Development of voltammetric sensors for determination of cocaine and delta-9-tetrahydrocannabinol in samples seized by the police

Abstract

This project aims to develop alternative voltammetric methodologies for the analysis of trace elements of cocaine and D-9-THC (the most potent active principle of marijuana) through printed electrodes, for use in forensic laboratories and crime scenes. The aforementioned substances should be inserted on the electrode surfaces of printed electrodes and the electrochemical behavior of the analytes in question on the surface of these electrodes should be investigated. Standard solutions of the analytes of interest, previously deoxygenated and enriched with electrolyte-carrier, will be added to the surface of the printed electrodes.For the studies of electrochemical behavior, the voltammetric modalities of cyclic sweep, as well as differential pulse and square wave will be used, and the amperometric responses of each analyte, as well as its oxidation and / or reduction potentials should be investigated. Once the optimized conditions of electrochemical response have been defined, as well as the validation tests of the technique, it is intended to perform the determination step of these analytes in samples seized forensic interest, through a partnership already established with the local post of the Institute of Criminalistics.It should be noted that, in the real sample dosing step, the comparison study will be carried out with a conventional technique of previously established methodology, and a portable Raman spectrophotometer, which is requested in this project, should be used.In relation to the disposable printed platforms, the group has commercial electrodes from BVT and Palmsens, as well as currently also develops platforms on microfluidic paper, with impressions made with conductive material. However, in order to carry out the proposed experiments, it becomes crucial to acquire the equipment requested in said application, which is a miniaturized Raman spectrophotometer, with the possibility of transporting the same and subsequent field analysis. (AU)