99mTc-labeled oligomeric nanoparticles as potential agents for folate receptor-positive tumor targeting

One type of biocompatible nanoparticles functionalized with folate and Tc-99m was successfully synthesized. Maleimide-folic acid (Mal-FA) was selected to covalently conjugate with -SH of the nanoparticles (NPs) to prepare NPs-FA for targeting. Tc-99m was selected to conjugate with -NH2 and -SH groups of cysteine residues on the surface of NPs to prepare NPs-FA-Tc-99m for radioactive counting. The ability to target folate receptors of NPs-FA-Tc-99m was assessed in uptake studies with folate-receptor-positive human HepG2 cells. The results showed that the as-prepared NPs can selectively uptake by folate receptor-overexpressing HepG2 tumor cells in vitro. The oligomeric hybrid NPs radiolabeled with Tc-99m may develop to be SPECT/CT imaging biomaterials with high selectivity.