Superamphiphilic TiO₂ Composite Surface for Protein Antifouling

Area of Science:

• Materials Science
• Surface Chemistry
• Biomaterials Engineering

Background:

• Unwanted protein adsorption on surfaces causes device fouling and reduced performance in analytical and biomedical applications.
• Understanding protein-surface interactions and developing stable, protein-resistant coatings remain critical challenges.
• Wettability significantly influences protein adsorption dynamics, but comprehensive principles are still under investigation.

Purpose of the Study:

• To develop a nanostructured superamphiphilic coating to prevent nonspecific protein adsorption.
• To investigate the mechanism by which superamphiphilicity inhibits protein adhesion.
• To demonstrate the coating's utility in capillary electrophoresis and microfluidic devices.

Main Methods:

• Fabrication of a nanostructured titanium dioxide/silicon dioxide (TiO2/SiO2) composite coating.
• Characterization of the coating's superamphiphilic properties and surface energy.
• Evaluation of protein adsorption resistance using model proteins in aqueous environments.
• Testing the coating's performance in capillary electrophoresis channels and microfluidic liquid transport.

Main Results:

• The TiO2/SiO2 composite coating exhibited superamphiphilic behavior, repelling both water and oils.
• A confined water layer on the superamphiphilic surface created a low adhesion force and an energy barrier, significantly reducing protein adsorption.
• The coating demonstrated long-term stability and effectively prevented fouling in capillary electrophoresis.
• Successful application in multifunctional microfluidics for controlled liquid transportation was achieved.

Conclusions:

• Nanostructured superamphiphilic TiO2/SiO2 coatings offer a robust solution for preventing protein adsorption.
• The underlying mechanism involves a confined water layer that creates an energy barrier to protein adhesion.
• This facile approach has broad implications for designing advanced superwetting materials for biomedical devices, microfluidics, and bioassays.