Ultrasmall CeO_2-x@β-CD nanoparticles with pH-dependent prooxidant activity and doxorubicin loading/release capability

Area of Science:

• Nanotechnology
• Materials Science
• Biomedical Engineering

Background:

• Developing multifunctional nanoparticles for targeted cancer therapy is crucial.
• Cerium oxide nanoparticles (CeO_2-x NPs) exhibit promising catalytic and biomedical properties.
• Beta-cyclodextrin (β-CD) can be used for drug encapsulation and controlled release.

Purpose of the Study:

• To develop ultrasmall (2-3 nm) CeO_2-x@β-CD nanoparticles as combined nanozymes and drug delivery platforms.
• To investigate the nanozymatic activities (peroxidase-like, oxidase-like, thiol-oxidizing) of the synthesized nanoparticles.
• To evaluate the pH-dependent drug release profile of anticancer drug doxorubicin (DOX) from the nanoparticles for targeted cancer treatment.

Main Methods:

• Synthesis of multifunctional ultrasmall CeO_2-x@β-CD nanoparticles.
• Characterization of nanoparticle properties, including size and catalytic activity.
• Assay of peroxidase-like and oxidase-like activities using 3,3',5,5'-tetramethylbenzidine (TMB).
• Evaluation of pH-dependent doxorubicin (DOX) release kinetics.

Main Results:

• CeO_2-x@β-CD NPs demonstrated significant peroxidase-like and oxidase-like activities.
• Thiol-oxidizing ability was observed in the synthesized nanoparticles.
• Both nanozyme activity and DOX release were pH-dependent, enhanced in acidic conditions.
• Chemisorption of DOX within β-CD cavities ensured steady, long-lasting drug release.

Conclusions:

• Ultrasmall CeO_2-x@β-CD NPs show multifunctional capabilities as nanozymes and drug delivery systems.
• The pH-dependent properties enable selective targeting of acidic tumor microenvironments.
• These nanoparticles hold potential for developing advanced, long-term cancer treatment strategies.