Multifunctional graphene quantum dots-conjugated titanate nanoflowers for fluorescence-trackable targeted drug delivery

Abstract

Multifunctional graphene quantum dots (GQDs) conjugated layered protonated titanate (LPT) nanoflowers have been developed as a promising system for fluorescence imaging and targeted drug delivery. The layered structure of the titanate nanoflowers provides a high specific area for loading drugs. The negatively charged nanocarrier shows a high loading capacity for doxorubicin (DOX). The fluorescence of GQDs reveals the intracellular localization of nanocarriers, suggesting that the uptake is via active endocytosis. Anti-HER2 labelling not only enables rapid uptake into HER2-overexpressing cancer cells, but also improves the nuclear accumulation of DOX. While the drug-free nanocarriers are highly biocompatible for up to 200 μg mL⁻¹, the DOX loaded nanocarriers are more potent than free DOX in anticancer therapy. It is demonstrated that the anti-HER2–GQD–LPT system is a promising platform for simultaneous cancer imaging and anticancer therapeutics.