1. Research Group Biotechnology and Biomedicine, Peter Debye Institute for Soft Matter Physics Leipzig University Linnéstraße 5 04103 Leipzig Germany
2. Leibniz Institute of Surface Engineering (IOM) Permoserstraße 15 04318 Leipzig Germany
3. Division of Surface Physics, Felix Bloch Institute for Solid State Physics Leipzig University Linnéstraße 5 04103 Leipzig Germany