Structures, permeability and bio-compatibility of sericin hydrogel membranes

Research Project

Project/Area Number	11680837
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	Biomedical engineering/Biological material science
Research Institution	Shinshu University
Principal Investigator	NAGURO Masanobu Fac.Tex.sci.& Tech., Professor, 繊維学部, 教授 (70021178)
Co-Investigator(Kenkyū-buntansha)	MINOURA Norihiko National Inst.Mat.& Chem.Res., Research Leader, 物質工学工業研究所, 室長 GOTOH Yasuo Fac.Tex.Sci.& Tech., Assistant, 繊維学部, 助手 (60262698) OHKOSHI Yutaka Fac.Tex.sci.& Tech., Associate Prof., 繊維学部, 助教授 (40185236)
Project Period (FY)	1999 – 2000
Project Status	Completed (Fiscal Year 2000)
Budget Amount *help	¥3,600,000 (Direct Cost: ¥3,600,000) Fiscal Year 2000: ¥500,000 (Direct Cost: ¥500,000) Fiscal Year 1999: ¥3,100,000 (Direct Cost: ¥3,100,000)
Keywords	sericin / hydrogel / high water content / chemical cross-link / dimethylolurea / citric acid / poly (vinyl alcohol)
Research Abstract	It is recently clarified that sericin is useful as excellent functional materials. However sericin is very weak and there have not existed any practical materials in all over the world. The purpose of this project is to prepare a tough and practical sericin membrane by chemical cross-linking, and to study the relation between structure and physical property of the membrane, and to apply the membranes as a biomaterial. The membrane were prepared by cross-linking sericin and small amount of poly (vinyl alcohol) aqueous solution by dimethylolurea (DMU) and citric acid (CA) as cross-linking agents, and blending to sericin with poly (vinyl alcohol). The chemical cross-link increases with increasing DMU and CA even the extraction of the excess DMU and CA.Water content is lowered to 0.25 mole ratio of the cross-linking agent, and it increases over 0.5 again. Young's modulus shows the tendency which is reverse to the result of water content. Young's modulus of the cross-linked membranes by CA is higher than that of the membranes cross-linked by DMU. It is obvious that every hydrogel membrane prepared by blending does not dissolve in water below 40℃ and the hydrogel membranes show the tough and rubber-like properties up to about 40 wt % sericin content, because the sericin molecules bind with the amorphous PVA molecules by intermolecular hydrogen bonds. Oxygen permeability coefficients of hydrogel membranes are near the case of pure water. The contact angle of water on the surface of membranes was about 80°. These results means that these membranes are probably useful as the biomaterial such as a damage covering material and cell scaffolding material.