Theoretical study of Drug Delivery on Sn (CH3)2(N-acetyl-L-cysteinate) with SWCNT

The interaction of anticancer drug Sn (CH3)2(N-acetyl-L-cysteinate) with carbon nanotube (CNT) is investigated by Quantum chemical ab initio calculations at FIF/ (LanL2DZ+STO-3G) and HF/ (LanL2DZ+6-31G) levels in gas phase and solution. The solvent effect is taken into account via the self-consistent reaction field (SCRF) method. Carbon nanotubes can act as a suitable drug delivery vehicle for internalization, transportation and translocation of Sn (CH3)2(NCA) within biological systems. Thermodynamical analysis indicate that the relative energies (AE), enthalpies (MI) and free Gibbs energies (AG) are negative for Sn (CH3)2(NCA) —CNT system but the calculated entropies (AS) are Positive, suggesting thermodynamic favorability for covalent attachment of Sn (CH3)2(NCA) into carbon nanotube. Also, the results show that with increasing dielectric constant of solvent the stability of Sn (CH3)2(NAC) — CNT complex decreases. Furthermore, anisotropic chemical shift tensor (Acr), total atomic charge and asymmetry parameter (q) have been calculated using the CIAO method, results being compared with CGST data. From the NMR calculations, it can be seen that the NMR (Aa.q) parameters at the sites of nitrogen, oxygen as well as C-2 and C-3 nuclei are significantly influenced by intermolecular hydrogenbonding interactions but the quantity at the site of S-27 is influenced by nonspecific solute-solvent interaction such as polarizability/polarity.