Enza Di Gregorio1, Giuseppe Ferrauto1, Eliana Gianolio1, Daniela Delli Castelli1, Silvio Aime1
1Molecular Biotechnology & Health Sciences, Molecular Imaging Center, Torino, Italy
Different strategies to label cells with paramagnetic MRI contrast agents have been exploited in the last years like pinocytosis, electroporation, receptor/transporter mediated endocytosis, external labeling. Herein we show that hypotonic swelling of cells is a new efficient route to label cells with paramagnetic Gd-complexes. In fact, the cytoplasmatic uptake shifts to much higher loadings the quenching effect on the relaxivity observed when the paramagnetic Gd-complexes are compartmentalized into endosomal vesicles.