Biofunctionalization of Titanium Substrates Using Nanoscale Polymer Brushes with Cell Adhesion Peptides

Area of Science:

• Materials Science
• Biomaterials Engineering
• Surface Chemistry

Background:

• Polymer brushes modify surface properties for applications in electronics, biomedical devices, and sensors.
• Poly(acrylic) acid) (PAA) brushes offer stimuli-responsive behavior and functional groups for biomolecule immobilization.
• The 'grafting-to' method yields well-defined polymer brushes, but its application on biocompatible titanium (Ti) substrates is underexplored.

Purpose of the Study:

• To develop a facile method for grafting PAA brushes onto biocompatible Ti substrates.
• To investigate the functionality and cell interaction of PAA-modified Ti surfaces.
• To enhance Ti substrate functionality for biomedical applications.

Main Methods:

• Grafting-to approach to synthesize PAA brushes on Ti substrates.
• Characterization of PAA brush grafting and pH-dependent swelling behavior.
• Covalent immobilization of RGD peptides onto PAA brushes (PAA-RGD) for cell adhesion studies.

Main Results:

• Successful grafting of PAA brushes onto Ti substrates was achieved, retaining pH-dependent swelling.
• PAA brushes on Ti significantly reduced NIH/3T3 cell adhesion.
• PAA-RGD functionalized Ti surfaces showed cell adhesion comparable to bare Ti and significantly enhanced adhesion compared to PAA-Ti at 48 hours.

Conclusions:

• A facile method to graft PAA brushes onto Ti substrates was established, enhancing substrate functionality.
• PAA-RGD functionalization of Ti surfaces promotes cell adhesion, indicating potential for biomedical applications.
• Stimuli-responsive PAA brushes on Ti offer a versatile platform for tailoring surface properties and biological interactions.