Changes of properties of Chitosan film by ^<60>Coy-Ray Irradiation

Research Project

Project/Area Number	13672064
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	補綴理工系歯学
Research Institution	Matsumoto Dental University
Principal Investigator	ITO Michio Matsumoto Dental University Professor, 歯学部, 教授 (70064681)
Co-Investigator(Kenkyū-buntansha)	MIZOGUCHI Toshihide Matsumoto Dental University Assistant, 付置研究所, 助手 (90329475)
Project Period (FY)	2001 – 2002
Project Status	Completed (Fiscal Year 2002)
Budget Amount *help	¥2,700,000 (Direct Cost: ¥2,700,000) Fiscal Year 2002: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 2001: ¥2,200,000 (Direct Cost: ¥2,200,000)
Keywords	chitosan / ^<60>Coy-Ray / natural high molecule / sterilization / Irradiation / Co^<60>γ線
Research Abstract	Due to a remarkable deterioration of material properties when chitosan film is dry-heat-sterilized, chitosan film is conventionally sterilized with the gas sterilization method However, there is a potential risk of adverse effects of gas residue on a living body system. In this study, the film was sterilized under ^<60>Coy-ray irradiation, and changes in properties were investigated. The tensile strength of chitosan film D70 (Deacetyl 70%) with a lower level of deacetyl degree markedly decreased. On the other hand, films D85 (Deacetyl 85%), and D99 (Deacetyl 99%) did not show any reduction in tensile strenghs. The tensile elongation of all films after the ^<60>Coy-ray irradiation decreased. Among them, the film (Deacetyl 70%) showed the largest reduction in tensile elongation. It was also observed that the ^<60>Coy-ray irradiation caused film discoloration of turning yellowish. The molecules of all chitosans after the ^<60>Coy-ray irradiation decreased