Electro-polymerized polyacrylamide nano film grown on a Ni-reduced graphene oxide-polymer composite: A highly selective non-enzymatic electrochemical recognition element for glucose

In this study, we have developed a non-enzymatic electrochemical biosensor for glucose, which shows fast response, reproducibility, high selectivity and sensitivity. Reduced graphene oxide (rGO) and Ni-nanoparticles were in situ dispersed in melamine-novolac polymer. The prepared novel Ni-rGO/P composite was used as the working electrode. Polyacrylamide (PAA) nano film was grown for the first time on the Ni-rGO/P substrate via electro-polymerization and used for the selective recognition of glucose. Melamine served as the source of the electro-conductive N heteroatom in the material. Tested using differential pulse voltammetry, PAA-Ni-rGO/P showed remarkable linearity (R-2 = 0.99; S/N ratio = 3) over 0.03-250 mg dL(-1) of glucose concentrations, with high sensitivity (1724.58 mu A mM(-1) cm(-2)) and low detection limit (0.0126 mg dL(-1)). The sensor also exhibited high reproducibility (up to (similar to)500 consecutive tests, RSD < 5%) and a good recovery. With negligible effects of the interfering bio-molecules (uric acid, ascorbic acid, cholesterol, etc.) on the sensor response, applicability of the present sensor was successfully tested (RSD < 6%) in a clinical setting. The approach described in this study can be used to electrochemically grow similar macromolecules as the recognition elements for different biomarkers.