Gold nanoparticle modified conducting polymer of 4-(2,5-di(thiophen-2-yl)-1H-pyrrole-1-l) benzenamine for potential use as a biosensing material

Gold nanoparticle (AuNP) modified conducting polymer of 4-(2,5-di(thiophen-2-yl)-1H-pyrrol-1-yl)benzenamine (SNS-NH2) was used as the biosensing platform for glucose analysis. Electrochemical measurements were carried out by following the consumed oxygen due to the enzymatic reaction of glucose oxidase (GOx) at −0.7 V vs Ag/AgCl. Optimisation of pH, enzyme loading, stability experiments were carried out. Effect of NP was investigated by monitoring the signal responses at different AuNP sizes and amounts. A linear relation of y = 1.597x + 0.264 (R2 = 0.993) was found for glucose concentrations between 0.002 and 5.0 mM. The analytical characteristics of the system were also evaluated for glucose determination in flow injection analysis (FIA) mode. Finally, the system was checked for glucose detection on real samples.