Theoretical appraisements on the interaction behaviour of amphetamine, ketamine and mercaptopurine drug molecules over C24 fullerene: A combined dispersion corrected DFT and MD simulation study

The present work utilizes the density functional theory (DFT) and the classical molecular dynamics simulation calculations to evaluate and understand the interaction mechanism between three illicit drug molecules Amphetamine (AMP), Ketamine (KET) and Mercaptopurine (MER) and pristine C24 fullerene. We observe that the adsorption sequence of the drug molecules in the case of gas phase is AMP > KET > MER. However, on the application of the solvent effect adsorption energy increases for the AMP and KET drug molecules over C24 indicating chemisorption behaviour. This suggests the possibility of using C24 as potential candidate for the removal application of AMP and KET drugs from environment. In the case of MER drug molecule, the interaction is a physisorption with a suitable interatomic distance and hence can be used for the detection purpose. The structural and dynamical stabilities of sensing material C24 at the room temperature has been confirmed by classical MD Simulation study. The MD calculation such as time evaluation of RMSD, RDF, energy profiles and temperature validate the DFT results.