Electronic structure analysis of bimolecular formation of favipiravir (Fav) and a representative model of boron-nitrogen-carbon (BNC) cage was performed in this work for providing more insightful information regarding the drug delivery purposes by the importance of Fav drug for medication of COVID-19. To achieve the purpose of this work, density functional theory (DFT) calculations were carried out to obtain the stabilized structures and corresponding molecular and atomic scale descriptors. Six models of BNC-Fav complexes were obtained reading the participation of different atomic positions of Fav to interactions with the BNC cage surface. The results yielded BNC-Fav2 at the highest strength and BNC-Fav4 at the lowest strength of bimolecular formations. Molecular orbital–related features and atomic scale quadrupole coping constants all revealed that BNC-Fav2 complex could be proposed for employing in drug delivery process by managing the loaded Fav contribution to future interactions.

An idea of employing an iron-assisted carbon (FeC) monolayer for delivery of 2-thiouracil (2TU) was examined in this work by analyzing structural features for singular and bimolecular models. Density functional theory (DFT) calculations were performed for optimizing the structures and evaluating molecular and atomic descriptors for analyzing the models systems. Two bimolecular models were obtained assigning by S-FeC and O-FeC models, in which each of S and O atom of 2TU was relaxed towards the Fe region of FeC surface in the mentioned models, respectively. The results indicated that both models were achievable with slightly more favorability for formation of S-FeC model. The obtained molecular orbital properties revealed the dominant role of FeC monolayer for managing future interactions of attached 2TU, which is indeed a major role for employing nanomaterials for targeted drug delivery purposes. In addition to energies and molecular orbital features, atomic quadrupole coupling constants indicated the benefit of employing FeC monolayer for drug delivery of 2TU.