Fabrication Of 3D Scaffold With Inverse Opal Structure Based On Silk Fibroin

Silk is an ancient material which has been utilized by human for thousands of years. Silk fibroin (SF) is a nature protein obtained from the Bombyx mori. SF is constituted of 18 kinds of amino acid especially the polypeptide -Gly-Ala-Gly-Ala-Ser-. SF has been used as the material of surgical sutures for hundreds of years. The excellent mechanical and optical properties as well as its biocompatibility and biodegradability make SF a great prospective material within high-technology material platform in biomedical application.In treating tissue damage, tissue engineering is able to void many problems caused by a traditional method, such as immune rejection and donor shortage. Among various topics related to tissue engineering, the structures and properties of the scaffolds have been studied extensively in the context of material science and biomedical engineering. The structure of scaffold should be available for the transformation of nutrient and metabolite for cell culture. SF is a biomaterial with excellent biocompatibility and biodegradability. We hope to apply SF in cell scaffold and construct an inverse opal structure 3D scaffold.In this paper, we propose a convenient method to fabricate an inverse opal structure scaffold based on silk fibroin. The main contents are as follows.1. Extraction and gelation of Silk fibroin:we extracted SF from Bombyx mori and evaluated the feature of different extracting system. SF was transferred to types of forms, like hydrogel, sponge, nano-fibers. Different properties of SF forms were considered for the later experiment.2. Construction of 3D scaffold with inverse opal structure:three materials of monodisperse template microspheres were fabricated by microfluidic device. Polycaprolactone (PCL) microspheres were evaluated the best material to form cubic-close packed structure. SF was infiltrated into the interspace of cubic-close packed lattice in order to duplicate the structure. Finally, the 3D SF scaffold with inverse opal structure is obtained by eliminating PCL microspheres.3. Cell culture in SF scaffolds:we investigated the differences between SF hydrogel scaffold and SF sponge scaffold through cell culture experiment. The excellent mechanical property makes SF sponge superior to form 3D scaffold with inverse opal structure.3D SF scaffold was characterized of the cell adhesion through inverted fluorescence microscope and biological activity by MTT method.