Forensic Electrochemistry: Electrochemical Analysis of Trace Methamphetamine Residues on Household Surfaces

Illicit methamphetamine is known to be the most manufactured amphetamine-type stimulants worldwide. Relatively simple manufacturing procedure had resulted in the creations of manufacturing sites in a variety of premises and structures, deserving forensic investigation. Therefore, this study was aimed to develop an electrochemical detection technique to determine the residual methamphetamine contamination on various surfaces. Carbon materials, namely graphene oxide, graphene nanoplatelets, graphene ink, and glassy carbon microsphere modified glassy carbon electrode were used in detecting methamphetamine by differential pulse voltammetry (DPV). The surface morphology modified electrode was characterised and its electrochemical behaviour was determined. Under optimal conditions, the calibration curve showed bilinear in the concentration range of 1−40 μ M and 40−120 μ M with good precision and accuracy. The limit of detection was determined to be 0.3 μ M. Graphene oxide modified electrode coupled with DPV successfully detected the residual methamphetamine on four household surfaces, including glass, stainless steel, plastic, and varnished wood with recoveries greater than 82%. To conclude, a novel electrochemical detection technique for the presence of methamphetamine was successfully developed to be applied in clandestine laboratory settings. It would be beneficial to assist the forensic investigation, especially for those forensic evidence recovered from suspicious and suspected clandestine laboratories.