Positively-charged gold nanoparticles as peroxidiase mimic and their application in hydrogen peroxide and glucose detection

Positively-charged gold nanoparticles possess intrinsic peroxidase-like activity, and can catalyze oxidation of the peroxidase substrate 3,3,5,5-tetramethylbenzidine (TMB) by H2O2 to develop a blue color in aqueous solution, thus providing a simple approach to colorimetric detection of H2O2 and glucose.