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) (In-111-2, In-111-3) and their model counterparts (In-111-1, In-111-4) 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 In-111-3 vs. 1.5 +/- 0.5% ID g(-1) for the unfunctionalized DP, and over 11% ID g(-1) for any tumor weight whatsoever.