Binding Characteristics of Zidovudine Drug with Graphene and Doped Graphene Nanostructures as Drug-Delivery Carriers: Insights from Density Functional Theory Calculations

Zidovudine (AZT) is an effective inhibitor of HIV-1 replication and the first therapeutically successful treatment of AIDS and AIDS-related diseases. In this work, we used density functional theory (DFT) at B3LYP/6-31G (d, p) level to analyze graphene (G) and doped graphene nanostructures, such as zinc-doped graphene (ZG) and boron-doped graphene (BG), as possible carriers for AZT. Comparing AZT@BG and AZT@ZG to pristine graphene, the results demonstrated a significant increase in the drug delivery of AZT. The adsorption energies for the AZT@G, AZT@BG, and AZT@ZG complexes were - 12.18, - 20.54, and - 29.14 kJ/mol, respectively. These values suggest that there are stronger interactions between AZT and Zn-doped graphene. The zinc-doped graphene interacted with the AZT drug more vigorously and had improved reactivity with an increased dipole moment in the gas and liquid phases. The results of NBO and FMO analyses exposed the facilitated transfer of charge and effective interaction between the drug and doped graphene. Moreover, the topological parameters of complexes at BCPs confirmed the non-covalent interactions within the complexes important for effective drug delivery. A little recovery time of the investigated complexes also indicated that the pristine graphene and doped graphene (BG and ZG) have potential for the drug delivery of zidovudine. To evaluate the excited-state and vibration properties of the complexes under investigation, UV-Vis and IR analyses were conducted. Thus, our study demonstrated that doped graphene nanostructures are more effective carriers for zidovudine that can help lower applied human doses and target a particular pathogen.