Assembly of Amino–Quinone Networks on Avermectin@mesoporous Silica with High Deposition to Leaf Surface

Abstract

Most traditional pesticide formulations are prone to drift and rebound, causing low effective utilization. In this study, a versatile approach is reported to engineer coatings on mesoporous silica nanoparticles (MCM-41) via the self-assembly of amine (e.g., polyethylenimine) and quinone (e.g., 5-hydroxy-1,4-naphthoquinone) networks­(AQN), a nanopesticide (Av@MCM-41@AQN) for controlled avermectin (Av) release was prepared to solve the above problems. The results showed that Av@MCM-41@AQN particles had excellent pesticide loading content (38%) and slow-release performance, and the photostability of Av@MCM-41@AQN was improved by 2.3-fold compared with the technical avermectin. Importantly, the amino–quinone networks present robust coatings with high adhesion, which can effectively inhibit the rebound of droplets on the hydrophobic base and reduce pesticide drift. The strategy reported in this study provides a way to solve the problem of low deposition efficiency and difficult residues of pesticides on leaves, which is of great significance for improving the utilization rate of pesticides.