1. Department of Organic Chemistry, University of Barcelona, and CIBER-BBN, Networking Centre on Bioengineering, Biomaterials, and Nanomedicine, Barcelona 08028, Spain
2. Polypure AS, Martin Linges vei 25, Fornebu 1364, Norway
3. Department of Chemistry, Bioscience, and Environmental Engineering, University of Stavanger, Stavanger 4036, Norway
4. Translational Molecular Imaging, Max Planck Institute of Multidisciplinary Sciences, Göttingen 37075, Germany
5. Department of Radiology, Leiden University Medical Center, Leiden 2333, Netherlands
6. Institute for Advanced Chemistry of Catalonia (IQAC) of the Spanish Council for Scientific Research (CSIC), Barcelona 08028, Spain
7. Peptide Science Laboratory, School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4001, South Africa