新型核-壳结构纳米农药的制备及其抗植物病毒生物活性研究

The application of pesticide played a significant role in the management of seriously agricultural diseases and ensuring agricultural production. Recently, with the changes of ecological condition, crop varieties, and farming system, plant viral diseases happened dramatically in our country, which resulted in the extension of applying pesticide. However, the unbounded use of pesticide led to unfavorable outcomes either to plants, environment, non-target organisms, or to food safety, which ultimately poses dangers to public health. However, controlled release of pesticide played an important role in the management of crop diseases and disasters, due to its advantage in improving efficacy, reducing dosing frequency, increasing safety, and reducing environmental pollution. Herein, we will systematically study the core-shell nanoparticles assembled from polymers and proteins for discovering nanocarriers with good environmental compatibility to encapsulate antiviral agents. And on this basis, the pesticide quantum of encapsulation, the release rate and efficacy of nanoparticles will be evaluated. This proposal will provide some scientific references and technology in efficiently and securely using of pesticide and managing plant viral diseases.

农药在防控农作物重大病害灾害及保证农业生产上发挥了至关重要的作用。近年来，随着生态条件、品种和耕作制度的不断改变，植物病毒病在我国大规模发生并流行，加大了农药的使用力度，但也伴随着农药带来的负面因素：农药的低效使用，未被利用和降解的农药带来的生态破坏、环境污染、对非靶标生物的威胁及食品安全问题，而农药的缓释可以提高农药的高效使用、减少给药频率、增加安全性和降低环境污染的风险。由此，本课题将对由高分子聚合物和蛋白分子形成的核-壳结构进行系统的研究，期望获得具有良好环境相容性的核-壳纳米载体用来包裹抗病毒剂，在此基础上评价农药的包裹量、释放速度、药效等指标，为农药的高效、安全使用及植物病毒病的防控提供一定的科学参考和技术积累。

按计划开展了各项研究工作，合成了含3-吡啶基团的聚(甲基丙烯酸羟乙酯)高分子聚合物pHEMA-pyridine（分子量约36 K），通过优化高分子与模型蛋白（牛血清蛋白，BSA）的质量比制备出了可用于装载抗病毒药剂（病氰硝或病毒唑）的核-壳纳米组装体（PyPHEMA@BSA），替换模型蛋白为廉价易得的大豆乳清蛋白（SWP）获得了具有应用潜力的核-壳纳米组装体（PyPHEMA@SWP）。在此基础上评价了对抗病毒药剂的包裹量、释放速度、药效等指标，发现制备的核-壳纳米结构可高效装载抗病毒剂，且对pH和尿素具有响应性。同时，制备的核-壳纳米农药提高了在叶面上的铺展能力，进而提升了抗病毒剂的药效和生物利用度。上述研究结果为农药的高效、安全使用及植物病害的综合防控提供了一定的科学参考和技术积累。