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Catalytic Scavenging of Plant Reactive Oxygen Species In Vivo by Anionic Cerium Oxide Nanoparticles
Published on: August 26, 2018
Nanoceria exhibit redox state-dependent catalase mimetic activity
Talib Pirmohamed1, Janet M Dowding, Sanjay Singh
1Burnett School of Biomedical Science, 4000 Central Florida Blvd., Bldg. 20 Room 124, Orlando, Florida, USA.
Chemical Communications (Cambridge, England)
|April 7, 2010
Summary
Cerium oxide nanoparticles show catalase-like activity. This activity is linked to lower levels of cerium in the +3 oxidation state, differing from other nanoparticle properties.
Area of Science:
- Nanotechnology
- Biochemistry
- Materials Science
Background:
- Cerium oxide nanoparticles (nanoceria) are investigated for their antioxidant properties.
- Understanding the redox state of cerium is crucial for nanoceria's biological activity.
Purpose of the Study:
- To investigate the catalase mimetic activity of cerium oxide nanoparticles.
- To correlate this activity with the oxidation state of cerium on the nanoparticle surface.
Main Methods:
- Synthesis and characterization of cerium oxide nanoparticles.
- Assay of catalase mimetic activity.
- X-ray photoelectron spectroscopy (XPS) to determine cerium oxidation states.
Main Results:
- Cerium oxide nanoparticles demonstrated significant catalase mimetic activity.
- Catalase mimetic activity was inversely correlated with the +3 cerium ion concentration.
- This contrasts with the known positive correlation between surface charge and superoxide scavenging activity.
Conclusions:
- The findings reveal a novel relationship between cerium oxidation state and catalase mimetic activity in nanoceria.
- This suggests distinct mechanisms for different antioxidant activities of cerium oxide nanoparticles.
- Further research is needed to elucidate the precise mechanisms involved.
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