Computer-aided design of magnetic dummy molecularly imprinted polymers for solid-phase extraction of ten phthalates from food prior to their determination by GC-MS/MS

Magnetic dummy molecularly imprinted polymers (MDMIPs) were prepared by combining the surface imprinting technique with computer simulation for selective recognition of phthalate esters (PAEs). A computational study based on the density functional theory was performed to evaluate the template–monomer geometry and interaction energy in the prepolymerization mixture. The MDMIPs were characterized by transmission electron microscopy, scanning electron microscopy, vibrating sample magnetometry, X-ray diffraction, and Fourier transform infrared spectroscopy. They exhibited (a) high saturation magnetization of 53.14 emu g⁻¹ (leading to fast separation), and (b) large adsorption capacity, fast binding kinetics, and high selectivity for PAEs. Subsequently, a molecularly imprinted solid-phase extraction procedure followed by GC-MS was established for selective extraction and determination of 10 PAEs in food samples. Under the optimal experimental conditions, the response (peak area) was linear in the 0.5–100 ng mL⁻¹ concentration range. The limits of detection ranged from 0.15 to 1.64 ng g⁻¹. The method was applied to the determination of PAEs in spiked real samples. The recoveries for 10 PAEs from various foods were in the range of 73.7%–98.1%, with relative standard deviations of 1.7%–10.2%. .