Detection of Cytochrome C by Means of Surface Plasmon Resonance Sensor with TiO2-Organic Hybrid Layers

We have studied the detection of cytochrome C by the use of surface plasmon resonance (SPR) sensor on gold surface modified by TiO2-organic hybrid layer. When the (3-mercaptpropyl) trimethoxisilane film was coated on gold surface, the incident angle changed from 24.07 degrees to 25.23 degrees. Moreover, when TiO2, (anatase) layer via the thiol trimethoxysilane interfacial layer was formed, and the phosphate buffer(PB) solution was added, the incident angle was changed from 25.23 degrees to 28.15 degrees. When the cytochrome C solutions were introduced into the sample cell the peak of the resonance carve shifted to a larger incident angle. The shift of the incident angle(Delta theta) increased exponentially with the concentration of cytochrome C up to ca. 20 mu M, and the sensitivity was 0.07 mu M/0.1 degree. For the synthetic peptides, the peptides including many hydropyilic amino acid showed the highest sensitivity.