天然可生物降解聚合物壁材在微胶囊中的应用

Microcapsules are micro⁃containers with polymer eggshells. The stability and freshness of the embedded core material of such capsules can be improved, and the release rate of the core material can be controlled effectively. However, the microcapsule wall material critically affects the final performance of a microcapsule. In this context, from the green and sustainable development perspective, the use of microcapsules with natural biodegradable polymer wall materials is gaining increasing attention. The mechanical strength, solubility, emulsification, and stability of natural biodegradable polymers meet the requirements of microencapsulation walls. Therefore, microcapsules fabricated using natural biodegradable polymers have promising application prospects in the medical, pharmaceutical, food, and cosmetic industries. Three groups of biodegradable polymers, polysaccharides, proteins and lipids, are prevalently used as natural microcapsule wall materials. This study reviews the recent literature on the use of natural biodegradable polymers as microencapsulated wall materials and discusses in detail their functional properties, encapsulation principles, microencapsulation techniques, and application prospects. It was concluded that the microcapsules prepared using polysaccharides have a low cost, better water dispersion, faster release rate, and higher utilization of core materials. The proteins have an excellent emulsification property, which results in a higher encapsulation efficiency and loading capacity of the protein⁃wall microcapsules. The lipids exhibit excellent performance in the encapsulation of hydrophilic substances. Therefore, the use of various natural biodegradable polymers as microcapsule walls should be mainstreamed in the industrial preparation of microcapsules. The investigation of the harmless modification of natural biodegradable polymers and their microencapsulation processes through molecular self⁃assembly are possible future research hotspots.