纳米技术可以提高农药的有效性和功能性,但是纳米农药对制剂性能的尺寸效应和相关机制还有待探索,阻碍了高效和环保纳米农药的精确设计和开发。在这项研究中,构建了两种组成相同但粒径特征不同的非载体包衣吡虫啉制剂(Nano-IMI和Micro-IMI),以排除尺寸效应研究中的其他干扰。纳米IMI和微IMI均表现出棒状结构。具体来说,纳米IMI的平均垂直轴和水平轴尺寸为239.5nm和561.8nm,而Micro-IMI表现为6.7μm和22.1μm,分别。与Micro-IMI相比,纳米IMI的小尺寸效应影响了界面分子的排列,降低表面张力和接触角,从而提高稳定性,分散性,叶面润湿性,纳米系统的沉积和保留。与Micro-IMI相比,Nano-IMI对棉桃Glover的毒性高1.3倍,归因于其提高的叶面利用效率。重要的是,Nano-IMI并没有增强对非靶标生物的毒性。本研究系统地阐明了大小效应对与有效性和安全性相关的关键指标的影响。为纳米农药的高效安全应用和可持续农业和环境发展的关键见解提供了理论基础。
Nanotechnology could improve the effectiveness and functionality of pesticides, but the size effect of nanopesticides on formulation performance and the related mechanisms have yet to be explored, hindering the precise design and development of efficient and eco-friendly nanopesticides. In this study, two non-carrier-coated imidacloprid formulations (Nano-IMI and Micro-IMI) with identical composition but varying particle size characteristics were constructed to exclude other interferences in the size effect investigation. Nano-IMI and Micro-IMI both exhibited rod-like structures. Specifically, Nano-IMI had average vertical and horizontal axis sizes of 239.5 nm and 561.8 nm, while Micro-IMI exhibited 6.7 μm and 22.1 μm, respectively. Compared to Micro-IMI, the small size effect of Nano-IMI affected the arrangement of interfacial molecules, reduced surface tension and contact angle, thereby improving the stability, dispersibility, foliar wettability, deposition and retention of the nano-system. Nano-IMI exhibited 1.3 times higher toxicity to Aphis gossypii Glover compared to Micro-IMI, attributed to its enhanced foliar utilization efficiency. Importantly, the Nano-IMI did not intensify the toxicity to non-target organism Apis mellifera L. This study systematically elucidates the influence of size effect on key indicators related to the effectiveness and safety, providing a theoretical basis for efficient and safe application of nanopesticides and critical insights into sustainable agriculture and environmental development.