Journal of Materials Science, Vol.51, No.12, 6075-6085, 2016
Surface-imprinted polymer coating l-cysteine-capped ZnS quantum dots for target protein specific recognition
This paper demonstrated a new method for preparing fluorescent molecularly imprinted polymer (MIP) for specific recognition of a target protein. The MIP-based fluorescent receptor was developed by coating MIP layer on the surface of l-cysteine modified Mn2+-doped ZnS quantum dots (QDs) using the surface molecular imprinting process. These MIP-QDs composites demonstrated fast adsorption kinetics, high stability, and good dispersibility in aqueous media. Since the fluorescence quenching of MIP-QDs composites is proportional to the concentration of the lysozyme, the MIP-based fluorescent receptor was successfully applied to the direct fluorescence quantification of lysozyme without further pretreatment. The MIP-based fluorescent receptor exhibited good selectivity and sensitivity for lysozyme detection. The optimum fluorescence intensity of the MIP-QDs was found to be at pH 6.0, and the linear range of lysozyme was from 0.1 to 2.0 mu M with the detection limit of 25.2 nM. Moreover, the proposed fluorescent receptor was satisfactorily applied to the determination of lysozyme in real samples. This study provides a new approach for recognizing and detecting of specific proteins in biological samples.