1. Department of Biomedical Engineering, College of Engineering and Applied Sciences, Collaborative Innovation Center of Chemistry for Life Sciences, Nanjing National Laboratory of Microstructures, Nanjing University, Nanjing, Jiangsu, 210093, China;
2. Department of Urology, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu, 210008, China;
3. State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China;
4. State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Catalytic nanomaterials with intrinsic enzyme-like activities, called nanozymes, have recently attracted significant research interest due to their unique advantages relative to natural enzymes and conventional artificial enzymes. Among the nanozymes developed, particular interests have been devoted to nanozymes with peroxidase mimicking activities because of their promising applications in biosensing, bioimaging, biomedicine, etc. Till now, lots of functional nanomaterials have been used to mimic peroxidase. However, few studies have focused on the Ni-based nanomaterials for peroxidase mimics. In this work, we obtained the porous LaNiO3 nanocubes with high peroxidase-like activity by inducing its 3+ oxidation state in LaNiO3 perovskite and optimizing the morphology of LaNiO3 perovskite. The peroxidase mimicking activity of the porous LaNiO3 nanocubes with Ni3+ was about 58~fold and 22~fold higher than that of NiO with Ni2+ and Ni nanoparticles with Ni0. More, the porous LaNiO3 nanocubes exhibited about 2-fold higher activity when compared with LaNiO3 nanoparticles. Based on the superior peroxidase-like activity of porous LaNiO3 nanocubes, facile colorimetric assays for H2O2, glucose, and sarcosine detection were developed. Our present work not only demonstrates a useful strategy for modulating nanozymes' activities but also provides promising bioassays for clinical diagnostics.
Keywords: nanozymes, peroxidase-like activity, LaNiO3 perovskite oxide, oxidation state, biomedical assays.