龟板水提物缓释微球的制备及其特性

目的：制备高包封率的龟板水提物缓释微球。方法：分别采用海藻酸钙凝胶珠、海藻酸钙-壳聚糖微胶囊和海藻酸钙-羧甲基纤维素钠微胶囊体系制备龟板水提物缓释微球，并考察其外观形态、包封率和体外释药等特性。结果：制得的龟板-海藻酸钙凝胶珠、龟板-海藻酸钙—壳聚糖微球和龟板-海藻酸钙-羧甲基纤维素钠微球外观圆整，表面光滑，且粒径均匀；包封率分别是46．7％、49．9％和82．3％；海藻酸钙凝胶珠有明显的突释现象，海藻酸钠—壳聚糖微球的突释现象和缓释效果有所改善，而海藻酸钙-羧甲基纤维素钠微球无突释现象，其缓释可达14小时以上。结论：龟板-海藻酸钙-羧甲基纤维素钠微球包封率高，同时具有优良的缓释性能。

Preparation of Sustained Release Microspheres of Water Extract of Plastrum Testudinis and Their Properties

Objective： To prepare the sustained release microcapsules of water extract of Plastrum Testudinis with high encapsulation efficiency. Methods： The water extract of Plastrum Testudinis-loaded microspheres were prepared respectively using these systems, calcium alginate （CA） beads, CA-chitosan （CAC） and CAC-sodium carboxymethyl cellulose （CACSCC） microcapsules. Their properties, including morphology, encapsulation efficiency and release behavior in vitro, were investigated. Results： The prepared water extract of Plastrum Testudinis-loaded CA beads, CAC and CACSCC microspheres were all spherical and smooth and their distribution of particle size were even. Their encapsulation efficiencies were 46.7% ,49.9% and 82.3% respectively. The CA beads showed significant initial burst release, the CAC microspheres showed improved release behavior and the CACSCC microspheres had the better controlled release prosperity with more than 14 h of sustained release without initial burst release. Conclusion： The water extract of Plastrum Testudinis-loaded CACSCC microspheres have a high encapsulation efficiency and a good in vitro sustained release property.