The effect of methanol treatment on the thermal properties and secondary structure of Eri Samia ricini silk fibroin/chitosan blend filmsAuthor(s): Prasong Srihanam
This study was aimed to prepare Eri silk fibroin (SF)/chitosan (CS) blend films with different blend ratios by a solvent evaporation method in comparison with that of both native SF and CS films. The blend films were used as subject material for study the effect of methanol treatment. The properties of the blend films including morphology, secondary structure and thermal decomposition were investigated by using scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectrometer and thermogravimetric analysis (TA), respectively. The native SF and CS films were appeared homogeneous throughout the film surface and matrix without phase separation. All SF/CS blend films showed both SF and CS characteristics. FTIR results indicated that the SF and blend films were composed of a higher proportion of -sheet structure after methanol treatment. The results of thermal decomposition obtained from TA instrument suggested that SF and CS were formed of intermolecular bonds, especially H-bonds. Those of films showed that increasing SF contents resulted in an increase in -sheet structure. In addition, it was shown that the thermal stability of the SF/CS blend films could be affected by blend ratio as well as methanol treatment. The results in this study implied that the SF/CS blend films treatment with methanol would be used for various fields including drug controlled release, cell culture or medical applications.