Mini-Potentiostat for Low Power Chemical Sensing of Graphene-Carbon Paste Lab on a Chip

This research studied the development of mini-potentiostat for portable electrochemical measurement. The mini-potentiostat was fabricated for analysis of electrochemical values with substances in low concentrations to use with lab on a chip. The mini-potentiostat was designed by using electronic circuits and fabricated from integrated circuits and controlled by microcontrollers. The lab on a chip was designed to be T-shaped and uses digital microfluidics for acting on microfluid to move the liquid droplets to electrochemical sensor of lab on a chip. The sensor consists of screen-printing electrodes: a graphene-carbon paste working and counter electrodes and a silver/silver chloride paste reference electrode. The electrochemical electrodes were fabricated by screen printing methods. The mini-potentiostat was calibrated to test for electrochemical sensor. For analysis, the lab on a chip was tested using low concentration, using potassium hexacyanoferrate and varying concentration of minimal reagent consumption from 200 mM to 1000 mM with increment of 200 mM. This mini-potentiostat can distinguish the concentration of substances with low concentrations effectively