1. Nanomaterials for Bioimaging Group (nanoBIG), Departamento de Física de Materiales, Facultad de Ciencias, Universidad Autónoma de Madrid, C/Francisco Tomás y Valiente 7, Madrid, 28049, Spain
2. Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
3. Department of Chemistry, Nanoscience Centre, University of Jyväskylä, P.O. Box 35, FI-40014, Finland
4. Phantom-g, CICECO – Aveiro Institute of Materials, Department of Physics, Universidade de Aveiro, 3810-193, Aveiro, Portugal
5. Nanomaterials for Bioimaging Group (nanoBIG), Instituto Ramón y Cajal de Investigación Sanitaria, Hospital Ramón y Cajal, Ctra. De Colmenar Viejo, Km. 9100, 28034, Madrid, Spain