Molecular insights into the encapsulation of fluorouracil molecule inside the single-walled carbon nanotubes

Abstract

Carbon nanotubes (CNTs) have demonstrate potential applications in various molecules' encapsulation due to their nanoscale cylinder structures, used as desirable nanocarriers and nanocontainers for molecular systems. Here, we have studied the incorporation of 5-fluorouracil (5-FU) as an anticancer and provide molecular origin information to develop drug delivery at nanoscale. Quantum mechanics-based calculations showed that armchair CNT (7,7) with a diameter of 9 Å ca. was a favorable nanotube for 5-FU encapsulation. The calculated barrier energy developed based on the NEB technique showed that no barrier activation energy occurs during the incorporation of 5-FU into CNT (7,7). Structural geometries, electronic structure, charge analysis, and molecular properties of more stable complex have been analyzed. This structure of encapsulated drug remained inert, and the interaction nature was typical for the strong physisorption that demonstrating favorable factors for safe drug delivery. The presence of CNTs for the loading of 5-FU facilitates the increased reactivity of fluorouracil reactivity compared to the pristine one. The mechanical properties of the nanotube after drug encapsulation were calculated by Young's modulus and the results showed that the strength of CNTs decreased slightly after the incorporation of 5-FU into the nanotube.