Abstract: ObjectiveTo test and verify whether Ba-alginate-Poly-L-Ornithine-Alginate microcapsules(B-PLO-A) can improve the physical properties and biocompatibility of the traditional BPA microcapsules.MethodsThe B-PLO-A and Ba-alginate-Poly-L-lysine-alginate（B-PLL-A） microcapsules were made by the static generator. The physical property of the microcapsules was evaluated by observing the morphological changes of the microcapsules in the hypotonic environment, changes in diameter of microcapsules in vitro culture and calculating broken microcapsules ratio by shaking method. The biocompatibility was observed by transplanting into peritoneal cavity of rat.ResultsB-PLO-A microcapsules are stronger and more stable in a hypotonic environment than B-PLL-A microcapsules. After 96 h mechanism shaking, the unbroken microcapsules ratio of B-PLO-A and B-PLL-A microcapsules were (99.3±1.0)% and (96.2±1.5)% respectively. The microcapsules were retrieved from peritoneal cavity of rat at 2, 4 and 8 weeks after transplantation, most of the microcapsules were of integrity, rotundity, and surface smooth without obviously bundled by connective tissue. 8 weeks after transplantation the intact microcapsules ratio of B-PLO-A and B-PLL-A microcapsules were (97.3±2.1)% and (95.4±2.4)% respectively.ConclusionB-PLO-A microcapsules as a whole have bettermechanical strength compared with B-PLL-A microcapsules, while maintaining a good biocompatibility.

Key words: Ba-alginate-poly-L-ornithine-alginate microcapsules, Ba-alginate-poly-L-lysine-alginate microcapsules, physical properties, biocompatibility