Structural stability of biofilms produced from silkworm cocoon fibers

Biofilms were obtained from cocoons of the silkworm, Bombyx mori, involving removal sericin, extraction and solubilization fibroin fibers, dialysis dispersions preparation biofilms by casting process. Biofilm transparency was verified UV?Vis spectroscopy thermal stability thermogravimetric/differential scanning calorimetry (TG/DSC). Soon after preparation, solidification solution prepared extracted Ajisawa method monitored until biofilm stabilized, using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) as a function time. The results showed that there change in conformation silk I structure (?-helix) to II (?-sheet). In order improve characterization LiBr Raman used verify stabilization different possible molecular conformations for fibers these materials, comparison with cocoon spectra those solid (freeze-dried precipitated 72 h. By comparing terms intensities broadened band characteristic amide I, it assess conformational changes both materials based on transitions between ?-sheet flexible ?-helix ?-turn structures. dispersion generated freeze-dried hydrogel spectrum, found be predominant. TG DSC curves higher content exhibited stability. Thus, data further elucidated properties are widely various processes.