An Abiotic Glucose Indicator System

Abstract

This study reports the development of an abiotic glucose indicator system constructed using a biofuel cell consisting of a colloidal platinum coated gold microwire (Au-co-Pt) anode and a platinum coated gas diffusion electrode (GDE). The electrochemical and polarization characterizations were achieved via cyclic voltammetry and current-voltage measurements. The biofuel cell demonstrated a maximum open circuit voltage ( $\text{V}_{{\mathrm {oc}}}$ ) of 0.38 V and an $\text{I}_{{\mathrm {sc}}}$ of 0.225 mA/cm2 with $\text{P}_{{\mathrm {max}}}$ of 0.022 mW/cm2 when operating in 5 mM concentration. An optical readout circuit comprising a light emitting diode (LED) and an android mobile phone camera application (App.) were integrated to record glucose concentration levels correlating to the blinking frequency of the LED and transmit the recorded data to a smart phone in real time. When operated as a glucose indicator, the system exhibited a good sensitivity of $0.616~\mu \text{A}$ mM−1 and linear dependence with a correlation coefficient of 0.995 and a wide linear dynamic range up to 50 mM. Excellent selectivity towards glucose in the presence of competing and interfering species was demonstrated. The fabricated abiotic glucose indicator system has the potential to serve as a potentiostat-less platform in point-of-care applications.