1. Competence Center for Biospectroscopy, Center for Protein Diagnostics (ProDi), Ruhr University Bochum, 44801 Bochum, Germany
2. Department of Biophysics, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44801 Bochum, Germany
3. IRsweep AG, Laubisruetistrasse 44, 8712 Staefa, Switzerland