Nanozymes With POD-like Activity

Introduction

So far, many nanozymes with peroxidase (POD)-like activity have been discovered. They have strong environmental adaptability and antioxidant capacity, and can catalyze the decomposition of H₂O₂ to protect cells from oxidative damage, thereby helping to maintain the stability and safety of organisms to a certain extent. In addition, they can be used for biosensing and combating bacteria. Due to the excellent performance and catalytic activity of nanozymes with POD-like activity, researchers will continue to explore their wider applications.

Study On Catalytic Mechanism

In view of the broad development prospects of nanozymes with POD-like activity, researchers have begun to gain an in-depth understanding of their possible catalytic mechanism, which will help develop new and efficient nanozymes with POD-like activity and broaden their application fields. Recently, numerous carbon-based nanozymes have been found to exhibit excellent POD-like properties, and their catalytic mechanisms have been gradually explored. For example, Qu et al. took graphene quantum dots (GQDs) as the example to explore the catalytic mechanism. Combined with experimental data as well as theoretical calculation, they found that the −C=O and O=C−O− groups could serve as the catalytic activity sites and substrate-binding sites, respectively. The modification of these groups might effectively improve the catalytic activity of GQDs. On the contrary, the presence of the −C−OH groups would inhibit their catalytic property^[1]. Besides, since the discovery that Fe₃O₄ nanoparticles can serve as POD mimics, their catalytic mechanism has also begun to be explored. By combining electron spin resonance (ESR) measurements with a radical inhibition assay, the possible catalytic mechanism of Fe₃O₄ magnetic nanoparticles as POD mimics was proposed by Tang et al. H₂O₂ molecules are adsorbed on the surface of Fe₃O₄ magnetic nanoparticles and then activated by the bound Fe²⁺ and Fe³⁺ to generate ·OH and O₂-·/HO₂· radicals. Although both ·OH and O₂^-·/HO₂· radicals are formed in the Fe₃O₄-involved catalytic reaction, the O₂^-·/HO₂· radicals dominate over the ·OH radicals as confirmed by the ESR measurements and the effect of radical inhibitors^[2].

Applications

Nanozymes with POD-like activity have been developed for biosensing and combating bacteria.

• Biosensing. In the field of biosensing, nanozymes with POD-like activity can be used in the detection of H₂O₂, glucose, protein and reduced glutathione. They can also be used to measure the antioxidant levels of small biomolecules (e.g. amino acids, trolox) and cells (e.g. human umbilical vein endothelial cells, senescent human umbilical vein endothelial cells, and Hela cells). Furthermore, highly selective nanozymes with POD-like activity can also be used for sensing in complicated biological samples such as cell lysate.

• Combating bacteria. Nanozymes with POD-like activity have antibacterial activity and can combat Gram-negative bacteria and positive bacteria such as Methicillinresistant Staphylococcus aureus (MRSA) and Escherichia coli. On the one hand, they can catalyze H₂O₂ to produce more toxic reactive oxygen species, such as ·OH, for antibacterial purposes. On the other hand, some nanozymes with POD-like activity can also release a small amount of metal ions to interfere with bacterial metabolism or enhance bacterial autophagy, thereby killing bacteria. In addition, nanozymes can also cooperate with photothermal therapy, sonodynamic therapy, etc. to jointly fight bacterial infections.

Alfa Chemistry offers a series of nanozymes with POD-like activity, which can be used for biosensing and combating bacteria. You can click on our product list for a detailed view. At the same time, we also offer product customization according to customer's detailed requirements. If you are interested in our products or have any questions or needs, please feel free to contact us. We will be happy to provide you with support and services.

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