Shen Yue, Zhu Huaxin, Cui Jianxia, Wang Anqi, Zhao Xiang, Cui Bo, Wang Yan, Cui Haixin
Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Nanomaterials (Basel). 2018 Dec 6;8(12):1016. doi: 10.3390/nano8121016.
Traditional pesticide formulations are limited by large organic solvent consumption, poor dispersibility, and poor foliar adhesion, resulting in low effective pesticides utilization and environmental pollution. To prolong the foliar pesticide retention and release time, a high lambda-cyhalothrin (LC)-loaded nano-delivery system was constructed, using polylactic acid (PLA) as a carrier through a solvent evaporation method. The obtained results showed that the stabilizer concentration, water⁻oil ratio, and carrier content exert a major influence on the LC loading, particle size, and size distribution. The prepared LC/PLA nanoparticles have a uniform spherical shape with a smooth surface. The size of the nanoparticles was less than 200 nm, and the LC loading capacity reached up to 46.6 wt.%, with a high encapsulation efficiency (exceeding 90%). Adjustment of the shear and ultrasonic time changed the size of the nanoparticles. Significant differences were found in the sustained release properties of LC/PLA nanoparticles with different LC loadings. The foliage adhesion of the LC nano-delivery system far exceeded that of the commercial LC formulation due to a low surface tension and a low contact angle, this foliage adhesion would greatly help to improve pesticide utilization.
传统农药制剂存在有机溶剂消耗量大、分散性差和叶面附着力差等问题，导致农药有效利用率低且造成环境污染。为延长叶面农药滞留和释放时间，采用溶剂蒸发法，以聚乳酸（PLA）为载体构建了高含量氯氟氰菊酯（LC）的纳米递送系统。结果表明，稳定剂浓度、水油比和载体含量对LC负载量、粒径和粒径分布有重大影响。制备的LC/PLA纳米颗粒呈均匀球形，表面光滑。纳米颗粒尺寸小于200 nm，LC负载量高达46.6 wt.%，包封率高（超过90%）。调整剪切和超声时间可改变纳米颗粒的尺寸。不同LC负载量的LC/PLA纳米颗粒的缓释性能存在显著差异。由于表面张力低和接触角小，LC纳米递送系统的叶面附着力远远超过市售LC制剂，这种叶面附着力将极大地有助于提高农药利用率。
