Studies On The Properties And Biocompatibility Of Chitosan Blend Membranes In Opthlmology

Chitosan, obtained by N-deacetylation of chitin, is a naturally functional biopolysaccharides with excellent biocompatility and of no allergic reaction. It can be degradated into glucosamine and N-acetyl-glucosamine by lysozyme in vivo. Chitosan can be soluted in alkali lye or diluted acid. It has many excellent properties such as hygroscopics(moisture absorption), moistue preservation, membrane forming and wide applications in many fields such as light industry, agriculture, chemical engineering, medicine, biomedicial materials and environmental protection. As a biomacromolecule, chitosan has excellent biological compatibility, biological degradability, safety and innocuity. So the researches of chitosan as biomedicial materials have attracted recognition of the researchers in various domains especially those in materialology.In this essay, chitosan was used as the basic material of cell scaffolds in tissue engineering with several other amyloses to form the blended membranes with stated apertures. The membrane properties including the transparency, the aquiferous capacity, the surface construction, the permeation, the biological degradation degree in vitro and biological compatibility have been studied. The results show that the properties of different kinds of chitosan blended membranes have difference with the different kinds of added amyloses. But they all have high moisture absorption and transparency, a certain extent permeation and absorption of bovine serum protein and can be degradated by lysozyme in vitro. The results indicate that chitosan blended membranes have potentially broad application in the fields of biomedical membranes and carrier scaffolds in tissue engineering.Keratopathy is the secondary important factor for the blindness in clinic in the world. The culture of corneal cell in vitro is of significance to the corneal biology, pathology, pharmacology and cornea transplantation; it is also animportant part of reconstructing tissue-engineering -activated artificial cornea. In this essay, the culture methods of corneal epithelial cell and keratocytes have been studied. The culture method of rabbit corneal epithelial cells and keratocytes has been improved in order to solve the problems of epithelial cells' moving slowly, difficulty of forming monolayer, growing slowly and the keratocytes' growing slowly when the traditional tissue cultivation was adopted. The epithelia and keratocytes are properly digested by trypsin separately before processed tissue cultivation. After three days' cultivation, the corneal cells grow rapidly; one week later, the cells overspread the culture bottle. One week later, it can be observed that the epithelia and keratocytes array tightly, and have active proliferation and excellent status, which look like the corneal epithelial cell and keratocyte in vivo.Variant cornea transplantation is the only efficient way to cure cornea-blind, but the corneal transplantation materials are very devoided. Reconstructing tissue-engineering -activated artificial cornea in vitro is an effective way to solve the problem that corneal transplantation materials are devoided. In this essay, the corneal epithelial cells and keratocytes were seeded onto two different chitosan blended membranes in vitro. The cells on the membranes were observed in order to study the biocompatibility between the corneal cells and the blended membranes. The results show that the corneal epithelial cells and keratocytes can all grow well on the two different blended membranes. After being cultured one weeks on the membranes, the keratocytes exhibit spindle outline and even grow in bilayer somewhere on the membranes; the epithelial cells array tightly, having excellent status and almost overspreading the membranes' surface. It indicates that they have good compatibility with membranes and the cells' growing status in chitosan-chondroitin sulfate blended membrane is better than that in chitosan-hyaluronic acid blended membrane.On this foundation, the chitosan-chondroitin sulfate blended membrane was melio...