Highly Sensitive Electrochemical Cholesterol Biosensor based on Graphene-ZnS Modified Carbon Paper Electrode

Abstract

In this study, we present a new and straightforward graphene-zinc sulfide (ZnS) nanocomposite that we've successfully created for use in a carbon paper-based cholesterol biosensor. By integrating ZnS nanoparticles onto graphene sheets, we've significantly enhanced the electrocatalytic performance of the electrode, which boosts the sensitivity of the cholesterol biosensor. We carried out a comprehensive analysis of the nanocomposite's structure and components using techniques like XRD, SEM, and TEM. For detecting cholesterol, we immobilized cholesterol oxidase onto the ZnS/G modified carbon paper electrode. Our cyclic voltammetry (CV) analysis indicated that there’s direct electron transfer happening between the enzyme and the electrode. The biosensor we developed showcased a quick response time, impressive sensitivity, a wide linear detection range, and a low detection limit. Plus, the ZnS/G modified carbon paper electrode proved to be highly selective, consistently reproducible, and stable for over a month.