A study on the flow stability of regenerated silk fibroin aqueous solution

The flow stability of silk fibroin (SF) aqueous solutions with different concentrations under different temperatures was investigated. It was found that the flow stability decreased quickly with the increase of solution concentration and temperature. X-ray diffraction, Fourier transform infrared (FTIR) and Raman spectroscopy analysis showed that silk fibroin in aqueous solution was mainly in random coil and α-helix conformation. However, it turned into α-helix and β-sheet conformation after gelation, and both silk I and silk II crystalline structures appeared accordingly. The investigation implies that the original dilute regenerated SF aqueous solution should be stored under low temperature and concentrated just before spinning.