Development of a Portable and Autonomous Potentiostat for On-site Chemical Analyses

Several electrochemical methods have been developed for promising applications in the field, leveraging the simple and affordable instrumentation involving electrochemistry. Despite this, most still need to prove this capability, as they rely on expensive experimental infrastructure in research settings. Although affordable electrochemical sensor fabrication has significantly developed, the instrumentation aspect hasn’t followed, particularly in the skill set needed to acquire, treat, and interpret data, which is still done by specialized users even when an affordable potentiostat is used. Here we present the development of an affordable potentiostat, using simple components and an Arduino Nano microcontroller board, which can perform several electrochemical methods, including amperometry, cyclic voltammetry, and square wave voltammetry. Further, the program running in the microcontroller can acquire and store the data in its internal memory, process the signal, and interpolate it against a pre-loaded calibration plot, reporting the sample concentration value in an OLED screen. An internal battery powers the potentiostat, and this entire operation is autonomously performed after pressing a single button, allowing untrained users to perform complex measurements in remote locations. The potentiostat is coupled with a fully 3D-printed integrated electrode system, encompassing the working, pseudo reference, and counter electrode, which can be further modified for selective electrochemical sensing. The combination of an affordable potentiostat with a fully 3D printed sensor allows the entire ensemble to be fabricated in a maker space or a “hobbyist garage,” making this a legitimate, affordable platform for performing electrochemical methods at less than $ 72 per equipment + sensor. With the autonomous operation, this affordable instrumentation will help bring many developments in “field-deployable” electrochemical sensing to fruition.