Electroanalytical determination of cannabinoids in hashish samples for future implementation in electrochemical sensors

Cannabis and its derivates (such as hashish) remains nowadays one of the most commonly used drugs of abuse in Europe, with 8,4% of young adults and adults reporting use in the last year [1]. Its psychotropic effects stem from Δ9-tetrahydrocannabinol (Δ9-THC). Recently, products with low Δ9-THC levels but high cannabidiol (CBD) content have become available on the market, posing new challenges for cannabinoids detection and analysis. Our research group has been working for years on the development of innovative electrochemical sensors for the rapid detection of these analytes [2]. The construction features of SPEs (Screen Printed Electrodes) make them particularly suitable for their use in electrochemical sensors. For this reason, in this work, a specific type of SPEs modified with carbon black were used for the electrochemical determination of the cannabinoids content of real hashish samples. The extraction procedure of the samples and the instrumental parameters (15 mV/s potential scan rate with 50 mV pulse potential, 6 mV step potential, 0.1 s pulse time and 0.4 s interval time) used for the analyses were also optimized. Using the same working conditions, standard solutions at different concentrations of the main cannabinoids present in the hashish extracts were analysed. The analysis of these standard solutions allowed for the construction of specific calibration curves as well as the application of the standard addition method to limit the matrix effect, ensuring the possibility to obtain a quantitative determination of the cannabinoids content in the real samples.