Redox and Near-Infrared Light-Responsive Nanoplatform for Enhanced Pesticide Delivery and Pest Control in Rice: Construction, Efficacy, and Potential Mechanisms

The brown planthopper, Nilaparvata lugens (Stål), is a major rice pest in various Asian countries, causing significant negative impacts on rice yield and quality. In this study, we developed a novel nanoplatform (NIT@MON@CuS) for pesticide delivery that responds to redox and near-infrared light stimuli. The nanoplatform consisted of CuS nanoparticles with mesoporous organic silica (MON), loaded with nitenpyram (NIT). With an average size of 190 nm and a loading efficiency of 22%, NIT@MON@CuS exhibited remarkable thermal response in the near-infrared region, demonstrating excellent photothermal conversion ability and stability. In vitro release kinetics demonstrated the rapid release of nitenpyram under near-infrared light and glutathione conditions, facilitating a satisfactory temperature increase and accelerated drug release. The NIT@MON@CuS-treated group exhibited a higher mortality of N. lugens, increasing from 62 to 88% compared to the group treated with nitenpyram technical after 96 h. Bioassay revealed that NIT@MON@CuS significantly enhanced nitenpyram toxicity by more than 1.4-fold against both laboratory insecticide-resistant and field strains of N. lugens. Furthermore, RT-qPCR results demonstrated that MON@CuS had the capability to reduce P450 gene expression, thereby improving the sensitivity of N. lugens to insecticides. These findings suggest that MON@CuS holds great potential as an intelligent pest control platform, offering a sustainable and efficient approach to protect crops against pests.