Metal-organic framework nanohybrid carrier for precise pesticide delivery and pest management

Smart core–shell nanocarriers can release pesticides in response to stimuli from the microenvironment associated with pests and the physiological behaviors of protected crops. In this work, a smart nanocarrier (MIL-101(Fe)@silica) with dual functions of site-specific delivery and plant nutrition was fabricated to deliver chlorantraniliprole (CAP) for sustainable pest management. The results showed that the developed [email protected](Fe)@silica with a size of approximately 270 nm had a stable core–shell nanostructure with a highly crystallized regular octahedron. The photostability of the drug loaded in the carrier under UV-light irradiation was 16.5 times higher than that of technical CAP. The introduction of the silica shell prevented the premature escape of CAP from the MIL-101(Fe) core in the environment and endowed the developed nanohybrid carrier with base-triggered release properties. In a laboratory bioassay, [email protected](Fe)@silica had favorable insecticidal activity (LC50 = 0.389 mg/L) in controlling Plutella xylostella larvae. After fourteen days of spraying in the greenhouse experiment, the mortality of the [email protected](Fe)@silica treatment (86%) against P. xylostella larvae was significantly higher than that of the CAP suspension concentration treatment (36.7%). In addition, MIL-101(Fe)@silica was safe for crops and could enhance the crop fresh weight and dry weight by 18.6–19.6% and 4.8–17.7%, respectively. Therefore, MIL-101(Fe)@silica could be used as a biocompatible carrier for site-specific pesticide delivery and simultaneously as a fertilizer for crop growth, which would be a novel route for the development of a precise pesticide delivery nanoplatform.