A thumb-size electrochemical system for portable sensors.

To enable electrochemistry-based sensors to be applied under size and cost sensitive conditions, we developed a thumb-size electrochemistry instrument system (MiniEC) with integrated components including an electrochemical sensing interface, signal transduction, amplification, filtering, processing and transmission with a cost of around only $15. We showed its potential application for electrochemical studies and on-site environmental monitoring in a wide range of environments such as laboratory, household, countryside, industry or wild settings. By using the MiniEC with screen printed electrodes, the LOD (limit of detection) for Cd2+ and Pb2+ is as low as 1 μg L-1 and 0.5 μg L-1, respectively.