A review of graphene quantum dot–layered double hydroxide nanocomposites for biomedical applications

Graphene quantum dots (GQDs, typically 2–10 nm in size) have gained attention in biomedical research due to their tunable bandgap, photoluminescence, and surface functionalization. Layered double hydroxides (LDHs), composed of divalent and trivalent cations, offer biocompatibility and controlled drug release. However, GQDs face limitations such as low yields and instability in physiological media, while pristine LDHs lack targeting ability and degrade in acidic environments. This review critically examines the synthesis, properties, and biomedical applications of GQD-LDH nanocomposites.