Stabilized and Controlled Release of Radicals within Copper Formate-Based Nanozymes for Biosensing

Authors：Zhou, Yue; Chen, Xiaohua; Zhan, Shaoqi^*; Wang, Qiang; Deng, Feng; Wu, Qingzhi; Peng, Jian^*

Source：ACS applied materials & interfaces, 2023, 15(37): 43431-43440.

DOI：10.1021/acsami.3c08326

• Cuf-TMB nanozymes
• (OH)-O-. radicals
• peroxidase-likeactivity
• radical stability
• biosensors

Fenton-like radical processes are widely utilized to explain catalytic mechanisms of peroxidase-like nanozymes, which exhibit remarkable catalytic activity, cost-effectiveness, and stability. However, there is still a need for a comprehensive understanding of the formation, stabilization, and transformation of such radicals. Herein, a copper formate-based nanozyme (Cuf-TMB) was fabricated via a pre-catalytic strategy under ambient conditions. The as-prepared nanozyme shows comparable catalytic activity (K-m, 1.02 x 10(-5) mM(-1); K-cat, 3.09 x 10(-2) s(-1)) and kinetics to those of natural peroxidase toward H2O2 decomposition. This is attributed to the feasible oxidation by *OH species via the *O intermediate, as indicated by density functional theory calculations. The key .OH radicals were detected to be stable for over 52 days and can be released in a controlled manner during the catalytic process via in situ electron spin-resonance spectroscopy measurements. Based on the understanding, an ultrasensitive biosensing platform was constructed for the sensitive monitoring of biochemical indicators in clinic settings.

• Institution
  武汉理工大学; 南方医科大学; 中国科学院