以高压静电法制备的壳聚糖微球为模板,与海藻酸钠层层自组装制备多层聚电解质膜,再以乙酸溶出壳聚糖微球制备出微胶囊.调节乙酸的浓度及溶出时间以控制核内壳聚糖的残留量,从而诱导负电性荧光素钠的沉积.微胶囊内部荧光素钠的浓度随着包埋时间的增加而呈线性地提高,当荧光素钠溶液的浓度为2mg/1时其最终包埋的浓度达到10.2mg/1.这种聚电解质微囊对于小分子负电荷荧光素钠的释放行为主要受其囊壁和内部模板结构的影响,盐离子浓度对荧光素钠释放行为的影响较小.
Chitosan microspheres, used as template to prepare polyelectrolyte microcapsule, were prepared by high voltage electrostatic method. Polyelectrolyte membrane made of chitosan and sodium alginate was constructed layer-by-layer assembly. A little residual chitosan template can induce sediment of molecule with negative charge. Acetic acid aqueous solution was used to dissolve the chitosan template. The concentration of sodium fluorescein in the microcapsules linearly increased with time, and embeded concentration became saturated after 15 min. When concentration of sodium fluorescein solution is 2 mg/L, the saturated embeded concentration of sodium fluorescein arrived at 10.2 mg/L. The release behavior is mainly affected by microcapsule's wall and the structure of template, but concentration of NaCl has little influence on the release behaviour.