Studying metal-doped graphene nanosheet as a drug carrier for anticancer drug β-lapachone using Density Functional Theory (DFT)

Abstract

Graphene based materials have been widely used in biomedicine as drug delivery systems in recent years. In this work, the feasibility of utilizing pure and metal–doped (Pt, Au) graphene nanosheets was investigated as a carrier for β-lapachone (β-lap) anticancer drug using quantum mechanical methods based on Density Functional Theory (DFT). The intermolecular interactions between β-lap and graphene nanosheets were studied through analyzing adsorption behavior, adsorption energy and electronic density between the drug and the graphene nanosheets in the most stable structure of β-lap/graphene complex. As Pt and Au atoms replace with one of carbon atoms in the graphene nanosheet, the metallic dopant is moved out from the sheet. The adsorption mechanism of the drug for being loaded on the graphene nanosheets was studied with current models. It was found that β-lap prefers to attach via its –O atom to pure and metal-doped graphene nanosheets. Our results disclose that the interactions between β-lap molecule and pure graphene nanosheets are weak and can be classified as physisorption. Calculations showed that Pt-doped and Au-doped graphene nanosheets have much higher adsorption energies and shorter binding distances compared to pure graphene nanosheets. The adsorption energy of β-lap molecule on Pt–doped graphene nanosheet was significantly higher than Au-doped graphene nanosheet.