Design of ZnO-Drug Nanocarriers against the Main Protease of SARS-CoV-2 (COVID-19): An In Silico Assay

Abstract

The treatment of coronavirus diseases (COVID-19) is a principal aim worldwide that is required restore public health in the population. To this end, we have been studied several kinds of de novo and repurposed drugs to investigate their ability to inhibit the replication of the virus which causes the current pandemic—the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, finding a vehicle that promotes the controlled dosage is vital for avoiding secondary effects. For this reason, the present work exposes a nanostructured carrier based on ZnO, which is coupled to three repurposed drugs (Chloroquine, Dipyridamole, and Lopinavir) to understand the chemical interaction of the formed composite. The designed composites are modeled and optimized using the DFT formalism. In obtaining exergonic adsorption energies, we found values between 0.582 to 2.084 eV, depending on the used drug. At the same time, the HOMO orbitals demonstrate the electronic overlap between the ZnO-Np and the Lopinavir, which is the molecule with the higher adsorption energy. Finally, we carried out a docking assay to investigate the interaction of free drugs and composites with the main protease of the SARS-CoV-2, finding that the coupling energy of the composites (at around to 0.03 eV) was higher, compared with the free drugs. As such, our results suggest a controlled dosage of the drug on the SARS-CoV-2 target.