Peroxidase-like activity of photochromic PVP-stabilized tungsten oxide nanoparticles: assessment by independent chemiluminescent and colorimetric assays

In this work, peroxidase-like activity of ultrasmall tungsten oxide nanoparticles including those stabilized with polyvinylpyrrolidone (PVP) was assessed using two independent approaches: the colorimetric method, which is based on the analysis of 3,3’,5,5’-tetramethylbenzidine (TMB) oxidation, and the luminolenhanced chemiluminescence method. It was demonstrated that bare tungsten oxide nanoparticles effectively catalyze the decomposition of hydrogen peroxide. In turn, the PVP-stabilized nanoparticles possess lower catalytic activity, which can be attributed to a decrease in the number of available active centres on the nanoparticle surface.