Potential control of horseradish peroxidase immobilization on gold electrode

ArticleinScience in China Series B Chemistry 47(2):134-141 · April 2004with13 Reads
Impact Factor: 1.20 · DOI: 10.1360/03yb0106

    Abstract

    A new approach based on potential control was firstly used for the immobilization of horseradish peroxidase (HRP) as the model
    protein. The self-assembly monolayer (SAM) was prepared with 2-aminoethanethiol (AET) on the gold electrode. The charge on
    HRP was adjusted by means of the acidity of the phosphate buffer solution (PBS) for dissolving the HRP. The influence of electric
    potential on HRP immobilization was investigated by means of colorimetric immunoassay of enzyme-substrate interaction (CIESI)
    using an automatic plate reader. The HRP modified electrodes were characterized with X-ray photoelectron spectroscopy (XPS)
    as well as atomic force microscope (AFM) on template-stripped gold surface. The potential for maximum immobilization of HRP
    was near the zero charge potential. The result indicates that controlled potential can affect the course of HRP immobilization
    without the loss of enzymic activity. It is of great significance for the control of biomolecular self-assembly and the intrinsic
    electric device.