Summary: The thermal and structural analysis of silk fibroin (SF) and silk sericin (SS) blend films reveals that the crystallization of SF is retarded in the presence of SS. Although a phase separation was observed, there might be a strong interaction at the boundary of the SF and SS through intermolecular hydrogen bonding, which restricts the conformational transition of SF.
TEM image of the cross‐section of the SF/SS blend (75:25) film (magnification: ×15 000). 相似文献
Silk fibroin is a useful protein polymer for biomaterials and tissue engineering. In this work, porogen leached scaffolds prepared from aqueous and HFIP silk solutions were reinforced through the addition of silk particles. This led to about 40 times increase in the specific compressive modulus and the yield strength of HFIP‐based scaffolds. This increase in mechanical properties resulted from the high interfacial cohesion between the silk matrix and the reinforcing silk particles, due to partial solubility of the silk particles in HFIP. The porosity of scaffolds was reduced from ≈90% (control) to ≈75% for the HFIP systems containing 200% particle reinforcement, while maintaining pore interconnectivity. The presence of the particles slowed the enzymatic degradation of silk scaffolds.
Sericin removal from the core fibroin protein of silkworm silk is a critical first step in the use of silk for biomaterial‐related applications, but degumming can affect silk biomaterial properties, including molecular weight, viscosity, diffusivity and degradation behavior. Increasing the degumming time (10, 30, 60, and 90 min) decreases the average molecular weight of silk protein in solution, silk solution viscosity, and silk film glass‐transition temperature, and increases the rate of degradation of a silk film by protease. Model compounds spanning a range of physical‐chemical properties generally show an inverse relationship between degumming time and release rate through a varied degumming time silk coating. Degumming provides a useful control point to manipulate silk's material properties.
Native silk fibroin (NSF) is a unique biomaterial with extraordinary mechanical and biochemical properties. These key characteristics are directly associated with the physical transformation of unstructured, soluble NSF into highly organized nano‐ and microscale fibrils rich in β‐sheet content. Here, it is shown that this NSF fibrillation process is accompanied by the development of intrinsic fluorescence in the visible range, upon near‐UV excitation, a phenomenon that has not been investigated in detail to date. Here, the optical and fluorescence characteristics of NSF fibrils are probed and a route for potential applications in the field of self‐assembled optically active biomaterials and systems is explored. In particular, it is demonstrated that NSF can be structured into autofluorescent microcapsules with a controllable level of β‐sheet content and fluorescence properties. Furthermore, a facile and efficient fabrication route that permits arbitrary patterns of NSF microcapsules to be deposited on substrates under ambient conditions is shown. The resulting fluorescent NSF patterns display a high level of photostability. These results demonstrate the potential of using native silk as a new class of biocompatible photonic material. 相似文献
Silk reinforced silk-fibroin-based composites were prepared by embedding of silk textile into regenerated silk fibroin(RSF)matrix. The breaking stress and breaking strain of the composites were found 37.7 MPa and 71.1% respectively at(95 ± 5)% RH.Morphological analysis was carried out to observe fracture behavior of the samples. The in vitro biodegradation test showed that the composite degraded slowly and lost 70% weight at the end of 168 h. Moreover, compared with RSF pure film, the composite kept strength and toughness much longer time. In conclusion, this composite has the potential for more accurate cytology research and biomedical tests in the future. 相似文献