination of CBD, Δ9-THC, and other cannabinoids in one form of concentrates, oils, by liquid chromatography (LC) with a photodiode array (PDA) detector for ultraviolet absorbance detection. Hemp oils are diluted with methanol and shaken for 15 min using routine laboratory equipment. This publication expands the LC-PDA method to include Δ8-THC-based hemp oils and CBD-based hemp vape products to re-evaluate its performance for an expanded range of Cannabis samples. The results presented here highlight that other cannabinoids are often detected in these samples, leading to potential chromatographic issues for the accurate measurements of Δ9-THC. NIST CSD collaborated with Kaycha Labs in 2024 to better understand the concentrates currently available in the Cannabis industry.

Citation

Chromatographia

Pub Type

Journals

Download Paper

https://doi.org/10.1007/s10337-025-04464-x

Local Download

Keywords

Hemp, Concentrates, CBD, Δ-9-Tetrahydrocannabinol, Δ-8-Tetrahydrocannabinol, Liquid Chromatography

Citation

Wilson, W. , Romares, A. and Goldman, S. (2025), An In-depth Study Evaluating the Determination of CBD, Δ9-THC, Δ8-THC, and 25 Additional Cannabinoids in Cannabis Concentrates by Liquid Chromatography with Absorbance Detection, Chromatographia, [online], https://doi.org/10.1007/s10337-025-04464-x, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=960389 (Accessed January 13, 2026)