Hierarchical Self-Assembly of Noncanonical Guanine Nucleobases on Graphene.

ABSTRACT: Self-assembly characterizes the fundamental basis toward realizing the formation of highly ordered hierarchical heterostructures. A systematic approach toward the supramolecular self-assembly of free-standing guanine nucleobases and the role of graphene as a substrate in directing the monolayer assembly are investigated using the molecular dynamics simulation. We find that the free-standing bases in gas phase aggregate into clusters dominated by intermolecular H-bonds, whereas in solvent, substantial screening of intermolecular interactions results in ?-stacked configurations. Interestingly, graphene facilitates the monolayer assembly of the bases mediated through the base-substrate ?-? stacking. The bases assemble in a highly compact network in gas phase, whereas in solvent, a high degree of immobilization is attributed to the disruption of intermolecular interactions. Graphene-induced stabilization/aggregation of free-standing guanine bases appears as one of the prerequisites governing molecular ordering and assembly at the solid/liquid interface. The results demonstrate an interplay between intermolecular and ?-stacking interactions, central to the molecular recognition, aggregation dynamics, and patterned growth of functional molecules on two-dimensional nanomaterials.

SUBMITTER: Saikia N 

PROVIDER: S-EPMC6641521 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature