Biocompatible polypyrrole-block copolymer-gold nanoparticles platform for determination of inosine monophosphate with bi-enzyme biosensor

Inosine monophosphate (IMP) is considered to be an important constituent in the formation and development of meat flavor. In this paper, a bi-enzyme biosensor system for determination of IMP was developed to evaluate the freshness and quality of stored muscles. More details of preparing for polypyrrole-Pluronic F127-gold nanoparticles (PPy-F127-Au NPs) and immobilizing bi-enzyme (peroxidase and 5′-nucleotidase) on PPy-F127-Au NPs modified glassy carbon electrode (GCE) were presented. The electrochemical behaviors of the bi-enzyme biosensor were analyzed, and the concentration of IMP was determined based on the bi-enzyme biosensor response. The results of linear sweep voltammetric (LSV) and square wave voltammetry (SWV) indicated that the catalytic reaction was occurred favorably on the surface of the bi-enzyme biosensor, with a wide detection range (0.05–15   g/L) and a low detection limit of 3.85   ng/mL. The good anti-interference ability, stability and repeatability of this biosensor were also proved. The analytical results by the biosensor system did correlate well with those obtained by liquid chromatography.