1. Institute for Biomedical Engineering, University and ETH Zurich, 8092 Zurich, Switzerland
2. Laboratory of Physical Chemistry, ETH Zurich, 8093 Zurich, Switzerland
3. Laboratory for Solid State Physics, ETH Zurich, 8093 Zurich, Switzerland
4. Paul Scherrer Institut, Villigen PSI, 5232 Villigen, Switzerland
5. Particle Technology Laboratory, Institute of Process Engineering, ETH Zurich, 8092 Zurich, Switzerland