Au/graphene quantum dots as sensor for highly sensitive electrochemical determination of glucose.

Diabetes is a metabolic disorder indicated by blood glucose concentrations, and causes with long-term damage and failure of various organs like heart, kidney, eyes, and blood vessels, ... The early and sensitive detection of abnormal glucose level in the blood is very important for proper treatment to reduce many health problems. Graphene quantum dots (GQDs) have become attractive for various applications, particularly in diagnostics, drug delivery, electronic displays, ..., due to its excellent electrical conductivity, biocompatibility, and transparency. Au is a promising semiconductor nanomaterial suitable to help GQDs in increasing the refractive index of the dielectric sensing media, which consequently increases the absorption of glucose. Herein, a simple and eco-friendly method to obtain amino-functionalized Au nanoparticles/GQDs based on directly carbonization of citric acid for the preparation of a glucose sensor was reported. The sensing performance of the obtained nanosensor were tested, using a potentiostat/galvanostat, by cyclic voltammetry.