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Title: Quantitative analysis of cannabinoids by zone heat-assisted DART-MS with in-situ flash derivatization
Accurate quantitation of cannabinoids, particularly Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), is essential for regulatory compliance, forensic investigations, and cannabis product development. Traditional methods, such as liquid chromatography (LC) and gas chromatography (GC) coupled with mass spectrometry, provide reliable results but are time-consuming and resource-intensive. This study introduces a rapid and high-throughput analytical method using zone heat-assisted direct analysis in real time mass spectrometry (DART-MS) combined with in-situ flash derivatization. The method employs trimethylphenylammonium hydroxide (TMPAH) for efficient derivatization, allowing for the differentiation of THC, CBD, and their acidic precursors, Δ9-tetrahydrocannabinolic acid (THCA) and cannabidiolic acid (CBDA). A custom heated transfer zone was implemented to enhance derivatization efficiency and reduce carryover effects. The method was optimized for reagent concentration and gas stream temperature, achieving high specificity by minimizing interference from isomeric cannabinoids. Validation studies demonstrate good accuracy (relative error within ±15.9 %) and precision (relative standard deviation ≤15 %), with limits of quantitation of 7.5 µg/mL for THC/CBD and 0.5 µg/mL for THCA/CBDA. Comparative analysis of cannabis samples showed a strong correlation with reference LC/MS results, highlighting the reliability of the proposed method. DART-MS offers a significant time advantage, requiring only 10 s per analysis, making it a promising tool for high-throughput screening of cannabis samples in forensic laboratories.  more » « less
Award ID(s):
2216092
PAR ID:
10650056
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Forensic Chemistry
Volume:
42
Issue:
C
ISSN:
2468-1709
Page Range / eLocation ID:
100641
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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