Methods for determination of ∆9-tetrahydrocannabinol content in seeds of hemp by gas chromatography method: analysis and scientific justification
Abstract
Cannabis (Cannabis sativa L) has been an important part of the well-being of the population for many centuries. This plant is a bast and oilseed crop that is characterized by specific biological and unique consumer properties. However, hemp plants also have medicinal and narcotic properties. Cannabis plants can excrete secretions that contain cannabinoids. The psychotropic effect of the narcotic drug cannabis is the result of the complex action of all cannabinoids, although only some of them have a psychotropic effect in its pure form. These include, first, delta-9-tetrahydrocannabinol (∆-9THC), which has a major psychotropic effect and is able to selectively bind to cannabinoid receptors in certain brain structures. In this regard, the development of simple and effective methods of detection (∆-9-THC) in hemp plant seeds is an urgent issue. The article considers the analysis of existing methods of liquid-liquid extraction of ∆-9-THC from hemp seeds with their subsequent approbation and improvement for separation of interfering fractions, first of all fats (oils), and with the subsequent identification of ∆-9-THC by gas chromatomass spectrometry with mass-selective detection. Some methods of liquid-liquid extraction of hemp seeds and comparison of the obtained results are given. To solve this goal, seeds collected from technical hemp of the Glyana variety, cultivated from plants of the genus of hemp for industrial purposes, allowed by the legislation of Ukraine, are collected from varieties of hemp plants in dried straw whose content of ∆-9-THC does not exceed 0.08 percent. It has been found that the method with the use of acetonitrile as an extracting, followed by washing with hexane, most meets the goal of the study, namely to detect ∆-9-THC in small quantities, especially in hemp seeds. This method of extraction is best suited due to the lowest amount of co-extractives found on the chromatogram, primarily fats and fat hydrolysis products, namely higher carboxylic acids (saturated and unsaturated), which may interfere with the study. These studies can be further used to quantify ∆-9-THC in hemp seeds and foods made from hemp seeds, followed by the detection limit (LOD) and the limit of quantification (LOQ) of the substance, which is necessary for further certification of these products and exports. The obtained research results allow to determine the presence of ∆-9-THC in hemp seeds and food products made from hemp seeds
Keywords
∆9-THC; technical hemp; hemp seeds; cannabinoids; extraction; gas chromato-mass spectrometry
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