Magnetic molecularly imprinted polymers used for selective isolation and detection of Staphylococcus aureus

Abstract

In this work, a novel method was developed, for isolation of S. aureus from complex (food) samples using molecular imprinting. Dopamine was used as a functional monomer and fluorescence microscopy was used for detection. Conditions for preparation of molecularly imprinted polymers (MIPs), adsorption performance, adsorption kinetic, and selectivity of the polymeric layers were investigated. The various procedures were combined in a single extraction process, with the imprinted layer on the surface of the magnetic particles (magnetic MIPs). Subsequently, MIPs were used for extraction of S. aureus from milk and rice. Moreover, raw milk from cows with mastitis was tested successfully. Using this novel MIP-based method, it was possible to detect bacteria in milk at 1 × 10³CFU·ml^-1, which corresponds to the limit set in European Union legislation for microbial control of food.

Keywords: Bacteria; Dopamine; Fluorescence microscopy; Magnetic particles; Molecularly imprinted polymers.