Binding Characteristics of Anticancer Drug Doxorubicin with Two-Dimensional Graphene and Graphene Oxide: Insights from Density Functional Theory Calculations and Fluorescence Spectroscopy

There has been a perpetual interest in identifying suitable nanocarriers for drug delivery. In this regard, graphene-based two-dimensional materials have been proposed and demonstrated as drug carriers. In this paper, we have investigated the adsorption characteristics of a widely used anticancer drug, doxorubicin (DOX), on graphene (G) and graphene oxide (GO) by density functional theory calculations and fluorescence and X-ray photoelectron spectroscopies. From the calculated structural and electronic properties, we have concluded that G is a better binder of DOX compared to GO, which is also supported by our fluorescence measurements. The binding of DOX to G is mainly based on strong Ï€-Ï€ stacking interactions. Consistent with this result, we also found that the sp2 regions of GO interact with DOX stronger than the sp3 regions attached with the functional groups; the binding is characterized by π-π and hydrogen-bonding interactions, respectively.