In recent years, the development of effective targeted drug delivery systems with carbon-based nanomaterials such as fullerenes and carbon nanotubes have attracted special attention from a large number of scientists. By taking advantage of density functional theory and quantum theory of atoms in molecules, the interactions between silicon decorated fullerene-C60 and single walled carbon nanotubes towards the umifenovir drug which is a broad-spectrum antiviral drug have been investigated. The structural stabilities, reactivity parameters, some important diagnostic vibrational bands, binding energies and frontier molecular orbital evaluations were carried out. It was found that SiC59 more strongly interacts with umifenovir (−43.17 kcal/mol) and its electronic sensitivity is higher than that of the Si@SWCNT system. To gain insights into the potential activity of the compounds against SARS-CoV-2, the drug, SiC59…drug and Si@SWCNT...drug were docked in the binding pockets of two of the virus protein receptors, namely main protease and RNA-dependent RNA polymerase.