Classification of Various Marijuana Varieties by Raman Microscopy and Chemometrics

Abstract

The Raman analysis of marijuana is challenging because of the sample’s easy photo-degradation caused by the laser intensity. In this study, optimization of collection parameters and laser focusing on marijuana trichome heads allowed collecting Raman spectra without damaging the samples. The Raman spectra of Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN) standard cannabinoids were compared with Raman spectra of five different types of marijuana: four Sativa varieties (Amnesia Haze, Amnesia Hy-Pro, Original Amnesia, and Y Griega) and one Indica variety (Black Domina). The results verified the presence of several common spectral bands that are useful for marijuana characterization. Results were corroborated by the quantum chemical simulated Raman spectra of their acid-form (tetrahydrocannabinol acid (THCA), cannabidiol acid (CBDA)) and decarboxylated cannabinoids (THC, CBD, and CBN). A chemometrics-assisted method based on Raman microscopy and OPLS-DA offered good classification among the different marijuana varieties allowing identification of the most significant spectral bands.

Cannabis recreativo: Perfil de los cannabinoides presentes en muestras de marihuana suministradas por población consumidora

“…Teniendo en cuenta las concentraciones de THC encontradas en las diferentes muestras analizadas y de acuerdo a la evidencia académica existente, las variedades de marihuana circulante en la ciudad y que presentaron altos contenidos de THC (mayor a dos dígitos) son predominantemente las clasificables como creepy, para distinguirlas de las variedades convencionales; "la creepy posee un porcentaje de THC mayor (entre el 10% y el 25%) al de la variedad regular, además de que permite dos o más cosechas al año, que incrementa su rentabilidad, donde la mayor cantidad de THC se debe a modificaciones genéticas" (53) . Este fenómeno se ajustaría a las tendencias continentales por incrementar el nivel de THC en la marihuana en países productores como Paraguay, Uruguay, México, Costa Rica y Colombia (53) .…”

“…El THC, como constituyente principal de la marihuana circulante en Medellín, se ajusta a las tendencias y preferencias de productores y consumidores a nivel continental. La literatura académica y los resultados de la investigación evidenciarían una confluencia entre las variedades genéticamente modificadas (creepy) para obtener mayores niveles de THC y el incremento en la propensión a un mayor consumo; dicho de otro modo, esta confluencia de oferta y demanda mostraría una inclinación por efectos depresores más fuertes sobre el sistema nervioso de los consumidores por medio de dosis más potentes (53,56) .…”

Repositioning Cannabinoids and Terpenes as Novel EGFR-TKIs Candidates for Targeted Therapy Against Cancer: A virtual screening model using CADD and biophysical simulations

“…[ 1 , [18] , [19] , [20] ]. There are several categories of cannabis, the most important of which is the one based on the rate of THC and CBD and CNB [ 21 ]. The higher the THC level, the more the product belongs to the dope class, while the higher the CBD and CNB level, the more the product belongs to the cannabinoid class [ 22 , 23 ].…”

OpenPCA and Raman mapping to decipher complex spectral datasets from multi-component samples: application to cannabinoids and cannabis trichomes

“…Despite the medicinal and economic significance of trichomes, cannabinoid levels, chemical profile, and its distribution in the trichomes remain uninvestigated and poorly understood [6]. To analyse the trichomes and to extract their chemical composition, a powerful non-destructive Raman spectroscopy technique was adopted, but no systematic information was reported on the spatial distribution of the chemical species in the plant [7,8].…”