Interaction of 5-Fluorouracil on the Surface of Graphene Oxide Nanosheets: Stability and Electronic Properties

Understanding the interaction mechanism of drug molecules on the surface of nanostructured materials is crucial for the development of effective drug delivery systems. Motivated by recent studies on the possible use of a carbon-based nanomaterial as a drug delivery substrate for the anticancer drug 5-fluorouracil (5FU) molecule, we systematically investigated the structural stability and electronic properties of its adsorption interaction on the surface of graphene oxide nanosheets (GON) by using density-functional theory calculations. The optimized structural geometry, energetic and thermal stability, dipole moment, and charge transfer of the 5FU molecule adsorption on the GON surface were determined, while the electronic properties including band structures, density of states, wave functions, and electronic charge density were analyzed. We found that both the surface epoxy or hydroxyl groups of the GON could promote the adsorption of the 5FU molecules on the surface, while the enhancement of the adsorption energy for the hydroxyl groups was greater than that for the epoxy groups on the surface. This phenomenon significantly transforms the electronic states from semiconducting to metallic via rehybridization of orbitals mediated by oxygen functional groups. Therefore, our findings suggest that the GON surfaces could serve as promising platforms for delivering the anticancer drug 5FU.