Use of voltammetric and chemometric tools to develop a sensor in forensic chemistry

Abstract

The large number of drug seizures has required the development of electrochemical sensors and new analytical techniques involving portable sensors. Here, we have studied cocaine hydrochloride oxy-reduction on the surface of carbon paste electrodes chemically modified with [VIIO(salen)], and we have evaluated these electrodes as voltammetric sensors for forensic purposes. The modified working electrode for cocaine hydrochloride analysis presented the sensitivity was 1.2 µmol.L−1, and the mean limits of detection and quantification were 0.31 and 1.03 µmol.L−1, respectively. As for the possible interferents, the investigated analytes exhibited similar electrochemical activity, with different sensitivities. Supervised classification of the data for the detection of analytes by the SIMCA chemometric method revealed that the voltammetric methodology predicted cocaine in real samples seized by the police more effectively than the other analytes. Thus, the developed voltammetric sensor has potential use in forensic investigations.

Keywords

• Cocaine
• DFT method
• Drugs
• SIMCA
• Voltammetric sensor