Comprehensive theoretical prediction of the stability and electronic properties of hydroxyurea and carmustine drugs on pristine and Chitosan-functionalized graphitic carbon nitride in vacuum and aqueous environment

Abstract

In this survey, the effectiveness of the carbon nitride in the form of graphitic structure (CN) as a drug delivery system for hydroxyurea (HU) and carmustine (BCN) anticancer drugs was evaluated through density functional theory (DFT) in both aqueous and vacuum phase. Moreover, a type of possible carrier based on functionalization graphitic-carbon nitride with chitosan is established with the goal of improving therapeutic efficacy and boosting designed deliverer for anticancer drugs. To explore the effectiveness of CN and functionalized CN, some important characteristics of HU and BCN drugs, CN carriers, and drug/CN complexes were calculated. Optimized geometries show that the best appropriate site for the adsorption of selected drugs on the nanosheets surface is the parallel orientation. The calculated adsorption energy in all studied complexes is negative, indicating that all of the analyzed structures are reliable and the interaction of the drug molecules with the examined nanosheets is a spontaneous process. Also, it turned out that the adsorption of BCN on the CN and f-CN is greater than HU. In accordance with the findings of the NBO, in the HU/CN and HU/f-CN complexes, the charges transfer positions on the direction of the HU molecule to the nanosheet, while in the BCN/CN and BCN/f-CN structures, charge transfer happens from the nanosheet to the BCN drug. The values of solvation energy exhibited a remarkable enhancement in the stability of f-CN after adsorption of the drug in the presence of water solvent. Functionalized nanosheets have a high sensitivity according to their electrical characteristics, implying their potential for drug release. Thus, HU/f-CN and BCN/f-CN complexes are favorable systems and functionalized nanosheet is a better carrier in comparison to pristine nanosheet for the HU and BCN drug delivery system. Generally, the results imply that g-C3N4 might be utilized as an effective drug-deliverer design for the HU and BCN drugs to treat diverse kinds of cancer.