Alternating Magnetic Field-Responsive Nanoplatforms for Controlled Imidacloprid Release and Sustainable Pest Control

In this study, an alternating magnetic field-responsive controlled-release imidacloprid (IM) nanoplatform (MRCIN) was fabricated by loading IM in yolk–shell Fe3O4@C. Fe3O4@C with a large BET surface area (312.62 m2/g) acted as a carrier for IM. Interestingly, the Fe3O4 nanoparticles in MRCIN could vibrate under varied electromagnetic fields (VEFs) to boost the release of IM. Therefore, MRCIN presented an excellent alternating magnetic field-responsive controlled-release performance via designing the frequency and voltage, which could be proved by the release curve and control efficacy experiment. After release, the existence of Fe3O4 nanoparticles was in favor of the collection of MRCIN from water. Importantly, MRCIN could be reutilized at least three times. From the viewpoint of biosafety, Fe3O4@C owned a fine biocompatibility, and MRCIN had little influence on fish and earthworm without VEF. Thus, the study provides a simple and potential way to achieve the controlled release of IM, improve utilization efficiency, and decline pollution to the environment. This system might have a good practical value in sustainable pest control and green agriculture.