Unveiling the potential of silicon carbide nanotubes as advanced nanocarriers for anticancer drug delivery: a multiscale computational perspective

This study explores silicon carbide nanotubes (SiCNTs) as delivery vectors for the anticancer drug 5-fluorouracil (5-FU) using density functional theory (DFT) and molecular dynamics (MD) simulations. Adsorption behavior was analyzed for both encapsulated and surface-attached configurations across various zigzag SiCNT diameters using DFT calculations. Results revealed strong binding affinity, stable encapsulation, and significant electronic interactions, with larger diameters enhancing band gap energies (e.g., 1.41 eV for 5-FU/SiCNT (14,0)). Optical analyses demonstrated substantial changes in dielectric function and absorption spectra, with a notable increase in UV (100%) and visible (35%) light absorption, facilitating drug optical detection. MD simulations confirmed rapid spontaneous drug adsorption, consistent with DFT findings. The drug adsorption via van der Waals interactions increases with diameter, consistent with the experimental findings for carbon nanotubes (CNTs). The 5-FU is effectively encapsulated within SiCNTs (≥5 Å) and remains stable (−30 kcal mol −1 ), with SiCNT (10,0) demonstrating the highest efficiency. SiCNT stability in water improved with increasing diameter. 5-FUs align parallel to the surface via π - π interactions and form clusters through hydrogen bonding. The 5-FU adsorbs more efficiently on SiCNT than on pristine CNT, consistent with previous studies for other drugs. These findings highlight SiCNTs as promising vectors for advanced drug delivery systems targeting cancer treatment.