Surface Characterization Of A Cross-Linked Cytochrome C Film On Cysteamine-Modified Gold Electrodes

The aim of the present paper is to characterize a cross-linked horse heart cytochrome c (HHC) film on cysteamine-modified gold electrodes. The HHC film was deposited using 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) as a coupling agent. Attenuated total reflection infrared (ATR-IR) spectroscopic analyses were performed to characterize the newly formed surface on a qualitative and conformational level. The film thickness was measured using a noncontact optical surface profiler, while quantitative data and information on the heterogeneity of the film were obtained by means of synchrotron radiation X-ray micro fluorescence (SR micro-XRF). Results indicate that, in addition to electrochemical studies, spectroscopic analysis methods are essential to gain insight in the effect of immobilization strategies on protein conformations. The latter is of relevance in the development and optimization of biosensors. Copyright (C) 2009 John Wiley & Sons, Ltd.