Abstract: Complex coacervation is commonly used to make sustained-release gelatin microcapsules, this article overviewed its application field, preparation process and influence factors, investigated the effects of successfully making sustained-release gelatin microcapsules through the concentration and ratio of gelatin and the other condensed-phase, temperature of reaction system, stirring speed, pH, level of crosslink and drying process.

Key words: complex coacervation; gelatin; sustained-release microcapsules