Keratin solution was separately blended with collagen, gelatin, sericin and starch for films preparation. All the blended films had smooth surfaces without phase separation, except the keratin/ starch blend film. The native keratin film showed small particles embedded in all the film surfaces that resulted in them being rough. The structure of the native keratin film changed from beta-sheet to random coil at high blend ratio of other substances. This result increased the dissolution of the films especially the keratin/starch blend. The results relate directly to the decreased thermal stability of this film. However, the changes in structure did not affect the chlorhexidine release pattern. It is possible that the interaction between the drug and blending substances, and the substances to water molecules are the main factor influencing the drug release pattern from the films.

This research was aimed to investigate the effect of cross-linked agents on the properties of keratin films. The films were prepared by mixing all solutions until homogeneous before pouring into polystyrene plates and dried in an oven at 40 o C for 3 days. The obtained films were characterized for their morphology and secondary structure using scanning electron microscope (SEM) and Fourier transform-infrared (FT-IR) spectrophotometer. The native keratin film had smooth surfaces with slight fragile throughout the film area. Considering among the cross-linked agent, the keratin film cross-linked with glutaraldehyde had the smoothest surfaces than others. In addition, the differences of cross-linked agents were affected on different morphology of the films. The secondary structure analysis found that random coil structures of films had been changed into β-sheet after blending with cross-linked agent. This reflected to increase of dense texture, strength and thermal stability of the films. The results could be suggested that the morphology, secondary structure and thermal stability of the keratin films were depended on content and type of cross-linked agents used.