Self-assembly of DNA duplex in graphene bilayer

Recent studies on colloidal graphene-based materials have found that double-stranded DNAs (dsDNAs) can be trapped between stacked graphene layers in an aqueous solution and thus may open a new chapter for graphene applications. In a previous molecular dynamics simulation study of dsDNAs on a graphite surface consisting of five stacked graphene layers conducted by Zhao, two self assemblies were observed; standing up' and lying down' conformation. In this study, molecular dynamics simulations were performed on dsDNAs in graphene bilayer systems in aqueous solution. Hydrogen bond and van der Waals interaction energy were monitored and analyzed to examine the self assembly process and the interaction between dsDNAs. Our simulations showed that dsDNAs in graphene bilayer systems were able to self assemble via two possible sequential phenomena, hydrogen bond cleavage and base stacking. Weak van der Waals interactions were observed between DNAs separated by graphene layer. The number of dsDNAs in a bilayer will not influence the van der Waals interaction between DNAs separated by graphene layer.