Competitive ELISA-like Label-free Detection of Lysozyme by Using a Fluorescent Monomer-doped Molecularly Imprinted Hydrogel

We report on a molecularly imprinted hydrogel for the selective fluorescent detection of a targeting protein. To achieve the fluorescent detection of proteins, a fluorescent functional monomer was synthesized with fluorescein isothiocyanate and allylamine. The monomer (FITC-AA) provided a gradable alteration of the absorption spectrum, and a decrease of the fluorescent intensity due to an interaction with the model protein, lysozyme. Also, the imprinted hydrogel (PI-gel) was simply prepared with FITC-AA, the anionic functional monomers, poly(ethylene glycol) dimethacrylate, and lysozyme by radical photo polymerization. The PI-gel showed selective adsorption for lysozyme and the imprinting factor reached to 2.7. Additionally, the PI-gel indicated a gradual decrease of the fluorescent intensity corresponding to the lysozyme concertation similar to a competitive enzyme-linked immunosorbent assay detection.