Abstract: Molecularly imprinted microspheres (MIMs) were prepared by precipitation polymerization for the binding and recognition of 1,4-hydroxybenzoic acid esters. Ethyl p-hydroxybenzoate (EtPHB) was used as the template molecule, methacrylic acid as the functional monomer, ethylene dimethacrylate as the linking agent. It was evaluated by solid-phase extraction column packed with MIMs combined with liquid chromatography to determine trace preservatives including benzoic acid, methyl p-hydroxybenzoate, EtPHB, propyl p-hydroxybenzoate in food products. A solid-phase extraction based on MIM procedure was used to isolate four additives from the food matrix before quantitative analysis. The Scatchard plot suggested that the template - polymer system had two-site binding behavior with the dissociation constants of 0.3577 and 3.952 mg/g, respectively. The rebinding test, based on the molecularly imprinted solid-phase extraction column technique, showed the recoveries of soy samples spiked with four additives within 88.4 - 110.6%, with the relative standard deviations of 1.97â€"3.82%. Finally, the method was successfully applied for the analysis of parabens in foodstuff without traditional pretreatment
Template and target information: 1,4-hydroxybenzoic acid esters, ethyl p-hydroxybenzoate, EtPHB, benzoic acid, methyl p-hydroxybenzoate, propyl p-hydroxybenzoate, parabens
Author keywords: Ethyl p-hydroxybenzoate, molecularly imprinted microspheres, precipitation polymerization, Solid-phase extraction, Soy sample