Graphite-like carbon nitrides as peroxidase mimetics and their applications to glucose detection

g-C3N4 was found to possess intrinsic peroxidase-like activity, and could catalytically oxidize 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2 to produce a color reaction. Using g-C3N4 peroxidase-like catalytic activity and glucose oxidase (GOx), a colorimetric method for glucose detection in serum samples has been developed. The linear range for glucose was from 5 to 100μM (R2=0.9987) and the limit of detection was as low as 1.0μM. The proposed method was applied to detect glucose in serum samples by the naked eyes. •g-C3N4 was demonstrated to catalyze the oxidation of TMB by H2O2 to produce a blue color product.•A colorimetric method for H2O2 was achieved with a limit of detection 0.9μM.•Using g-C3N4 and GOx, a colorimetric method for glucose was developed with a detection limit of 1.0μM.•The visual detection of glucose in serum samples could be realized.