EXPLORING THE ADSORPTION POTENTIAL OF CARBON NANOTUBES AS EFFICIENT ADSORBERS FOR DRUG MOLECULES

Abstract

This research observed the interaction between carbon nanotubes (CTs) and ephedrine (EH) molecules through a comprehensive utilization of density functional theory (DFT) and density functional tight-binding (DFTB) calculations applied to both periodic and isolated structures. EH, as a prevalent pharmaceutical pollutant, interacts with CTs and prominent organic nanostructures, prompting a meticulous examination of CTs’ potential as EH adsorbents. Multiple models of CTs were systematically scrutinized to elucidate their interaction with EH in detail. Given the substantial complexity of systems involving 122-187 atoms, the DFTB methodology was used for geometric optimizations. DFT computations were subsequently employed to procure accurate total energies, enabling the precise evaluation of binding energies between EH and nanotubes. The binding energies, ranging from ‒0.46 eV to ‒0.53 eV, confirm significant non-covalent interactions between CTs and EH. The shortest distance between EH and CT in all observed systems involves the hydrogen atom in the vicinity of the oxygen atom which is also crucial for non-covalent interactions. The outcomes underscore the propensity of CTs to adsorb EH molecules with notable binding energies, striking a balance between robust adhesion and facilitation of desorption under plausible experimental conditions. These findings not only shed light on the fundamental mechanisms governing the CT-EH interaction but also offer promising insights for the practical application of CTs in environmental remediation strategies targeting pharmaceutical pollutants.