Surface ligand-regulated nanointerfaces: Enhancing the catalytic activity and selectivity of platinum nanozymes for biomedical applications
Yuanyuan Li, Zihang Zeng, Jiajun Tong, Tao Yang, Gonghao Liu, Bo Feng, Peng Zhang, Xiaofeng Liu, Taiping Qing
Abstract
Platinum nanoparticles (Pt NPs) have aroused tremendous attention due to the significant enzyme-like activity, controllable synthesis and biosafety. However, it remains a challenge to properly design the morphology and surface properties of Pt NPs to obtain the desired enzyme-like activity and substrate selectivity. Herein, a surface engineering strategy is employed to adjust the catalytic performance of Pt NPs by modifying different functional groups, thereby promoting its oxidase-like activity and catalytic specificity to substrate. The catalytic performance of Pt NPs with various thiolate ligands was evaluated using TMB, ABTS and OPD as substrates. The k cat / K m values revealed that Pt NPs modified by 6-mercapto-6-deoxybeta-cyclodextrin (Pt@CD) had a strong substrate selectivity for TMB, but a weak selectivity for ABTS and OPD, with a catalytic specificity to TMB nearly 3.4 times that of bare Pt NPs. When uric acid was used as substrate, PtNP_32 showed better environmental stability and uric acid degradation efficiency than uricase. More importantly, the PtNP_32 did not cause hemolysis and had good biocompatibility, making it a promising candidate for the treatment of hyperuricemia-related diseases. This work provides a new strategy to improve the catalytic performance of platinum nanozymes for efficient and selective degradation of uric acid.