DFT Simulation of Geometry and Electronic Structure of Fullerenol - Cisplatin Conjugate as Agent of Cancer Therapy

Fully optimized structures of the fullerenol (Fl=C60(OH)24) - cisplatin conjugate (Fl + Cis) were obtained using the DFT simulation. The DFT/B3LYP/SV/Lanl2DZ level of theory has been used. From the results of calculation of the structural parameters, it can be concluded, that the interaction of Fl with Cis in vacuum leads to the increase of the Pt-N bond length compared to the result for Cis and decrease of the Pt-Cl bond length. The solvation effect for the Fl + Cis complex leads to the decrease of the Pt-N bond length compared to the result for vacuum and increase of the Pt-Cl bond length compared to the result for vacuum and increase of the Pt-Cl bond length compared to the result for vacuum. From the results of the calculation of structural parameters for the Fl with Cis conjugate, it can be concluded that the Pt-N bond in the aqueous solution is enhanced while the Pt-Cl bond is weakened, which can affect the biological activity of the Cis in this complex. The influence of the localization of HOMO and LUMO orbitals on the biological activity of the conjugate under consideration was analyzed. The paper presents the results of DFT simulation of the atomic and electronic structure of water-soluble cisplatin conjugate derivatives and nanocarbon structures, such as fullerenol Fl, as well as the results of studying the possible mechanisms of their biological activity.