Preparation And Biocharacterization Of The Alginate Biocross-linker

Sodium alginate is a very important material in the field of tissue engineering hydrogel. They could be used in the areas of embedding enzyme, protein, medicine and cells. The purpose of this work was to prepare a novel biodegradable biocross-linker and study its characterizations.In the study, oxidation which reacts on hydroxyl groups at C-2 and C-3 positions of the sodium alginate was performed with different amount of sodium periodate. The sodium alginate dialdehyde with different numbers of aldehyde groups was prepared and their cytotoxicity, histocompatibility and biodegradability were studied. Because the aldehyde groups of sodium alginate dialdehyde could react with the amino groups of water-soluble chitosan, the biology characters of the different cross-linking hydrogel which was prepared by the sodium alginate dialdehyde with the oxidation degree of 25% and 12.5% were studied. Then, the corneal epithelia cells which were cultivated in vitro were carried by the different cross-linking hydrogel on Ch carrier and the Decement's membrane of pig. The hydrogel's biodegradability and histocompatibility in rabbit anterior chamber were studied.The results showed that the cytotoxicity of the sodium alginate dialdehyde (degree of oxidation, OD <50%) was 0～2 grades by using the MTT assay and the cytotoxicity was found to increase with increase in the degree of oxidation. And the sodium alginate dialdehyde (OD=25%) had a low lever of cytotoxicity compared with the glutaraldehyde with the same amount of aldehyde groups. In addition, the sodium alginate dialdehyde with a moderate degree of oxidation not only had a good histocompatibility as the sodium alginate but also had a better biodegradability than alginate. The different cross-linking hydrogel which was prepared by the sodium alginate dialdehyde with the oxidation degree of 25% and 12.5% didn't have the cytotoxicity and it had a good histocompatibility. The rabbit corneal epithelia cells on Ch carrier and the Decement's membrane of pig were cultivated well. The hydrogel had good biodegradability and histocompatibility in rabbit anterior chamber.In a word, the sodium alginate dialdehyde oxidized moderately is a novel, biodegradable and low cytotoxic biocross-linker. The hydrogel which is prepared by the sodium alginate dialdehyde with water-soluble chitosan is a kind of material with good biodegradability and histocompatibility. And it could be used widely in the areas of embedding enzyme, protein, medicine and cells.