Surface Modification of Graphene and its Derivatives for Drug Delivery Systems

Nowadays, carbon-based nanostructure materials are regarded as promising carriers for drug delivery to improve the effective treatment of diseases. The formation of covalent and noncovalent molecular bonds can be used for surface modification of nano-carriers in order to manipulate their toxicity, water solubility, and cellular internalization. Graphene and its derivatives have shown important potential in drug delivery systems. Among different graphene derivatives, Graphene Oxide (GO) is the most extensively used derivative. GO sheets have possessed certain oxygen functional groups including carboxylic acid groups at the edges, epoxy and hydroxyl groups on the basal planes. The oxygen groups on the surface of GO sheets enhance their capabilities for functionalization with chemical and bioactive molecules. In this review, we highlight the recent researches about the effect of reactive sites on the surface of GO and its derivatives in drug delivery systems. Therefore, the application of GO and its derivatives have been discussed as a delivery system in cancer treatment, gene therapy, and combination therapy, followed by discussions on their related issues. Finally, the review will provide a future perspective to the applications of GO-based materials as part of drug delivery systems, and may open up new viewpoints to motivate broader interests across these interdisciplinary fields.