Preparation of cyflumetofen nanocapsules and study on the controlled release performance and its field efficacy

BACKGROUND In this study, 5% cyflumetofen nanocapsules were prepared by interfacial polymerization with isophorone diisocyanate and polyethylene glycol as the reaction monomer, and tristyrylphenol polyoxyethylene ether (601-P) as the emulsifier. The physical, chemical and sustained release properties of cyflumetofen nanocapsules were characterized using scanning electron microscopy, field emission scanning electron microscopy, laser particle size analysis, Fourier transform infrared spectroscopy, contact angles testing and high-performance liquid chromatography. RESULTS The results indicated that cyflumetofen nanocapsules were spherical, with an average particle size of 100 nm, and an encapsulation efficiency and loading rate of 86% and 32%, respectively. The thermal and cold storage stabilities of cyflumetofen nanocapsules were good. Under high temperature, lower pH or a high core-wall ratio, nanoparticle release is faster. The field efficacy experiment indicated that the efficacy of cyflumetofen nanocapsules against Panonychus citri reached 97%, 30 days after spraying, significantly greater than that of a 20% cyflumetofen suspension. CONCLUSION It is important to increase the stability, lengthen the release period and improve the efficacy of cyflumetofen in cyflumetofen nanocapsules. (c) 2018 Society of Chemical Industry