Functionalization and optimization-strategy of graphene oxide-based nanomaterials for gene and drug delivery

Graphene-family nanomaterials (GFNs) have been widely used in cancer therapy, tissue engineering, antibacterial and biological imaging due to their optical, thermal, and drug absorption properties. When used as drug and gene nanocarrier, the major limitations are aggregation, biocompatibility, and inappropriate release of drugs or genes. To overcome these problems, researchers have developed a variety of functionalization processes. In this review, we grouped the functionalization according to the decoration molecules, putting particular emphasis on the gene delivery. Organic and inorganic materials resulted as the major sets to introduce functional sections onto graphene oxide (GO). We also classified the target molecules used in the GO delivery system, as well as introduced other strategies to increase the delivery efficacy such as controlled release and magnetic targeting.