Biomedical Applications of Nanozymes: An Enzymology Perspective

Nanozymes are catalytic nanomaterials that transform enzyme substrates into their corresponding products, offering enhanced stability and a cost-effective alternative to traditional enzymes. As nanomaterials, they possess unique physicochemical properties and catalytic mechanisms distinct from those of enzymes. Such differences have profound, yet often neglected, implications in biomedical applications. In the context of enzymology, this review compares nanozymes and enzymes, with a focus on redox reactions. This review begins with the classification of nanozymes based on the types of reactions they catalyze, with the ability to exhibit multiple catalytic activities being a prevalent characteristic. The use of the Michaelis-Menten model for both enzymes and nanozymes is discussed in detail, and the Michaelis constant, maximum reaction rate, and turnover number values are compared. The performance of nanozymes in crowded environments and under extreme conditions is also compared to that of enzymes. We discuss the kinetic factors influencing nanozyme performance, the impact of active site shielding, and the activity under non-physiological conditions. We then compiled recent trends in the biomedical applications of nanozymes, focusing on both the production and scavenging of reactive oxygen species. This review links fundamental enzymology to nanozyme catalysis, providing a key reference for the rational use of nanozymes.