A study on characteristic and reliability of fabricated microfluidic three electrodes sensor based on randle-sevcik equation

A simple fabrication method on wet etching and thermal evaporator had been used to fabricate microfluidic three gold (Au) electrodes assembled with polydimethylsiloxane (PDMS) was reported in the present work. In this work, we studied the suitable size of electrode area that can fulfill the Randle-Sevcik equation for reversible redox process. The voltammograms of 0.01 M K₃Fe(CN)₆ in 0.1M KCl at 1.04 mm² electrode area demonstrates the current peak ratio of unity thus suitable to be further developed as a three electrode sensory system with Ag/AgCl reference electrode. The plotted graph for peak current vs electrode area satisfied the Randle-Sevcik equation as well. Cyclic Voltammetry (CV) analysis proved that the fabricated sensor was reliable in the range of 24 hours at the room temperature of 25°C.