Glutathione-responsive PEGylated GQD-based nanomaterials for diagnosis and treatment of breast cancer

Graphene quantum dots-based nanoparticles (GQD-NPs) with reduction-responsive properties were synthesized via conjugation with two precursors, doxorubicin-disulfide-GQD that endowed the drug loading capability and polyethylene glycol-disulfide-Herceptin that enhanced the half-life and conferred active targeting ability towards HER2-overexpressed cancer. Disulfide linkages between the compartments are cleaved at a physiologically relevant concentration of glutathione in cancer cells, resulting a controlled release of drugs. In vitro analysis confirmed successful internalization of GQD-NPs in the cytoplasm and enhanced cellular uptake of DOX in HER2-positive breast cancer cells. The GQD-NPs show potential as a theranostic agent for HER2-overexpressed breast cancer cells.