Graphene Oxide as the Potential Vector of Hydrophobic Pesticides: Ultrahigh Pesticide Loading Capacity and Improved Antipest Activity
Saijie Song, Minghui Wan, Wenli Feng, Jun Zhang, Hong Mo, Xuefeng Jiang, He Shen, Jian Shen
Abstract
The use of pesticides has made great contributions to agriculture, which ensures the high yield of crop. However, the low efficiency and overuse of pesticide has caused severe problems to the environment. Therefore, the construction of an efficient and environmentally friendly nanopesticide delivery system is of urgent need. In this work, we report PEGylated-graphene oxide (PEG-GO) as a nanocarrier for water-insoluble pesticides (e.g., emamectin benzoate, EB) delivery and investigate its antipest activity. In our strategy, through the simple physical adsorption approach, the hydrophobic EB molecule can be effectively loaded on the PEG-GO nanocarrier, forming a stable EB@PEG-GO nanoformulation. As a high performance carrier, PEG-GO exhibits ultrahigh adsorption capacity for EB (1647.2 mg/g). The as-prepared EB@PEG-GO shows excellent stability during the 2-year storage period, which is a benefit for its practical application. Compared with free EB, the advantages of EB@PEG-GO are (1) greatly improved water solubility (30 mg/mL), (2) pH-response and sustained pesticide release performance, (3) prolonged half-life under UV light irradiation (521.16 h), and (4) sustainable antipest activity. In consideration of its industrialization potential, our current results clearly demonstrate the brilliant future of GO-based nanomaterials in plant protection and agriculture.