Evaluation of the active targeting of melanin granules after intravenous injection of dendronized nanoparticles
Résumé
The biodistribution of dendronized iron oxides, NPs10@D1_DOTAGA and melanin-targeting NPs10@D1_ICF_DOTAGA, was studied in vivo using MRI and planar scintigraphy through [177Lu]Lu-radiolabeling. MRI experiments showed high contrast power of both dendronized nanoparticles (DPs) and hepatobiliary and urinary excretions. Little tumor uptake could be highlighted after intravenous injection probably as a consequence of the negatively charged DOTAGA-derivatized shell which reduces the diffusion across the cells' membrane. Planar scintigraphy images demonstrated a moderate specific tumor uptake of melanoma-targeted [177Lu]Lu-NPs10@D1_ICF_DOTAGA at 2 h post intravenous injection, and the highest tumor uptake of the control probe [177Lu]Lu-NPs10@D1_DOTAGA at 30min pi, probably due to the enhanced permeability and retention (EPR) effect. In addition, ex vivo Confocal microscopy (EVCM) studies showed a high specific targeting of human melanoma samples impregnated with NPs10@D1_ICF_Alexa647_ DOTAGA.