1. Institute of Medical Physics and Biophysics, University of Leipzig, Leipzig, Germany
2. Institute of Analytical Chemistry, University of Leipzig, Leipzig, Germany
3. Paul Flechsig Institute for Brain Research, University of Leipzig, Leipzig, Germany
4. Department of Cell and Chemical Biology, Laboratory for Neurophysiology, Leiden University Medical Center, Leiden, The Netherlands
5. Leiden Institute of Chemistry, Leiden University, Leiden, The Netherlands