Directly Self-Assembling Method to Easily Prepare Rough Silk Fibroin Film

The surface roughness of silk fibroin biomaterials affects the adhesion and growth of cells on their surface. Silk fibroin molecules exhibit the natural ability to self-assemble. By utilizing this feature, a silk fibroin film with rough surfaces can be easily prepared. Scanning electron microscopy and atomic force microscopy results showed micro-/nanoscale protrusions with a uniform distribution over the film surface. The film structure characterization and dynamic light scattering results confirmed that this is because the silk fibroin molecules self-assemble in solution to form relatively large aggregates. These aggregates penetrate the surface of the film during drying, thereby forming these tiny protrusions on the film surface. Furthermore, the results of the cell adhesion test prove that this rough surface is more conducive to cell adhesion and growth thereon.