The roles of gold and platinum decoration and trapping on the B₁₂N₁₂ fullerene in improving the antitumor efficacy of ifosfamide: A DFT and spectroscopic study

Using density functional theory (DFT) calculations, the loading of Ifosfamide (IFO) via it's the phosphoryl (P = O) group onto the surface of Pt@B₁₂N₁₂, Au@B₁₂N₁₂, B₁₂PtN₁₂, and B₁₂AuN₁₂ fullerene like-cages in vacuum and water environments were studied for the analysis. We observed that the trapping of Pt and Au atoms within the B₁₂N₁₂ fullerene-like cages enhances the binding energy during interaction with IFO, compared to when Pt and Au atoms are decorated onto the B₁₂N₁₂ in both vacuum and water phases. The polarity of the IFO/B₁₂AuN₁₂ complex (18.43 Debye) is enhanced compared to the IFO/Au@B₁₂N₁₂ complex (16.67 Debye), which is significant for effective in vivo drug delivery. These changes contributed to a slight enhancement in binding energy observed with the trapping of Pt and Au atoms into the fullerene in a water environment compared to the vacuum environment. Quantum molecular descriptor analysis indicates that the decline in hardness and electrophilicity leads to a decrease in the energy gap, which in turn enhances the polarizability of the electron cloud. The theoretical infrared (IR) spectrum indicates that the vibrational frequency of the P = O group in the drug changes upon interacting with the Pt@B₁₂N₁₂, Au@B₁₂N₁₂, B₁₂PtN₁₂, and B₁₂AuN₁₂ fullerene-like cages, and this change is consistent with the experimental data. The electronic characteristics of Pt@B₁₂N₁₂ as a biosensor are highly responsive to the presence of IFO molecules compared to Au@B₁₂N₁₂, resulting in a significant change in the energy gap of the fullerene-like cage after the adsorption process: 50.26 % in the water phase and 114 % in the vacuum phase. These findings suggest that Pt@B₁₂N₁₂ functions as a good electrophile and has the capacity for enhanced drug adsorption and sensitivity.