Fabrication of HA/PEI-functionalized carbon dots for tumor targeting, intracellular imaging and gene delivery

Carbon quantum dots (CDs) as emerging carbon nano-materials have attracted tremendous attention in biomedical fields due to unique properties. In this study, hyaluronate (HA) and polyethylenimine (PEI) functionalized carbon dots (HP-CDs) were synthesized by a facile bottom-up method for tumor targeting and gene delivery. After HA modification, the HP-CDs exhibited superior dispersibility in water and good biocompatibility and were internalized readily into the cytoplasm of cancer via HA-receptor mediated endocytosis. Meanwhile, the HP-CDs with PEI functionalization were shown to have excellent gene condensation capability via electrostatic attraction and protective capacity by preventing nuclease degradation. By virtue of good photoluminescence properties, the HP-CDs as a gene carrier were successfully applied to intracellular imaging and gene delivery. Taken together, the resultant HP-CDs displayed great potential in tumor targeting, intracellular imaging and gene delivery.