Photothermal-enhanced tandem enzyme-like activity of Ag2-xCuxS nanoparticles for one-step colorimetric glucose detection in unprocessed human urine

It is greatly significant and difficult to realize the purpose of natural enzyme free and “one-step” for traditional colorimetric urine glucose detection. Here, ultra-small Ag2-xCuxS nanoparticles (NPs) with tandem enzyme-like activity, i.e. they simultaneously exhibit glucose oxidase (GOx)- and peroxidase-like activities, are developed for tandem glucose oxidation and colorimetric H2O2 detection. Cu doping content has a great influence on the enzyme-like activity. Ag1.8Cu0.2S NPs (i.e. Ag2-xCuxS NPs with 10 % Cu) exhibit the best catalytic performance. The tandem enzyme-like activity can be further enhanced to ∼10 times under laser irradiation due to photothermal effect. Furthermore, accurate glucose detection has been realized in unprocessed human urine based on the photothermal-enhanced tandem enzyme-like activity of Ag1.8Cu0.2S NPs. This natural enzyme free and “one-step” colorimetric glucose detection strategy exhibits the potential application of the new generation of tandem enzyme-like nanomaterials.