A first-principles study of functionalized clusters and carbon nanotubes or fullerenes with 5-Aminolevulinic acid as vehicles for drug delivery

At present work, we explore the adsorption properties of the 5-Aminolevulinic acid (5ALA) interacting with SWCNTs, C-60, and C-24 by density functional ab initio (DFT) calculations. It was found that the electronic structure of C-60 is more sensitive to the presence of 5ALA in comparison with C-24, (5, 5), and (9, 0) SWCNT. Our results demonstrate that the interactions between 5ALA and the nanostructures are chemisorption. The natural bond orbital (NBO) and density of states (DOSs) analyses represent that the nature of 5ALA adsorption on the applied nanostructures is permanently electrostatic rather than covalent. (C) 2013 Elsevier Ltd. All rights reserved.