Investigating the performance of BN nanotubes as drug delivery systems for Azacitidine and Decitabine anti-cancer drugs: A theoretical study

The tendency of (8,0) boron nitride nanotube (BNNT) for absorption of Azacitidine (Aza) and Decitabine (Dac) anti-cancer drugs was investigated by density functional theory (DFT) in the gas phase and the presence of the water solvent. Interaction energies, structural parameters, topological properties, and RDG (Reduced density gradient) analysis were used to evaluate the strength of interactions in the complexes. The electronic properties of the nanotube were investigated and compared before and after the adsorption process. The quantum molecular descriptors were used to investigate the reactivity of BNNTs to drugs. The results show that the type of interactions (pi-pi stacking and H-bonding) and the stability of the structures depend on the geometry and orientation of drugs on the nanotube surface. Drugs can physically adsorbed on the nanotube. The recovery time for complexes is short, and the adsorption of drugs on the nanotube is reversible. The presence of solvent reduces the drug recovery time. The interactions in Aza/BNNT complexes are stronger than Dac/BNNT complexes, whereas Dac/BNNT complexes have high chemical activity compared to Aza/BNNT complexes and considered as soft systems. The increase of the dipole moment of the complexes compared to monomers indicates that the drugs can quickly move in the biochemical systems. The NBO (Natural bond orbital) analysis performed to evaluate the charge transfer in complexes. The quantum theory of atoms-in-molecules (QTAIM) was used to assess the nature of interactions in the complexes.