Cycloaddition [2+2] interaction of some Corticosteroid drugs with C60 nano fullerene: A theoretical study

In this work, the quantum mechanics calculations were carried out to elucidate the adsorption behavior of some corticosteroid drugs (clobetasol, beclometasone, prednisolone, and methylprednisolone) on the surface of C60 nanofullerene using density functional theory (DFT) at B3LYP/631G (d,p) level. After optimization of the structures, various parameters such as HOMO and LUMO energies, energy gap, adsorption energy, cohesive energy, chemical hardness, chemical potential, dipole moment, electrophilicity index and changes in the length of some bonds data were calculated. The results showed that the amounts of energy gap and chemical hardness are decreased with binding of corticosteroids to fullerene, while those of chemical potential and electrophilicity index are increased. It means that nanocarrier increases the drug reactivity. Also, binding and stabilization energies are increased. The C60-Clobetasol, C60-Beclometasone, C60-Prednisolone and C60-Methylprednisolone presented the adsorption energy with the values of 54.3478, -6.5263, 45.1586, and 947.8854 KJ in gas phase, respectively. Moreover, the solubility of nanocarrier has increased in the water solvent compared to the gas phase. These results can be considered in pharmacy for these types of drugs and similar systems. The presence of oxygen atoms in the structure of drugs increases the ability of nanofullerene as a drug carrier, because the ability of nitrogen atoms to protonation in acidic environment weakens their binding to fullerene in the target cell.