1. Institute for Pharmaceutical Sciences, ETH Zurich, 8093 Zurich, Switzerland, Max-Planck Institute of Colloids and Interfaces, Research Campus Golm, 14424 Potsdam, Germany, Laboratory for Surface Science and Technology, ETH Zurich, 8093 Zurich, Switzerland, and Department of Materials, Queen Mary University of London, Mile End Road, E1 4NS, London, U.K.