LAUSR

The artificial nanozymes have been designed to solve the problems of high cost and poor stability involving of natural enzymes in analytical applications. Nevertheless, the catalytic efficiency of nanozyme still needed to be improved, so that it could meet the stability and sensitivity requirements in continuous biological detection. We presented an effective tailoring strategy to enhance the enzyme-like activities of Prussian blue analog-based nanozymes. A molybdenum polysulfide deposited nickel-iron bimetal Prussian blue analog-based hollow nanocages (Nanocages) with peroxidase, catalase and laccase mimicking activity was synthesized. The doping of molybdenum successfully tailored the size, morphology, composition as well as complex structure of Nanocage and the peroxidase and laccase mimicking activity of Nanocage nanozyme were enhanced by over 37-fold and 27-fold, respectively, compared with pristine Prussian blue analogs. Moreover, in the environments of harsh pH, high temperature and high salt concentrations, Nanocages exhibited much higher stability than natural enzymes. The peroxidase and catalase mimicking activity were applied for reactive oxygen species eliminating in cells while the laccase-like activity of Nanocages was integrated with online sensing platform for in vivo and continuous optical hydrogen sulfide monitoring in brains of living rats. Our findings may provide possibilities in advancing the design strategy for highly active nanozymes as well as nanozyme-based in vivo detection methods, and will offer unique opportunities involved in bioanalytical chemistry.