The structure and mechanical properties of A. yamamai, A. perny and B. mori silk fibroin films irradiated by gamma ray with various doses of 0, 25, 50, 100 and 200 kGy, respectively were determined by XRD, FT-IR, DSC and Instron 3365 equipment. Results showed that the aggregation structure and molecular conformation of A. yamamai, A. perny and B. mori silk fibroin films irradiated by gamma ray with those doses mentioned above were not significantly changed. However, with the increase of radiation intensity, the thermal stability of silk fibroin films declined slightly, and the breaking strength and extensibility reduced significantly, due to the breakdown of parts of secondary bonds and covalent bonds. These results suggested that, when these silk fibroin materials were sterilized by gamma irradiation, smaller radiation doses should be used, otherwise irreversible damages on these materials would be caused.

Silk fibroin （SF） hydrogels of the wild silkworm species Antheraea pernyi and Antheraea yamamai were obtained from aqueous SF solutions at room temperature. Both A. pernyi and A. yamamai solutions were slow to gelate. Hydrogels of the two species of wild silkworm were obtained rapidly following ultrasonicaton at 400–500 W. The secondary structure of the freeze-dried SF hydrogels was measured by X-ray diffraction and Fourier transform infrared spectroscopy. Ultrasonication did not change the main secondary structure of the hydrogels, but it accelerated the structural transformation of silk fibroin molecules from random coil or α helix to β sheet and reduced the gelation time.