Exploring tiopronin adsorption on pristine and Al/Ga-doped boron nitride nanoclusters: A DFT approach for enhanced...

Tiopronin is a thiol-based medication recognized for its antioxidant properties, which may offer therapeutic benefits for various medical conditions. At present, it is utilized for the treatment of cystinuria and rheumatoid arthritis. However, its limited bioavailability poses a significant challenge for broader applications, necessitating high systemic doses to achieve localized therapeutic effects. The incorporation of a drug delivery system could help overcome this issue by allowing for controlled and targeted release. Functionalized B₁₂N₁₂ fullerenes present a promising platform with substantial potential for biomedical applications, particularly in drug delivery. In this study, the effect of loading the tiopronin drug on the structural and electronic properties of pure B₁₂N₁₂, AlB₁₁N₁₂ and GaB₁₁N₁₂ fullerenes nano agent were evaluated using density functional theory in both gas and aqueous environments. The adsorption energy of tiopronin over the fullerenes has been studied through its nucleophilic sites (COOH, NH₂, CO, and SH). Based on our analysis, the adsorption energies are about -1.69, -3.38 and -1.96 eV for the most stable complexes of B₁₂N₁₂, AlB₁₁N₁₂ and GaB₁₁N₁₂, respectively. Electronic analysis showed that the HOMO-LUMO gaps decrease upon drug adsorption, resulting in significant changes in molecular orbital levels and quantum molecular descriptors. Additionally, quantum theory of atoms in molecules (QTAIM) analysis, electron localization function (ELF), and reduced density gradient (RDG) plots were explored to investigate interaction properties.