A unique electro-contact-free sensing for illegal drug methamphetamine determination by electrochemiluminescence based on wireless power transmission technology

The wireless power transfer (WPT) technique is a unique safe electric power supply system. In this study, we designed a simple analytical system that combines electrochemiluminescence (ECL) measurement with WPT for illegal stimulant methamphetamine (MA) detection. The WPT-ECL system, which consists of a commercially available inexpensive driving coil and a commonly available enameled wire, was used to screen MA with an easy procedure. The prototype WPT-ECL measurement system observed a clear ECL response by incorporating an inexpensive rectifying diode, and MA was determined in the range to 500 mu M with the detection limit of ca. 15 mu M (S/N =3). The MA detection protocol under WPT-ECL measurement was characterized; it was expected to be a simple and cost-effective analytical technique without complex circuitry, such as full-wave rectification. The proposed WPT-ECL system was applied to an actual urine sample. MA addition and recovery experiments on three volunteer urine samples showed good reproducibility with an RSD of less than 6 %, resulting in good agreement with the LC-MS results. The WPT-ECL system was expected to enable non-specialist investigators to simple detection procedures of MA, with the aim of practical application to forensic toxicology analytical scenes.