Department of Chemistry, Western Illinois University, Macomb, IL, 61455, USA.
Department of Chemistry, Western Illinois University, Macomb, IL, 61455, USA.
Anal Chim Acta. 2022 May 15;1207:339827. doi: 10.1016/j.aca.2022.339827. Epub 2022 Apr 11.
The growing popularity of Cannabis sativa L. and its widespread use for medical and recreational purposes have created an urgent demand of accurate and reliable analytical methods to identify and quantify a growing number of cannabinoids. To meet this demand, a liquid chromatography diode array detector (LC-DAD) method has been developed, validated, and applied in analysis of cannabinoids in nine samples of plant materials of marijuana, six samples of marijuana cigarettes, five samples of hemp flowers, one sample of hemp cigarette, and two samples of Δ-tetrahydrocannabinol (Δ-THC) fortified hemp flowers. The method has achieved significant improvements over published methods, which was characterized of 20 targeted cannabinoids, 18 quantified cannabinoids, baseline resolution among quantified cannabinoids, a low limit of quantification (0.02 μg mL), a wide linear range (0.02-25 μg mL or 0.04-50% (w/w)), a unique experiment to track the recovery of sample preparation in real time by spiking abnormal cannabidiol (CBD), and a well-assessed specificity by electrospray ionization time-of-flight mass spectrometry (ESI/TOFMS). Precision and accuracy were assessed using quality control (QC) samples at three concentration levels, i.e., 0.02, 0.5, and 12.5 μg mL, in triplicates with inter-day and intra-day precision of less than 15% relative standard deviation (RSD) and accuracy of less than ±15% relative error, therefore meeting the requirements by the ISO 17025 standards. Additionally, ESI/TOFMS has discovered seven unknown cannabinoids, including one structural isomer of cannabigerol (CBG), one structural isomer of cannabinolic acid (CBNA), four structural isomers of Δ-THC, and one structural isomer of Δ-THC acetate. Furthermore, it uncovered that one of the two samples of Δ-THC fortified hemp flowers contained 5.16% (w/w) Δ-THC, an alarm to the current Δ-THC craze by the public.
大麻素的广泛应用及其在医疗和娱乐方面的广泛应用，催生了对准确可靠的分析方法的迫切需求，以便鉴定和定量分析不断增加的大麻素种类。为了满足这一需求，开发并验证了一种液相色谱二极管阵列检测（LC-DAD）方法，并将其应用于 9 种大麻植物材料样品、6 种大麻烟样品、5 种大麻花样品、1 种大麻烟样品和 2 种 δ-四氢大麻酚（δ-THC）强化大麻花样品中的大麻素分析。该方法与已发表的方法相比有了显著的改进，具有 20 种靶向大麻素、18 种定量大麻素、定量大麻素之间的基线分离、较低的定量下限（0.02μg/mL）、较宽的线性范围（0.02-25μg/mL 或 0.04-50%（w/w））、通过异常大麻二酚（CBD）实时加标跟踪样品制备回收率的独特实验，以及通过电喷雾电离飞行时间质谱（ESI/TOFMS）评估的良好特异性。使用 0.02、0.5 和 12.5μg/mL 三个浓度水平的质控（QC）样品评估精密度和准确度，重复测量三次，日内和日间精密度小于 15%相对标准偏差（RSD），准确度小于±15%相对误差，符合 ISO 17025 标准的要求。此外，ESI/TOFMS 发现了 7 种未知大麻素，包括大麻二酚（CBG）的 1 种结构异构体、大麻酸（CBNA）的 1 种结构异构体、Δ-THC 的 4 种结构异构体和 Δ-THC 乙酸酯的 1 种结构异构体。此外，它还发现 2 种 δ-THC 强化大麻花样品中的 1 种含有 5.16%（w/w）的 δ-THC，这引起了公众对当前 δ-THC 热潮的警惕。
