Fabrication of abamectin-loaded mesoporous silica nanoparticles by emulsion-solvent evaporation to improve photolysis stability and extend insecticidal activity.

: Mesoporous silica nanoparticles (MSNs) can be designed to effectively load, protect, and control the release of pesticides. In this study, emulsion-solvent evaporation was used to fabricate abamectin-loaded MSNs. Our method could deliver abamectin in the process of MSN self-assembly, resulting in simple operation, short preparation period and outstanding drug carrying capacity. The characteristics of abamectin-loaded MSNs, including morphology, loading content, stability against photolysis, controlled release behavior, and toxicological effect, were systematically investigated. Abamectin-loaded MSNs were successfully produced with spherical shape, rough surface, uniform particle sizes, typical hollow structure, high loading efficiency (44.8%), excellent photodegradation-reducing ability, and controlled-release properties. The biological activity survey for abamectin-loaded MSNs showed excellent toxicological properties againstPlutella xylostellalarvae and maintained biological activity until the 15th day with 70% mortality of the target insect. The results of this study are beneficial for the development of a delivery system for the rational and effective usage of pesticides.