Magnetic resonance imaging (MRI) relies on appropriate contrast agents, especially for visualizing transplanted cells within host tissue. In recent years, compounds containing fluorine-19 have gained significant attention as MRI probe, particularly in dual 1H/19F-MR imaging. However, various factors affecting probe sensitivity, such as fluorine content and the equivalency of fluorine atoms, must be considered. In this study, we synthesized fluorinated micelles with adjustable surface positive charge density and investigated their physicochemical properties and MRI efficacy in phantoms and labeled cells. While the micelles exhibited clear signals in 19F-MR spectra and imaging, the concentrations required for MRI visualization of labeled cells were relatively high, adversely affecting cell viability. Despite their favourable physicochemical properties, achieving higher labeling rates without compromising cell viability during labeling remains a challenge for potential in vivo applications.

3rd Faculty of Medicine Charles University Ruská 87 Prague 100 00 Czech Republic

Department of Physical and Macromolecular Chemistry Faculty of Science Charles University Hlavova 8 Prague 128 00 Czech Republic

Faculty of Health Studies Technical University of Liberec Studentská 1402 2 Liberec 461 17 Czech Republic

Institute for Clinical and Experimental Medicine Vídeňská 1958 9 Prague 140 21 Czech Republic

Institute of Biophysics and Informatics 1st Faculty of Medicine Charles University Kateřinská 1660 32 Prague 121 08 Czech Republic

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