Development of Gelatin-Thai Silk Fibroin Microspheres for Three Dimensional Cell Culture

Microspheres have been widely used for tissue engineering scaffolds. Microspheres have many advantages over the macrostructure such as high surface area for cell adhesion and proliferation and low mass transfer limits. In this study, we fabricated microspheres from gelatin and silk fibroin using water-in-oil (w/o) emulsion technique and glutaraldehyde crosslinking. Gelatin (G) and silk fibroin (SF) were blended at different G/SF weight blending ratios of 100/0, 90/10, 70/30, and 50/50. Physical and chemical properties of the microspheres including size and morphology were characterized. The Average size of microspheres obtained were at 858.42±41.93, 832.97± 9.44 , 785.24±17.66 and 735.83 ±13.19 μm, respectively. Morphology of G/SF microspheres was observed under a scanning electron microscope. Blending of silk fibroin increased the crosslinking degrees and water absorption. It also reduced degradation rate, comparing to the gelatin microspheres. Thein vitroattachment and proliferation of rat bone marrow derived mesenchymal stem cells (MSC) cultured on G/SF microspheres were evaluated. G/SF 50/50 microspheres promoted the highest attachment of MSC on microspheres (46.0±5.8% of initial seeding at 6 hr). The G/SF 70/30 microspheres promoted the higher cell proliferation of MSC compared the others. Specific growth rate of the cells on the microspheres was at 9.85x10-3h-1.