PDMDAAC改性玉米醇溶蛋白负载阿维菌素纳米颗粒的制备与性能

为提高阿维菌素叶面沉积率及其抗紫外分解性能，本文设计构建了叶面亲和的纳米载体。通过自由基聚合将聚二甲基二烯丙基氯化铵（PDMDAAC）改性玉米醇溶蛋白（Zein），得到表面携带正电荷的改性玉米醇溶蛋白，并将其用于负载阿维菌素。采用红外光谱（FTIR）、扫描电镜（SEM）等手段对改性产物结构和形貌进行表征。通过反溶剂沉淀法制备了平均粒径为64.92nm的载药纳米粒子，载体对阿维菌素的包封率为(34.75±0.18)%。与植物表面的静电作用提升了纳米粒子悬浮液在植物表面的润湿性能，接触角大小随PDMDAAC接枝量增大而降低，由77.38°减小到64.60°；叶面滞留量可达33.69mg/cm²。改性玉米醇溶蛋白对阿维菌素的包覆提升了其抗紫外性能，半衰期由15min延长至40min，且阿维菌素的释放速率可通过PDMDAAC接枝率进行调控。

Preparation and properties of Avermectin-loaded PDMDAAC modified Zein nanoparticles

In order to improve the leaf deposition rate of avermectin and its resistance to UV decomposition, a foliar affinity nanocarrier was designed. By free radical polymerization, dimethyldiallylammonium chloride (PDMDAAC) was used to modify Zein, and the modified Zein with positive charge on the surface was obtained, which was used to load avermectin. The drug-carrying nanoparticles with an average particle size of 64.92nm were prepared by anti-solvent precipitation method. The encapsulation efficiency of avermectin was (34.75±0.18)%. The electrostatic interaction with the plant surface improved the wettability of the suspension, and the contact angle decreased from 77.38° to 64.60° with the increase of the amount of PDMDAAC grafting. Leaf retention reached 33.69mg/cm². Avermectin coated with modified Zein improved the UV resistance, the half-life was extended from 15min to 40min, and the release rate of avermectin was regulated by the grafting rate of PDMDAAC.