Channel structure design and biological properties of silk fibroin/sericin sponge nerve scaffolds

Sponge materials with different ratios of silk fibroin and sericin and different channel structures were prepared as neural brackets to explore their physicochemical properties. The brackets were fabricated by cross-linking silk protein and sericin through glutaraldehyde and solution casting method, the aggregation state structure of the material was detected by fourier infrared, the morphology and structure of the material was observed by scanning electron microscope, and the physicochemical properties were detected by in vitro dissolution experiments, degradation experiments, and mechanical property experiments. The above analysis showed that the material is a porous mesh structure, and the pore size decreases with the increase of sericin content, while the swelling rate increases with the increase of channel area, the degradation rate increases, and the mechanical properties decrease. The proportion of 1:0.5 shows the best physicochemical performance in terms of the ratio of silk fibroin to sericin, The cytotoxicity and animal experiments indicated that this material has no cytotoxicity, and could promote cell proliferation and differentiation, the different types of brackets suggest promotion effects on nerve regeneration. In this paper, three kinds of nerve brackets, including porous structure, 24-channel structure and 4-channel structure, were designed to explore which structure is more conducive to nerve regeneration and lays a foundation for the design of biomimetics nerve scaffolds in the future, and it is expected to play a role in various peripheral nerve injuries. In the present study, a 4-channel nerve scaffold with a fibroin/ sericin ratio of 1:0.5 showed the best effect in repairing a 10-mm sciatic nerve deficit in rats.