Influence of LiClO 4 concentration on 1-D polypyrrole nanofibers for enhanced performance of glucose biosensor

Abstract

In the present work, a template-free single-step fabrication of Lithium perchlorate (LiClO 4 ) doped 1-D Polypyrrole nanofibers network (PNN) (without using electrospinning) toward glucose biosensing application has been reported. The PNN with different concentrations of LiClO 4 was grown over the Platinum coated glass substrate by electropolymerization method and utilized as a support matrix for immobilization of enzyme. The effect of LiClO 4 concentration on glucose biosensor performance has been demonstrated for the first time. The modification in morphology and reduction in charge transfer resistance of PNNs by varying LiClO 4 concentration were found to play a significant role in the improved figure of merits of the biosensor. Among all the types of as-fabricated PNN electrodes (prepared by using different concentrations of LiClO 4 viz. 1, 10, 50, and 70 mM) the best response was obtained corresponding to highest LiClO 4 concentration. The enzyme loading and charge transfer resistance were drastically improved by approximately three folds owing to the higher surface area and improved conductivity of PNN electrodes thereby resulting in ten-fold increment in sensitivity. The as-prepared biosensor showed the highest sensitivity of 4.34 mA-cm-2-M-1 and a linear range of 0.1-4.6 mM with good stability and high selectivity for glucose detection. © 2018 The Electrochemical Society.