Preparation, Characterization, and Evaluation of Pyraclostrobin Nanocapsules by In Situ Polymerization

Abstract

In this study, pyraclostrobin nanocapsules were prepared by in situ polymerization with urea–formaldehyde resin as a wall material. The effects of different emulsifiers, emulsifier concen-trations, and solvents on the physicochemical properties of pyraclostrobin nanocapsules were in-vestigated. SolvessoTM 100 was selected as the solvent, and Emulsifier 600# was used as the emul-sifier, which accounted for 5% of the aqueous phase system, to prepare pyraclostrobin nanocap-sules with excellent physical and chemical properties. The particle size, ζ potential, and morphology of the nanocapsules were characterized by a particle size analyzer and transmission electron microscope. The nanocapsules were analyzed by Fourier-transform infrared spectroscopy, and the loading content and sustained release properties of the nanocapsules were measured. The results show that the size of the prepared nanocapsules was 261.87 nm, and the polydispersity index (PDI) was 0.12, presenting a uniform spherical appearance. The loading content of the pyra-clostrobin nanocapsules was 14.3%, and their cumulative release rate was 70.99% at 250 h, providing better efficacy and sustainability compared with the common commercial formulation.