Structural property and interaction between single-walled carbon nanotube and doxorubicin using molecular dynamics simulations

Abstract

Molecular dynamics simulations in aqueous solution were carried out to understand molecular properties of the anticancer drug, carried by single-walled carbon nanotube (SWCNT). The doxorubicin drug, DOX, in free form (DOXfree) and its complexes both inside (DOXin-SWCNT) and outside (DOXout-SWCNT) the pristine SWCNT were chosen to be the three modeled studied. It was found, as expected, due to the collaborative interaction with the surface of the tube that the DOX in the DOXin-SWCNT is much less flexible than that of the other two forms. The DOX in both complexes was also observed to form the aromatic stacking interaction with the SWCNT surface. Interestingly, the DOX in the DOXin-SWCNT and DOXout-SWCNT complexes were found to move from one end to the other of the SWCNT, parallel to the tube surface at the distance (from the center of mass of the drug to the tube surface) of 4.5 Å and 4.0 Å, respectively. In addition, simulations were also extended to the DOX, complexed inside the –OH and –COOH functionalized SWCNTs. The results show that no significant difference was found between the structural data obtained from the functionalized SWCNTs (OH-SWCNT and COOH-SWCNT) and those of the pristine SWCNT.