1. Laboratories of Biophysics and Nanotechnology, Department of Experimental Medicine, University of Genova, Via A. Pastore, 3, 16132 Genova, Italy
2. Fondazione EL.B.A − Nicolini, Pradalunga, Bergamo 24020, Italy
3. The European Synchrotron, ESRF, CS40220, F-38043 Grenoble Cedex 9, France