Movable Polyrotaxane Surfaces for Modulating Cellular Adhesion via Specific RGD-Integrin Binding

Abstract

Immobilizing bioactive molecules on the materials surfaces is one of the main strategies for creating functional bio-interfaces. In these kinds of bio-interfaces, the density of immobilized functional groups and the following physicochemical factors such as roughness, polarity and electrical charge have been thought important variables for regulating biological responses such as cell adhesion and differentiations. Here in this study, differences between rigidity and dynamically immobilized bioactive molecules on the biological responses will be discussed. In order to develop dynamic bio-interfaces, a polyrotaxane based block-copolymer containing clickable azide groups for conjugating various bioactive molecules was designed. Cell adhesive RGD peptide was then conjugated with the azide group by click reaction on both dynamic and rigid surfaces. As a result, cell adhesive RGD peptide immobilized on the dynamic bio-interfaces shows larger initial cell adhesion area, indicating that molecular dynamics of surface chemical groups is another important variable for the regulation of biological responses.