Dummy template surface molecularly imprinted polymers based on silica gel for removing imidacloprid and acetamiprid in tea polyphenols.

Dummy template surface molecularly imprinted polymers based on silica gel were prepared through the surface molecular imprinting technique. Nonpoisonous nicotinamide, which is a structural analogue of imidacloprid and acetamidine, was chosen as the dummy template molecule. The obtained polymers were characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. The results showed that the polymers exhibited high adsorption capacity and selectivity for imidacloprid and acetamiprid. The maximum adsorption capacities of the polymers toward imidacloprid and acetamiprid were 42.05 and 22.99 mg/g, and the adsorption could reach binding equilibrium within 150 min. The polymers were successfully applied as column-filling materials to extract imidacloprid and acetamiprid from tea polyphenols with a relatively high removal rate (92.36 and 95.20%). The polymers also showed great stability and reusability during the application. The obtained polymers possessed good application prospects for removing imidacloprid and acetamiprid in tea polyphenol production processes.