Highly porous gelatin-silica hybrid scaffolds with textured surfaces using new direct foaming/freezing technique

Abstract

Highly porous gelatin silica hybrid scaffolds with high porosity, large pores and large interconnections, as well as tailored surface textures were produced using a newly developed direct foaming/freezing. Two different types of precursors as the silica source, 3-glycidoxyproyltrimethoxysilane (denoted as "GS") and sal gel derived silica (denoted as "SS"), were used for producing the porous GLA GS and GLA GS SS hybrid scaffolds. In this method, air bubbles could be vigorously incorporated into the GLA GS and GLA GS SS mixtures and then stabilized by rapid freezing of the foamed mixtures at 70 C. Both the porous GLA GS and GLA GS SS hybrid scaffolds produced herein had a highly porous structure (porosity > 90 vol%, pore size = 200-500 gm, interconnection size = 100-200 gm) with a uniform distribution of the silica phase in the gelatin matrix. In addition, surface textures with a rugged morphology could be created after immersion of the porous GLA GS and GLA GS SS hybrid scaffolds in ethanol at 20 C for 24 h. The porous GLA GS and GLA GS SS hybrid scaffolds showed much higher mechanical properties than the porous GLA scaffold, while preserving excellent in vitro biocompatibility, demonstrating potential application as the bone scaffold. (C) 2014 Elsevier B.V. All rights reserved.