Silk is a naturally occurring biopolymer formed into fibers composed primarily of fibroin and sericin proteins. The outstanding mechanical properties of silk fibroin (SF) provides numerous applications for silk-based biomaterials. However, the canonical approaches for fabricating silk-based biomaterials typically involve degumming to remove the silk sericin (SS) to avoid adverse biological effects. Meanwhile, sericin has multiple biological functions including outstanding hydrophilicity, promoting cell attachment that are useful to exploit in new materials, inspiring the use of sericin-based biomaterials for biomedical applications. However, compared to fibroin, sericin is not a structural protein, thus sericin-based materials do not provide robust mechanical properties. To address this problem, we report an effective method for fabricating silk fibroin-sericin protein (SS-SF) composites directly from whole cocoons, negating the traditional extraction step to remove the sericin. This approach combines the material features from both fibroin as a structural unit and sericin as a biological functional unit, to achieve advantages regarding processing and materials properties, not only simplifying processing and maintaining the mechanical properties of the fibroin by avoiding degumming, but also endowing these SS-SF composite materials with enhanced hydrophilicity and cell adhesion performance to promote cell growth and proliferation. In addition, these protein composites could be fabricated into a variety of materials formats (e.g. films, sponges, monoliths) to fit different biomedical applications.

丝是一种天然存在的生物聚合物，形成纤维，主要由丝心蛋白和丝胶蛋白组成。丝素蛋白（SF）出色的机械性能为丝基生物材料提供了众多应用。然而，制造丝基生物材料的标准方法通常涉及脱胶以去除丝胶（SS），以避免不利的生物效应。同时，丝胶具有多种生物学功能，包括出色的亲水性、促进细胞附着，可用于新材料的开发，激发基于丝胶的生物材料在生物医学领域的应用。然而，与丝心蛋白相比，丝胶蛋白不是结构蛋白，因此基于丝胶蛋白的材料不能提供稳健的机械性能。为了解决这个问题，我们报告了一种直接从整个茧中制造丝素蛋白-丝胶蛋白（SS-SF）复合材料的有效方法，取消了去除丝胶的传统提取步骤。该方法结合了丝素作为结构单元和丝胶作为生物功能单元的材料特性，实现了加工和材料性能方面的优势，不仅简化了加工并通过避免脱胶保持了丝素的机械性能，而且还赋予了这些特性。 SS-SF复合材料具有增强的亲水性和细胞粘附性能，促进细胞生长和增殖。此外，这些蛋白质复合材料可以加工成各种材料形式（例如薄膜、海绵、整体材料）以适应不同的生物医学应用。