Biological activity of cerium dioxide nanoparticles

Area of Science:

• Nanotechnology
• Biochemistry
• Materials Science

Background:

• Cerium dioxide nanoparticles (CeO₂ NPs) can form stable aqueous suspensions without stabilizers due to high ζ-potential.
• Interactions between nanoparticles and biological molecules like proteins are crucial for understanding nanoparticle behavior in biological systems.

Purpose of the Study:

• To investigate the interaction of stable CeO₂ NPs with bovine serum albumin (BSA).
• To evaluate the antioxidant activity and toxicity of CeO₂ NPs.

Main Methods:

• Synthesis of CeO₂ NPs in reverse microemulsions.
• Spectroscopic analysis (UV-absorbance, fluorescence quenching) to study BSA conformation changes.
• Differential scanning calorimetry (DSC) to assess BSA-CeO₂ NP affinity.
• Assessment of free-radical scavenging activity and cytotoxicity assays on MT-4 and MCF-7 cells.

Main Results:

• CeO₂ NPs induced structural changes in BSA, affecting its biochemical activity.
• Low affinity between BSA and CeO₂ NPs was confirmed by DSC.
• CeO₂ NPs demonstrated concentration-dependent antioxidant activity as free-radical scavengers.
• Positively charged CeO₂ NPs exhibited low toxicity toward MT-4 and MCF-7 cells.
• Interaction with MCF-7 cells indicated a decrease in oncogenicity.

Conclusions:

• Stable, positively charged CeO₂ NPs interact with proteins, altering their structure and activity.
• CeO₂ NPs possess significant antioxidant properties and low cytotoxicity.
• These findings suggest potential applications for CeO₂ NPs in biomedical fields, including cancer therapy, due to reduced oncogenicity.