For the purpose of drug carrier and delivery, the polylactide was modified by polyethylene glycol blending with the weight percentage of 80/20 by two methods: solvent-casting and melt-compounding. Characterizations of X-ray diffraction, Scanning Electron Microscope and degradation experiments have been done to study the crystallization, miscibility and degradation behavior. The melt-compounding provides a better miscibility associated with longer degradation time, however the heating procedure effects the polymers. Because of the heating and cooling cycle, the polymers had an opportunity to crystalize and the crystal peak can be seen in the XRD results. While the solvent-casting avoids the high temperature experience of blend with an amorphous state, and provides lower miscibility and short degradation time. These significant features will be considerable factors in drug carrier design.

Wound dressing materials were obtained from gelatin, chitosan and nanoSiO2particles as filler. The barrier property to water vapor, water uptake ratio and antimicrobial properties of the wound dressing materials were investigated. The addition of the nanoSiO2particles endowed the materials good water uptake ratio and the barrier property to water vapor, whereas the antimicrobial agents improve the barrier property producing more hydrogen bonds. Moreover, the networks of the wound dressing materials with nanoSiO2particles displayed excellent compound binding capacity could reduce the permeation of water and increase the antimicrobial effect of the materials. The antimicrobial agents endowed the wound dressing materials with antimicrobial effect.