Fabrication of magnetic-responsive controlled-release herbicide by a palygorskite-based nanocomposite

Abstract

In this work, a type of magnetic-responsive controlled-release herbicide (MCRH) was developed using a nanocomposite including palygorskite (Pal), ferroferric oxide (Fe₃O₄), glyphosate (Gly), and amino silicon oil (ASO). In this system, Pal with the structure of micro/nanonetworks can bind a large quantity of Gly and Fe₃O₄. The movement of Fe₃O₄ particles can be driven by a magnetic field to ensure the controlled release of pesticides. Gly, which is a type of nonselective herbicide, is widely used for weed control. In addition, ASO was selected as the coating agent to prevent Gly from rapidly releasing. In this work, the effects of the magnetic field, temperature, and coexisting ions on the release ratio of pesticides were investigated, and the results suggest that MCRH could effectively improve the utilization efficiency (UE) of Gly. In addition, zebrafish experiments indicate that MCRH has better biosafety than Gly.

Keywords: Controlled release; Herbicide; Magnetic; Nanocomposite; Palygorskite.