Single-Atom Catalysts Boost Peroxidase-like Activity for Biosensing

Abstract

Natural enzymes are one of the most important compounds in biosensing applications. However, their wide application is limited by expensive production costs and instability in complex conditions like high temperature or harsh pH environments. It is urgent to develop artificial alternatives with enzyme-like properties and activity for natural enzymes with high stability and low-cost biomedical applications. We designed various single-atom catalysts (SACs) with a high peroxidase-like activity that was able to work as efficiently as natural enzymes. Herein, single iron atoms embedded in nitrogen-doped carbon nanomaterials (with Fe-Nx active site),1 which mimic the active site of heme enzymes from an atomic/molecular structure perspective. The SACs are also more robust than natural enzymes, which show excellent stability under pH or temperature changes. The superior catalytic specificity of hydrogen peroxide paved the way for replacing natural peroxidase for high-sensitive biosensing. For investigating practical applying ability, electrochemical sensors, immunosorbent assays, intercellular nanoprobe, and lateral-flow immunoassay based on SACs were successfully developed for biosensing and bioimaging applications.2-4 Their unique electronic/geometrical have significant advantages in biocatalytic activity, stability, and selectivity, which offer massive potential in substituting natural enzymes for various biomedical applications.5 Reference Ding, S.; Lyu, Z.; Zhong, H.; Liu, D.; Sarnello, E.; Fang, L.; Xu, M.; Engelhard, M. H.; Tian, H.; Li, T.; Pan, X.; Beckman, S. P.; Feng, S.; Du, D.; Li, J.-C.; Shao, M.; Lin, Y., An Ion-Imprinting Derived Strategy to Synthesize Single-Atom Iron Electrocatalysts for Oxygen Reduction. Small 2021, 17 (16), 2004454.Ding, S.; Lyu, Z.; Fang, L.; Li, T.; Zhu, W.; Li, S.; Li, X.; Li, J.-C.; Du, D.; Lin, Y., Single-Atomic Site Catalyst with Heme Enzymes-Like Active Sites for Electrochemical Sensing of Hydrogen Peroxide. Small 2021, 17 (25), 2100664.Lyu, Z.; Ding, S.; Wang, M.; Pan, X.; Feng, Z.; Tian, H.; Zhu, C.; Du, D.; Lin, Y., Iron-Imprinted Single-Atomic Site Catalyst-Based Nanoprobe for Detection of Hydrogen Peroxide in Living Cells. Nano-Micro Letters 2021, 13 (1), 146.Lyu, Z.; Ding, S.; Zhang, N.; Zhou, Y.; Cheng, N.; Wang, M.; Xu, M.; Feng, Z.; Niu, X.; Cheng, Y.; Zhang, C.; Du, D.; Lin, Y., Single-Atom Nanozymes Linked Immunosorbent Assay for Sensitive Detection of A<i>β</i> 1-40: A Biomarker of Alzheimer’s Disease. Research 2020, 2020, 4724505.Jiao, L.; Xu, W.; Wu, Y.; Yan, H.; Gu, W.; Du, D.; Lin, Y.; Zhu, C., Single-atom catalysts boost signal amplification for biosensing. Chemical Society Reviews 2021, 50 (2), 750-765. Figure 1