Image-charge effects on peptide adsorption near graphene/water interface: A Molecular Dynamics Study*

Noncovalent functionalization of graphene by the formation of peptide-graphene complexes have been widely explored for practical applications ranging from biosenor design to drug delivery. Molecular modeling for the protein-graphene interactions and electrostatic interactions across interface is thus not only important for the predictive understanding of peptide adsorption, but also central to the rational design of such complexes. Especially, the image-charge interaction (ICI) induced by the dielectric mismatch near graphene/water interface is expected to play an important role in structural, dynamic, and thermodynamic properties of peptide adsorption. In this work, we study the adsorption of charged peptide ACE-X-NME on graphene/water interface using molecular dynamics simulations, incorporating image charge particles (ICPs) and constant potential method. We focus on elucidating the image-charge effects on binding affinity and conformation of peptide near graphe/water interface, which provide a molecular-level understanding of the interfacial peptide adsorption.