Fabrication of TiO₂ Nanoparticles with High Colloidal Stability through Surface Modification via Biocompatible Block...

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Titanium dioxide nanoparticles (TiO2 NPs) have valuable properties but limited biomedical use due to poor stability in physiological conditions.
• Surface modification is crucial to enhance nanoparticle stability for in vivo applications.

Purpose of the Study:

• To develop stable TiO2 nanoparticles for biomedical applications.
• To investigate the effect of polymer modification and heat treatment on TiO2 NP stability and sonosensitizer function.

Main Methods:

• Synthesis of poly(oligoethylene glycol methacrylate) (POEGMA) and POEGMA-block-poly(2-methacryloyl oxyethyl phosphoryl choline) (POEGMA-block-PMPC) polymers with phosphonic acid end groups.
• Anchoring polymers to TiO2 NP surfaces.
• Dynamic light scattering (DLS) to assess colloidal stability in phosphate-buffered saline (PBS).
• Evaluation of sonosensitizer efficacy after modification and heat treatment.

Main Results:

• Polymer modification significantly improved the colloidal stability of TiO2 NPs in PBS.
• Increasing polymer molecular weight enhanced stability.
• Post-modification heat treatment further improved stability, attributed to altered phosphonic acid-TiO2 coordination.
• The modified TiO2 NPs retained their sonosensitizer function after heating.

Conclusions:

• Phosphonic acid-terminated POEGMA and POEGMA-block-PMPC polymers effectively stabilize TiO2 NPs.
• Heat treatment enhances the stability of modified TiO2 NPs without compromising their sonosensitizer properties.
• These stabilized TiO2 NPs show promise for biomedical applications, particularly in sonodynamic therapy.