Fabrication, Characterization, and Insecticidal Activity Evaluation of Emamectin Benzoate–Sodium Lignosulfonate Nanoformulation with pH-Responsivity

By means of high-speed emulsification and ultrasonic dispersing, emamectin benzoate (EB)–sodium lignosulfonate (SL) nanoformulation (EBSLN_f) with a particle size of 150–250 nm was developed by the electrostatic self-assembly of SL and EB. The morphology of the nanoformulation was characterized by UV, IR, dynamic light scattering, fluorescence spectra (FS), scanning electron microscopy, and transmission electron microscopy. The results of antiphotolysis and the controlled release test for EBSLN_f showed that the antiphotolysis ability of the nanoformulation is four times higher than that of the commercial EB-emulsifiable concentrate, and the nanoformulation has a pH-responsive controlled release function. The release ratio in different pH media was acidic > neutral > basic. Moreover, the insecticidal effective duration of EBSLN_f was more than one time longer than that of EB-suspension concentrate in the greenhouse. Therefore, EBSLN_f has broad application prospects in agricultural production and environmental protection because of its easy preparation, low cost, and being environment-friendly. Thus, the strategy is suitable for large-scale industrial production.