Investigation of the interaction of amphetamine drug with Zn12O12 nanocage: a quantum chemical study

The interaction of amphetamine (AM) drug with a zinc oxide (Zn 12 O 12 ) nanocage was studied based on the density functional theory (DFT) in a B3LYP/LANL2DZ level of theory. The adsorption energy of the AM drug on the Zn 12 O 12 surface was calculated to be about −14.09 kcal/mol, and this value confirmed the physical adsorption of the drug on the Zn 12 O 12 surface. Also, based on the natural bond orbital (NBO) analysis, charge transfer occurred from the drug to the nanocage, and the value of charge was calculated to be about −0.139 e. In addition, both molecular orbitals show that the LUMO and HOMO are mostly located on the surface of the Zn 12 O 12 nanocage. The mechanism of the sensors depends on the difference between the corresponding levels, which is also correlated with changes in electrical conductivity. The electrical conductivity of Zn 12 O 12 was increased about 31.30% after AM drug adsorption.