1. London Centre for Nanotechnology University College London 17–19 Gordon Street London WC1H 0AH United Kingdom
2. Division of Medicine University College London, Cruciform Building Gower Street London WC1E 6BT United Kingdom
3. Department of Chemistry, Institute of Structural Molecular Biology University College London London WC1H 0AJ United Kingdom
4. National Physical Laboratory Teddington TW11 0LW United Kingdom
5. Department of Physics King’s College London Strand Lane London WC2R 2LS United Kingdom
6. Department of Materials Science and Engineering University of Sheffield Sir Robert Hadfield Building Sheffield S1 3JD United Kingdom