STUDY OF ADSORPTION PROPERTIES OF ZOLEDRONIC ACID ON THE SURFACE OF CARBON NANOTUBES USING DENSITY FUNCTIONAL THEORY

At present work, we explore the adsorption properties of the Zoldronic acid interacting with carbon nanotubes (CNTs) using density functional theory (DFT). It was found that the electronic strcture of CNT (5, 5) is more sensitive to the presence of Zoledronic acid in comparison with CNT (5, 5) Ga. Our results demonstrate that the interactions between Zoledronic acid and the nanostructures are chemisorptions. The natural bond orbital (NBO) and density of states (DOSs) analyses represent that nature of Zoledronic acid adsorption on the applied nanostructures is permanently electrostatic rather than covalent. The quantum chemical computations were carried out using the hybrid-DFT (Beck 3 parameters plus LYP functional, B3LYP) coupled with the 6-31G* basis set, implemented in the GAMESS program package. Where ECNT(5, 5)-Zoledronic acid and ECNT(5, 5)Ga-Zoledronic acid are the total electronic energies of nanostructures loaded with Zoledronic acid drug after full geometry optimization. ECNT(5, 5) and ECNT(5, 5)Ga are the electronic energies of perfect CNTs without any functional group attached and Zoledronic acid is the electronic energy of Amino acid side chain attached to Zoledronic acid. We investigated the adsorption phenomena of Zoledronic acid on the CNT (5,5) and CNT (5, 5) Ga surfaces using density functional with B3LYP/6-31G* level. Our results show that the chemical adsorption of Zoledronic acid on the CNT (5, 5) system is larger than that on the pristine CNT(5, 5) Ga. our calculations indicate that bond gap Zoledronic acid on the CNT (5, 5) is larger than that on the CNT (5, 5) Ga, so the CNT (5, 5) conductivity is less than that on the CNT (5, 5) Ga, as a result, the CNT (5, 5) is more stable than the CNT (5, 5) Ga.