Time-resolved surface-enhanced resonance Raman spectro-electrochemistry of heme proteins

Issue title: From Molecule to Tissue: XIII European Conference on the Spectroscopy of Biological Molecules, Palermo, Italy, August 28–September 2, 2009, Part 1 of 2

Article type: Research Article

Authors: Grosserueschkamp, Marc^; | Nowak, Christoph^; | Knoll, Wolfgang | Naumann, Renate L.C.^;

Affiliations: Max Planck Institute for Polymer Research, Mainz, Germany | Austrian Research Centers GmbH, Tech Gate Vienna, Vienna, Austria

Note: [] Corresponding author: Renate L.C. Naumann, Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany. Tel.: +49 6131 379 157; Fax: +49 6131 379 100; E-mail: naumannr@mpip-mainz.mpg.de.

Abstract: Heme proteins such as cytochrome c (cc) play a fundamental role in many biological processes. Surface-enhanced resonance Raman spectroscopy (SERRS) combined with electrochemical methods is an ideal tool to study the redox processes of heme proteins. In this context we designed a new measuring cell allowing for simultaneous electrochemical manipulation and high sensitive SERRS measurements of heme proteins. The measuring cell is based on an inverted rotating disc electrode for excitation by using a confocal Raman microscope. Furthermore, we developed a SER(R)S-active silver modified silver substrate for spectro-electrochemical applications. For this purpose silver nanoparticles (AgNPs) were adsorbed on top of a planar silver surface. The substrate was optimized for an excitation wavelength of 413 nm corresponding to the resonance frequency of heme structures. An enhancement factor of 105 was achieved. The high performance of the new measuring cell in combination with the new silver substrate was demonstrated using cc as a reference system.

Keywords: Time-resolved surface-enhanced resonance Raman spectroscopy, localized surface plasmons, silver, nanoparticles, electron transfer

DOI: 10.3233/SPE-2010-0414

Journal: Spectroscopy, vol. 24, no. 1-2, pp. 125-129, 2010