DFT Study of the Possibility of Delivering Antiviral Drugs Using Chitosan

Drug transport to specific areas of the body is accomplished by drug delivery systems. Components of these systems are often biodegradable and bioabsorbable polymers. The elaboration of effective drug delivery methods can, along with the search for new drugs, significantly enhance the development of corresponding therapeutic strategies. In the present work, the possibility of utilizing chitosan to deliver antiviral drugs is studied using the density functional theory (DFT, B3LYP-D3(BJ)/6-311+G(d,p)). The energies of frontier molecular orbitals and fundamental DFT indices are calculated, densities of electronic states are analyzed. The results indicate that medicinal compounds are adsorbed on chitosan by H-bonds, and the strongest bond energy between chitosan and ivermectin B1b is –34.83 kcal/mol. The analysis of reactivity descriptors for the interaction of chitosan with hydroquinone, chloroquine, and hydroxychloroquine reveals specific interactions indicating that these complexes are not stable. In view of the chitosan compatibility with the human body, its non-toxicity, and the possibility to control the release of medicinal compounds due to such factors as pH, solubility, and ionic strength, we propose to use this compound as a system for the delivery of medicinal compounds.