Li Wenjing, Wang Qi, Zhang Fang, Shang Hui, Bai Shiyang, Sun Jihong
Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, People's Republic of China.
R Soc Open Sci. 2021 Feb 17;8(2):201967. doi: 10.1098/rsos.201967.
In this study, we synthesized pH-sensitive thiamethoxam-3-(2-aminoethylamino) propyl-bimodal mesoporous silica (P/Thi-NN-BMMs) nanoparticles (NPs). We used this bimodal mesoporous silica (BMMs) mesoporous material as a carrier based on the principle of free radical polymerization. The size of the P/Thi-NN-BMMs NPs was about 891.7 ± 4.9 nm, with a zeta potential of about -25.7 ± 2.5 mV. X-ray powder diffraction analysis, N-sorption measurements and thermogravimetric analysis indicated that thiamethoxam (Thi) was loaded into the pores of the mesoporous structure and that the mesopore surface was coated with polyacrylic acid (PAA). The loading rate of P/Thi-NN-BMMs was about 25.2%. The controlled-release NPs had excellent anti-photolysis performance and storage stability. The NPs showed significant pH sensitivity, and the Thi release rate in pH 10.0 phosphate buffer was higher than those in pH 7.4 and pH 3.0 phosphate buffers. We described the sustained-release curves according to the Weibull model. The relative toxicity of P/Thi-NN-BMMs against peach aphid was 1.44 times that of commercial Thi. This provides a promising instrument for effective insect control and environment protection.
在本研究中，我们合成了pH敏感型噻虫嗪-3-(2-氨乙基氨基)丙基-双峰介孔二氧化硅（P/Thi-NN-BMMs）纳米颗粒（NPs）。基于自由基聚合原理，我们使用这种双峰介孔二氧化硅（BMMs）介孔材料作为载体。P/Thi-NN-BMMs NPs的尺寸约为891.7±4.9 nm，zeta电位约为-25.7±2.5 mV。X射线粉末衍射分析、N吸附测量和热重分析表明，噻虫嗪（Thi）被负载到介孔结构的孔中，且介孔表面涂覆有聚丙烯酸（PAA）。P/Thi-NN-BMMs的负载率约为25.2%。控释NPs具有优异的抗光解性能和储存稳定性。NPs表现出显著的pH敏感性，在pH 10.0磷酸盐缓冲液中的Thi释放速率高于在pH 7.4和pH 3.0磷酸盐缓冲液中的释放速率。我们根据威布尔模型描述了缓释曲线。P/Thi-NN-BMMs对桃蚜的相对毒性是市售噻虫嗪的1.44倍。这为有效防治害虫和环境保护提供了一种有前景的手段。
