阿维菌素凝胶微球制备及其缓释性能研究

Preparation and Release Behavior of Avermectin Microspheres

摘要:

以壳聚糖和海藻酸钠作为包封材料，采用锐孔法制备了阿维菌素凝胶微球，考察了海藻酸钠、壳聚糖、氯化钙浓度及芯壁比对微球形态及包埋率的影响，利用SEM、FTIR等对微球及性质进行表征，并研究了其在土壤中的缓释性能和释药机制。经优化的制备条件为：海藻酸钠浓度3%，壳聚糖0.6%，氯化钙5%，芯壁比（v/v）为1:2，制备的载药微球形状规整，成球性良好，粒径约0.7 mm，载药量31.65%，包封率83.81%，红外光谱分析显示芯壁材料之间除氢键外没有发生化学作用。所制备的阿维菌素微球在土壤中具有缓释特性，药物释放特性符合Riger-Peppas模型，释放机理为Fick扩散。

Abstract:

Avermectin microspheres were prepared with sodium alginate and chitosan as wall material using dropping method. The effects of the concentration of sodium alginate, chitosan, calcium chloride and the ration of the core-wall on the microsphere morphology, particle size, embedding rate were investigated. The properties of microspheres were characterized by SEM and FTIR, and the release properties and mechanism in soil were studied. The experiment results showed that the optimized preparation conditions are as follows: the concentration of sodium alginate, chitosan and calcium chloride were 3%, 0.6% and 5%, respectively. The ration of core-wall was 1:2. The prepared microspheres had good spherical shape and its average diameter is about 0.7 mm, the drug content and the encapsulation efficiency were 31.65% and 83.81%, respectively. FT-IR analysis displayed there was no chemical interaction between the core and wall material in addition to the hydrogen bonding. The avermectin release characteristics of microspheres was in accord with the Riger-Peppas model, and the release mechanism was Fick diffusion.