1. Department of Electronics and Biomedical Engineering, Universitat de Barcelona, 08028 Barcelona, Spain
2. Institute of Nanoscience and Nanotechnology (IN2UB), Universitat de Barcelona, 08028 Barcelona, Spain
3. Department of Inorganic and Organic Chemistry, Universitat de Barcelona, 08028 Barcelona, Spain
4. Group NABIS, Department of Biotechnology and Biomedicine, Technical University of Denmark (DTU), 2800 Kongens Lyngby, Denmark