An amperometric glucose biosensor based on PEDOT nanofibers

Abstract

Here we present a simple, low cost approach for the production of PEDOT nanofiber biosensors using simple techniques. Firstly, nanofibers of PEDOT were produced by the chemical vapor polymerization of EDOT on FeCl₃ containing electrospun PAN nanofiber mats. The nanofibers were characterized by SEM, FTIR, CV and conductivity studies, which indicated the formation of homogeneous, porous, electroactive PEDOT nanofibers. The fabrication of biosensors was achieved through the loading of various amounts of GOx on the nanofibers. To uncover their capability, the biosensors were operated under both hydrogen peroxide production and oxygen consumption conditions. For each biosensor current response versus glucose concentration calibration curves were plotted. The sensitivity, linear range, LOD, K_m and I_max values of the biosensors were determined and the stabilities of all the sensors were investigated. The biosensor operating at 0.6 V revealed a lower LOD with a wider linear range, higher stability, good sensitivity and selectivity. For example, the PEDOT-NFs/GOx-3 nanofiber biosensor showed good sensitivity (74.22 μA mM⁻¹ cm⁻²) and LOD (2.9 μM) with a response time of 2–3 s without any interference effects. The PEDOT-NFs/GOx-2 biosensor operating at −0.6 V exhibited extreme sensitivity of 272.58 μA mM⁻¹ cm⁻². Our studies have shown that having good sensitivity, LOD and stability makes these interference-free, easy to construct sensors viable candidates for commercialization.