1. Department of Materials, Department of Bioengineering and Institute of Biomedical Engineering, Imperial College London, London SW7 2AZ, U.K.
2. Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden
3. School of Engineering, RMIT University, Melbourne, Victoria 3001, Australia
4. Department of Mathematics and Physics, North South University, Bashundhara, Dhaka 1229, Bangladesh
5. London Centre for Nanotechnology and Department of Biochemical Engineering, University College London, 17−19 Gordon Street, London WC1H 0AH, U.K.
6. ISIS Neutron and Muon Source, STFC, Rutherford Appleton Laboratory, Didcot OX11 ODE, U.K.