Collagen release kinetics of surface functionalized 45S5 Bioglass-based porous scaffolds

A highly interconnected porous scaffold made from 45S5 Bioglass was fabricated by the polymer replica technique and surface functionalized for protein immobilization. Subsequently rat-tail collagen type I was immobilized on the scaffolds. The protein and ion release rates were determined by UV-vis spectroscopy and ion chromatography, respectively, and the impact on hydroxyapatite (HA) formation on the scaffolds upon immersion in SBF was evaluated. It was discovered that the surface functionalization enhanced the stability of the collagen attachment and stability against the increment of pH in a biological environment, resulting in similar collagen release kinetics in solutions of different pH values. Without the surface modification, collagen release was considerably expedited by the increment of pH in a surrounding solution. It was also found that the collagen immobilization does not effect the formation of carbonated HA on the scaffold surface. The stable collagen attachment to the functionalized scaffold makes this approach potentially suitable for improving cell attachment and thus for enhancing the application potential of the scaffold in tissue engineering.