Surface structure of chitosan and hybrid chitosan-amylose films-restoration of the antibacterial properties of chitosan in the amylose film.
The surface structure of films prepared by casting aqueous solutions of mixtures of water soluble chitosan (WSC) and amylose as well as a fully deacetylated chitosan was studied. Zeta potential measurements indicated that the surface of WSC and fully deacetylated chitosan films is positively charged but very weakly, whereas, a film of amylose blended with WSC exhibited an obvious positive charge. X-ray photoelectron spectra of these films suggest that less amino groups are exposed on the surface of WSC and fully deacetylated chitosan films, whereas, more amino groups are exposed on the surface of a WSC film blended with amylose. A sheet structure in which free amino groups are less exposed on the surface of the film of WSC or fully deacetylated chitosan is proposed. This accounts for the loss of antibacterial activity of chitosan on the WSC film surface. When blended with amylose, the morphology of the film may be disrupted, resulting in strong antibacterial properties.
Graduate School of Life and Environmental Sciences, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
Shiho
S
Suzuki
Bo
B
Ying
Hideki
H
Yamane
Hideki
H
Tachi
Katsumasa
K
Shimahashi
Kozo
K
Ogawa
Shinichi
S
Kitamura
D000688:Amylose / Q000737:chemistry* / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology; D048271:Chitosan / Q000737:chemistry* / Q000494:pharmacology; D013057:Spectrum Analysis; D013499:Surface Properties; D014965:X-Rays
D000900:Anti-Bacterial Agents; D000688:Amylose; D048271:Chitosan