The dynamics of β-cyclodextrin molecules on graphene sheet. A molecular dynamics simulation study

The system composed of beta-cyclodextrins and graphene sheet in the presence and absence of water was studied utilizing molecular dynamics simulation method. The system exhibits very interesting feature, both in the presence and absence of water, beta-cyclodextrin molecules cover graphene surface but they are not strongly physisorbed to single adsorption sites. Instead, they easily slide over the graphene surface effectively forming a two-dimensional (2D) liquid phase of beta-cyclodextrin on the graphene sheet. The motion of beta-cyclodextrin in z-direction, perpendicular to graphene plane, is strongly restricted. The graphene covered by beta-cyclodextrin layer is hydrophilic, which is important and often desirable feature when considering bio and medical applications. The results of our computer experiments may contribute to the search for future use of graphene based materials in the molecular medicine and nanotribology. (C) 2019 Elsevier B.V. All rights reserved.