Prussian Blue and Other Metal–Organic Framework-based Nanozymes

Metal–organic frameworks (MOFs) is a class of crystalline solid materials, whose well-defined pore structure makes them good candidates for the mimicking of natural enzymes. On one hand, MOFs are suitable for enzyme immobilization due to their porosity and multiplex structures. On the other hand, transition metal nodes containing MOFs themselves can play as biomimetic catalysts. Typically, Prussian blue (PB) is meaningful and influencing for developing MOF. Not strictly, PB is the first MOF structure that has been used for electrode modification owing to their good redox activity and high electrochemical stability. These characteristics also endow PB the potential to become an “artificial enzyme”. In this chapter, the use of MOFs and Prussian blue nanoparticles (PBNPs) for mimicking natural enzymes is discussed. History, structure, and properties of MOFs and PB are elaborated. The peroxidase, catalase, superoxide dismutase, and ascorbic acid oxidase-like activities of PBNPs are summarized. The catalytic mechanisms are also discussed. Selected examples for in vitro biodetection, in vivo bioimaging, and therapeutics are covered to highlight the broad applications of MOFs and PBNPs based on their multienzyme-like activities.