Composite PEG/silk fibroin scaffolds : a proof of concept

Three dimensional scaffolds made of silk fibroin (SF) from Bombix mori silkworm require a final curing to manipulate the protein secondary structure of SF (i.e. the ratio between the β-sheets and random-coil regions) in order to satisfy the requirements of tissue engineering. However, hydrodynamic environment potentially impacts the functional properties of these structures due to the decreased the pore dimension and limited oxygen and nutrient diffusion. This work aims to evaluate the feasibility of preparing composite PEG/SF scaffold with an enhanced water stability upon incubation in physiologic media over time. Low molecular weight PEG was chosen because the blending with SF induces the formation of β-sheet domains. Composite scaffolds loaded with a pool of growth factors and micronized hydroxyapatite were subcutaneously implanted in pigs to assess their in vivo performance...