Detection of glucose based on the peroxidase-like activity of reduced state carbon dots

•Reduced state carbon dots possess intrinsic peroxidase-like activity.•Reduced state carbon dots can catalytically oxidize TMB by H2O2 to produce a color reaction.•Reduced state carbon dots are applied to glucose detection.

It was found that reduced state carbon dots (r-CDs) possessed intrinsic peroxidase-like activity, and could catalytically oxidize 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2 to produce a color reaction. The effects of temperature, pH, incubating time and the concentration of H2O2 and TMB on catalytic activity of r-CDs were investigated. Finally we calculated the kinetic constant was ca. 0.00729 min−1 and applied r-CDs to glucose sensing by coupling glucose oxidase. As low as 2 µM H2O2 could be detected with a linear range from 0.010 to 0.40 mM via this method. This study offered a simple, sensitive, and high selectivity method for glucose determination even in serum.

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