Assessment of the drug delivery potential of graphene, boron nitride and their in-plane doped structures for hydroxyurea anti-cancer drug via DFT study

Abstract

Globally, cancer is the most common cause of mortality among all deadly diseases. As a result, a nanotechnology-based drug delivery system is used to improve the efficacy of cancer treatment, which provides an improved therapeutic index and delivers multiple drugs directly to the tumor site. In the present work, DFT calculations were employed to investigate the surface adsorption of a hydroxyurea (HU) anticancer drug on pristine graphene (GP), boron nitride (B₂₄N₂₄), and doped GP by replacing some of its carbon atoms with boron (B) and nitrogen (N) atoms to form C₃₀B₉N₉, C₁₆B₁₆N₁₆, and C₆B₂₁N₂₁ nanosheets. In gas media, HU is adsorbed on these C₃₀B₉N₉, C₁₆B₁₆N₁₆, C₆B₂₁N₂₁, and B₂₄N₂₄ nanosheets with adsorption energies of −0.70, −3.03, −2.47, and −1.96 eV, respectively. Alternatively, in water solvent media, the adsorption energies of C₃₀B₉N₉, C₁₆B₁₆N₁₆, C₆B₂₁N₂₁, and B₂₄N₂₄ are −0.82, −0.29, −0.15, and −0.26 eV, respectively. The energy gaps of the nanosheets were found to be 0.288, 0.174, 0.14, and 4.562 eV before adsorption, respectively. After the adsorption of HU on the proposed nanosheets, the energy gap was reduced to 0.15 eV for C₁₆B₁₆N₁₆. According to the DOS spectra, noticeable peaks appeared in the Fermi level after the adsorption of HU on the nanosheets, which indicates the reduction of the energy gap. Quantum molecular analysis predicted that the chemical potential, electrophilicity index, and nucleophilicity index of C₁₆B₁₆N₁₆ increased, whereas global hardness decreased, indicating high reactivity. Therefore, it can be concluded that among the proposed nanosheets, C₁₆B₁₆N₁₆ would be an appropriate carrier for the HU drug.