Electrochemical glucose biosensor based on biosynthesized silver nanoparticles and polyvinylpyrolidone modified graphite electrode

In the present work, we have biosynthesized silver nanoparticles (AgNPs) using leaf extract of Euphorbia geniculata and successfully deposited them onto the polyvinyl pyrolidone (PVP) modified graphite electrode (Gr/PVP). The resulting electrode is used as a matrix for the immobilization of glucose oxidase (GOx) enzyme. The immobilized electrode (Gr/PVP/AgNPs/GOx) is characterized by scanning electron microscopy and its performance is evaluated and optimized using cyclic voltammetry and differential pulsevoltammetrictechniques. Under neutral pH conditions, at room temperature, the developed Gr/PVP/AgNPs/GOx sensor showed excellent electrocatalytic activity towards the oxidation of glucose. Further, it is used for the determination of glucose in the concentration range of 0.1-7 mM with a detection limit of 0.15 µM and sensitivity of 29.72 µA mM-1 cm-2. In addition, the response of GOx biosensor is found to be uninfluenced by some common possible interferents. The findings of present work are significant and imply potential applications for biosynthesized AgNPs as effective, non-toxic biocompatible sensor fabrication materials. Copyright © 2018 VBRI Press.