DFT Study on the Interaction of Paracetamol and Torsional Deformed Graphene

Abstract

The interaction between paracetamol molecule and graphene sheet and the influence of torsional deformation on it were studied on the basis of density functional theory. Our results show that paracetamol molecule is physically adsorbed on the graphene sheet in a parallel adsorption model. Torsional deformation can change the bonding strength between paracetamol and graphene sheet, so by adjusting the deformation, the sustained and controlled release of drugs may be achieved. The results of global reactivity descriptors show that the stability of paracetamol-graphene complex is reduced by the presence of graphene, but the chemical activity is improved. The effect of torsional deformation is opposite to that of graphene. The paracetamol-graphene complex is easy to bond with electrophilic groups. The increased strain decreases the electrophilic ability of paracetamol-graphene complex. Analysis confirms that global reactivity descriptors have reasonably good correlation with the solubility and dispersion of paracetamol graphene complex,but they cannot be used to determine the pharmacological activity of drugs. Analysis of frontier orbitals and Fukui indices suggests that the active sites of the paracetamol include benzene rings, phenolic hydroxyl groups (electrophilic active site) and carbonyl group (both the nucleophilic and electrophilic active sites). For paracetamol-graphene complex, the active sites are mainly distributed from the graphene, there is almost no the active sites distribution on the paracetamol molecule. Hence, we can deduce that paracetamol will not exert its efficacy before it dissolves from the paracetamol-graphene complex, as a result, the efficacy of the paracetamol can be controlled by graphene carriers.