Abstract

We attempted to produce three dimensional (3D) aero-sponges using liquid silk (LS) extracted from the silk glands of fully grown larvae of Bombyx mori silkworms by combining an ice-crystal-sublimation method and a water-annealing treatment. The pore structure of the 3D LS-aero-sponge was constructed by the branched fibrous substrates and the films with small holes. It was assumed that the branched fibrous structure was mainly comprised of fibroin whereas the films were comprised of the fibroin interacting with the sericin fractions. Most of the WAXD peaks from the as-molded 3D LS-aero-sponge could be assigned to the silk1 crystal diffraction peaks of fibroin. The silk1 crystal modification of fibroin formed in the course of the production of the 3D LS-aero-sponge could bring about a good thermal shrinkproof property. Furthermore, a gamma ray irradiation treatment applied prior to the cell proliferation tests of the 3D LS-aero-sponges was found to be effective to form cross-linking in the sericin fractions. As a result, the yield stress in the compression tests of the 3D LS-aero-sponges was increased. The 3D LS-aero-sponge exhibited a good living cell proliferation properly in the culture tests using NH3T3 cells (Swiss albino mice embryonic fibroblasts) although that of the 2D LS-cast films was very poor. We suggest the good cell proliferation property of the 3D LS-aero-sponge was due to the continuous branched fibrous structure comprised of fibroin.

摘要

我们尝试使用从完全生长的家蚕幼虫的丝腺中提取的液体丝 (LS) 生产三维 (3D) 航空海绵蚕采用冰晶升华法和水退火处理相结合。3D LS-气动海绵的孔结构由支化的纤维基材和带有小孔的薄膜构成。假设分支纤维结构主要由丝心蛋白组成，而膜由与丝胶组分相互作用的丝心蛋白组成。来自模制 3D LS-aero-sponge 的大多数 WAXD 峰可归属于丝心蛋白的 Silk1 晶体衍射峰。在3D LS-航空海绵生产过程中形成的丝心蛋白的silk1晶体修饰可以带来良好的热收缩性能。此外，发现在 3D LS-aero-sponges 的细胞增殖测试之前应用的伽马射线辐照处理可有效地在丝胶组分中形成交联。结果，增加了 3D LS-航空海绵压缩试验中的屈服应力。3D LS-aero-sponge 在使用 NH3T3 细胞（瑞士白化小鼠胚胎成纤维细胞）的培养试验中表现出良好的活细胞增殖，尽管 2D LS-cast 薄膜的增殖非常差。我们认为 3D LS-aero-sponge 的良好细胞增殖特性是由于由丝心蛋白组成的连续分支纤维结构。3D LS-aero-sponge 在使用 NH3T3 细胞（瑞士白化小鼠胚胎成纤维细胞）的培养试验中表现出良好的活细胞增殖，尽管 2D LS-cast 薄膜的增殖非常差。我们认为 3D LS-aero-sponge 的良好细胞增殖特性是由于由丝心蛋白组成的连续分支纤维结构。3D LS-aero-sponge 在使用 NH3T3 细胞（瑞士白化小鼠胚胎成纤维细胞）的培养试验中表现出良好的活细胞增殖，尽管 2D LS-cast 薄膜的增殖非常差。我们认为 3D LS-aero-sponge 的良好细胞增殖特性是由于由丝心蛋白组成的连续分支纤维结构。