Visual detection of blood glucose based on peroxidase-like activity of WS2 nanosheets

Tungsten disulfide (WS2) nanosheets were discovered to possess intrinsic peroxidase-like activity and catalyze the peroxidase substrate 3,3′,5,5′-tetramethylbenzidine (TMB) to produce a color reaction in the presence of H2O2. Based on this finding, a colorimetric method and a portable test kit for the visual detection of blood glucose have been developed by using glucose oxidase (GOx) and WS2 nanosheets-catalyzed reactions. The linear range for glucose was ranged from 5 to 300 μM (R2=0.999) with the detection limit of 2.9 μM. The portable test kit was successfully evaluated glucose levels in serum samples from normal persons and diabetes persons by the observable color change from pale yellow to yellow–green, blue–green.