Adsorption behavior of metformin drug on the C60 and C48 nanoclusters: a comparative DFT study

Interaction of metformin (MF) drug with C-60, C-48, SiC59, SiC47, GeC59, and GeC47 nanoclusters was investigated using density functional theory to explore a new drug delivery system. All calculations were investigated at the B3PW91 method and 6-311G(d, p) standard basis set in gas and solvent phases. The calculated adsorption energies are about 0.43 and - 2.10 kJ mol(-1) for C-60 and C-48 nanoclusters, respectively. Our results indicated weak adsorption and sensitivity in MF/C-60 and MF/C-48. To make the cluster more appropriate for drug delivery, MF was adsorbed on the SiC59, SiC47, GeC59, and GeC47. Thermodynamic analyses were demonstrated interaction between MF and SiC59, SiC47, GeC59, and GeC47 are exothermic and spontaneous. Although, adsorption energy in SiC59, SiC47, GeC59 and GeC47 indicated strong adsorption, but sensitivity increased only in SiC59 (reduced from 2.17 eV in pure SiC59 to 1.75 eV in MF/SiC59). Furthermore, we predicted a short recovery time for SiC59 nanocluster. It is predicted that MF drug incorporating SiC59 can be extended as a drug delivery system.