A rapid method for the extraction of cannabionoids from cannabis sativa using microwave heating technique

Abstract

Cannabis sativa and its products (marihuana, hashish and hashish oil) is one of the most used illicit drugs in the world. It is also an agricultural crop so it is important to distinguish between industrial-type and drug-type cannabis by forensic examination of suspected material. Extraction technique is one of the first steps in the laboratory plant material isolation, and therefore the development of new, more efficient method of extraction is desirable. The traditional techniques of extraction of biological active compounds from plant material, such as cannabinoids from cannabis, are based on solvent extraction. These methods are often inefficient in terms of extraction time, amount of solvent, energy consumption and extraction yield. Therefore the importance of continuous development of new, more efficient extraction methods is understandable. In this paper, the short description of cannabis plant and chemical constituents of forensic significance were shown for better understanding. Paper also describes the mechanism of microwave heating and its use in the extraction method through short theoretical background of microwave heating. In addition, examples of application of microwaves for the isolation of some organic compounds from plant material were presented. It is also shown that the microwave extraction can be used in absence of solvent in solvent free microwave technique. The possibility of microwave extraction application in forensic examination of Cannabis sativa is presented by highlighting its simplicity and efficiency.

Forenzička identifikacija aktivnih supstanci iz kanabisa i njenih produkata (marihuana, hašiš, hašiš ulje) sastoji se u određivanju sadržaja glavnog psihoaktivnog kanabinoida Δ9-tetrahidrokanabinola, produkta degradacije kanabinola i nepsihoaktivnog kanabidiola. Tehnika ekstrakcije predstavlja jedan od prvih koraka laboratorijskog izolovanja biljnog materijala, te je stoga, razvoj novih, efikasnijih metoda ekstrakcije izuzetno važan za sprovođenje forenzičkih analiza. Potencijalna alternativa konvencionalnim metodama ekstrakcije jeste ekstrakcija pod uticajem mikrotalasa, odnosno mikrotalasnim zagrevanjem. U ovom radu opisan je mehanizam mikrotalasnog zagrevanja i kroz primere njegove primene u ekstrakciji organskih jedinjenja iz biljnog materijala, istaknute su prednosti ove relativno nove ekstrakcione tehnike u poređenju sa konvencionalnom ekstrakcijom. Opisom jednostavne i brze metode ekstrakcije, mikrotalasnim zagrevanjem, prikazana je mogućnost njene primene u forenzičkoj identifikaciji kanabisa.