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.