1. Physical Chemistry of Biosystems, Institute of Physical Chemistry, University of Heidelberg, D69120 Heidelberg, Germany
2. Department of Chemistry, Dainton Building, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, S3 7HF, United Kingdom
3. Nikon Imaging Center at the University of Heidelberg, BIOQUANT, D69120 Heidelberg, Germany
4. Biocompatibles UK Ltd, Chapman House, Farnham Business Park, Weydon Lane, Farnham, Surrey GU9 8 QL, United Kingdom
5. Cell Biophysics Group, Institute for Toxicology and Genetics, Karlsruhe Institute of Technology, D76131 Karlsruhe, Germany