Due to its excellent biological and mechanical properties, silk fibroin has been intensively explored for tissue engineering and regenerative medicine applications. However, lack of translational evidence has hampered its clinical application for tissue repair. Here a silk fibroin film is developed and its translational potential is investigated for skin repair by performing comprehensive preclinical and clinical studies to fully evaluate its safety and effectiveness. The silk fibroin film fabricated using all green chemistry approaches demonstrates remarkable characteristics, including transmittance, fluid handling capacity, moisture vapor permeability, waterproofness, bacterial barrier properties, and biocompatibility. In vivo rabbit full-thickness skin defect study shows that the silk fibroin film effectively reduces the average wound healing time with better skin regeneration compared with the commercial wound dressings. Subsequent assessment in porcine model confirms its long-term safety and effectiveness for full-thickness skin defects. Finally, a randomized single-blind parallel controlled clinical trial with 71 patients shows that the silk fibroin film significantly reduces the time to wound healing and incidence of adverse events compared to commercial dressing. Therefore, the study provides systematic preclinical and clinical evidence that the silk fibroin film promotes wound healing thereby establishing a foundation towards its application for skin repair and regeneration in the clinic.

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Differing from the conventional micelles made of block or graft copolymers, in which the core and corona are connected by covalent bonding, the micelles reported in this paper are composed of a polymer pair and the core and corona are connected by hydrogen bonding. Poly(styrene-co-methacrylic acid) (SMAA) and poly(vinylpyrrolidone) (PVPo) self-assembled into spherical micelles with hydrodynamic radii around 100 nm in aqueous medium. These stable micelles are composed of the core of collapsed SMAA chains and the corona of solvated PVPo chains. The hydrogen bonding between methacrylic acid and PVPo units and the difference in the solubility in water between SMAA and PVPo are the main factors responsible for the micelle formation. Using dynamic light scattering, it was found that the hydrodynamic radius of the micelles significantly increases with increasing initial concentrations of both SMAA and PVPo. The micelle size dose not depend on the MAA content (3.55-13.1 mol %) in SMAA monotonically, which can be rationalized by the coexistence of different stabilization mechanisms. Transmission electronic microscopy (TEM) was used to observe morphologies of the micelles. The core-shell structure of the micelles became visualized only when adequate staining of the TEM specimens was employed.