1 research outputs found
Biofunctionalization of Titanium Substrates Using Nanoscale Polymer Brushes with Cell Adhesion Peptides
The grafting of polymer brushes to substrates is a promising method
to modify surface properties such as wettability and the affinity
toward proteins and cells for applications in microelectronics, biomedical
devices, and sensors. PolyÂ(acrylic) acid (PAA) brushes are of high
interest because of their stimuli-responsive behavior and the presence
of carboxy (COOH) groups, which allow for immobilization of bioactive
molecules. The “grafting-to” approach results in homogeneous
and well-defined polymer brushes, but, although grafting-to has been
demonstrated with PAA brushes on silicon (Si) substrates, it has not
been performed on biocompatible materials such as titanium (Ti). Here,
we have described a facile method to modify biocompatible Ti substrates
with PAA brushes to amplify their substrate functionality. The grafting-to
PAA “pseudo” brushes were successfully grafted to Ti
substrates and retained their pH-dependent swelling behavior. An RGD
peptide was covalently bound to COOH groups of the PAA brushes (PAA–RGD)
as a model bioactive group. While NIH/3T<sub>3</sub> cell adhesion
was significantly decreased on PAA-functionalized Ti substrates, PAA–RGD
on Ti had cell adhesion comparable to that of flat Ti at 24 and 48
h, with significantly more cells adhered to PAA–RGD compared
to PAA on Ti at 48 h