Nanozymes with intrinsic enzyme-like properties and excellent stability are promising alternatives to natural enzymes. Yet, their low density of active sites and unclear crystal structure have been the major obstacles that impede their progress. Single-atom nanozymes (SAzymes) have emerged as a unique system to mitigate these issues, due to maximal atomic utilization, well-defined electronic and geometric structures, and outstanding catalytic activity distinct from their nanosized counterparts. Furthermore, the homogeneously dispersed active sites and well-defined coordination structures provide rare pathways to shed light on the catalytic mechanisms. In this review, we summarize the latest progress in the rational design and engineering of SAzymes and their applications in biomedicine and biosensing. We then conclude the review with highlights of the remaining challenges and perspectives of this emerging technology.
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Nanozymes—Hitting the Biosensing “Target”
Nanozymes are a class of artificial enzymes that have dimensions in the nanometer range and can be composed of simple metal and metal oxide nanoparticles, metal nanoclusters, dots (both quantum and carbon), nanotubes, nanowires, or multiple metal-organic frameworks (MOFs). They exhibit excellent catalytic activities with low cost, high operational robustness, and a stable shelf-life. More importantly, they are amenable to modifications that can change their surface structures and increase the range of their applications. There are three main classes of nanozymes including the peroxidase-like, the oxidase-like, and the antioxidant nanozymes. Each of these classes catalyzes a specific group of reactions. With the development of nanoscience and nanotechnology, the variety of applications for nanozymes in diverse fields has expanded dramatically, with the most popular applications in biosensing. Nanozyme-based novel biosensors have been designed to detect ions, small molecules, nucleic acids, proteins, and cancer cells. The current review focuses on the catalytic mechanism of nanozymes, their application in biosensing, and the identification of future directions for the field.
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- Award ID(s):
- 1946202
- NSF-PAR ID:
- 10318360
- Date Published:
- Journal Name:
- Sensors
- Volume:
- 21
- Issue:
- 15
- ISSN:
- 1424-8220
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/s21155201
