Preparation and characterization of surface molecularly imprinted film coated on a magnetic nanocore for the fast and selective recognition of the new neonicotinoid insecticide paichongding (IPP)

Abstract

In this work, we present a general method to prepare surface molecularly imprinted film on a magnetic nanocore for new neonicotinoid insecticide paichongding (IPP) recognition. First, magnetic Fe₃O₄ nanoparticles were synthesized by a hydrothermal method and coated with SiO₂ on the surface, then were vinyl-modified to be Fe₃O₄@SiO₂@CC which was the magnetic core. After that, magnetic molecularly imprinted nanoparticles (MMIPs) were synthesized by surface-imprinted polymerization in airtight tubes at 60 °C for 24 h, using IPP as the template, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as cross-linkers. The resulting IPP-MMIPs possess specific recognition ability, fast adsorption kinetics, high adsorption capacity, and can be easily collected under an external magnetic field. The IPP-MMIPs were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), X-ray diffraction (XRD) and vibrating sample magnetometry (VSM). The binding experiments showed a relatively high adsorption capacity (17.30 mg g⁻¹) and specific recognition ability over structurally related compounds. Therefore, IPP-MMIPs have the potential to become a sensitive and selective approach for IPP recognition and separation.