Radiolabeled dendritic probes as tools for high in vivo tumor targeting: application to melanoma

In bioimaging, targeting allows refining the diagnosis by improving the sensitivity and especially the specificity for an earlier diagnosis. Two ¹¹¹In-radiolabeled dendritic nanoprobes (DPs) (¹¹¹In-2, ¹¹¹In-3) and their model counterparts (¹¹¹In-1, ¹¹¹In-4) are designed and assessed for in vitro and in vivo tumor targeting efficiency in a murine melanoma models. Tumor uptake is correlated to dendrimer multivalency and reaches values as high as 12.7 ± 1.6% ID g^-1 at 4 h post intravenous injection for ¹¹¹In-3vs. 1.5 ± 0.5% ID g^-1 for the unfunctionalized DP, and over 11% ID g^-1 for any tumor weight whatsoever.