A Computational Study on Melphalan Adsorption on the Surface of Graphene Quantum Dots

In this study, Melphalan interaction with graphene quantum dots was evaluated by infra red (IR), natural bond orbital (NBO) and frontier molecular orbital (FMO) computations. The negative values of adsorption energy, enthalpy changes, Gibbs free energy variations showed melphalan adsorption on the surface of graphene quantum dots is exothermic, spontaneous and experimentally feasible. Structural parameters including the energy of HOMO and LUMO orbitals, bandgap, electrophilicity, chemical potential, chemical hardness, density and zero-point energy were also calculated and discussed. The remarkable decrease in bandgap after the melphalan adsorption on the surface of graphene quantum dots demonstrated that the electrochemical conductivity and electrocatalytic properties increased after adsorbate interaction with the adsorbent and graphene quantum dots can be used for the construction of new electrochemical sensor in order to melphalan detection and quantitation. The remarkable decrease in bandgap after the melphalan adsorption on the surface of graphene quantum dots demonstrated that the electrochemical conductivity and electrocatalytic properties increased after adsorbate interaction with the adsorbent and graphene quantum dots can be used for the construction of new electrochemical sensor in order to melphalan detection and quantitation.