Current study mainly describes the delivery of three model nitrogen mustard drugs with heterocyclic substituents by single-walled carbon nanotube (SWCNT) as a drug delivery system. The electronic prop-erties and interaction energies were calculated using density functional theory (DFT). Results suggest that the model drugs bind exothermically with SWCNT. HOMO-LUMO, DOS plots and non-covalent interaction (NCI) plots indicate that the interaction between the drugs and SWCNT are weak. Further, calculations of quantum mechanical descriptors suggest that electron migration takes place from SWCNT to the drug. Finally, molecular dynamics simulation was performed to investigate the effect of EtOH co-solvent on the stability of the drug-SWCNT complex. The results suggest that the complexes are most stable in a water environment and the addition of EtOH co-solvent makes it unstable. In summary, all the results suggest that SWCNT may successfully deliver the investigated model nitrogen mustard drugs and these systems are most stable in a water solvent. (c) 2021 Elsevier B.V. All rights reserved.