Abstract
A phytochemical-loaded nanoparticle is an important therapeutic agent that aids in enhancing the bioavailability of phytochemicals of lower water solubility and delivering the phytochemicals to the site of infection in a targeted manner. This strategy has also been developed for the management of COVID-19. They can be used as antiviral medication carriers, causing the direct death of viral particles and imitating the host in order to neutralize viral processes. In the formulation of phytochemical-loaded nanoparticles against SARS-CoV-2, different categories of nanoparticles, including inorganic, lipid-based, and polymeric nanoparticles, are used. Numerous phytochemicals belonging to the classes of alkaloids, flavonoids, terpenes, terpenoids, saponins, glycosides, polyphenols, and lignans, that demonstrate effective antiviral properties are utilized for the phytochemical-loaded nanoparticles. This approach results in increased solubility and stability of the phytochemicals with lower systemic toxicity, in addition to site-specific delivery. The combination therapy delivers multiple therapeutic agents at the site of infection. It can also be administered directly to the respiratory system by inhalation delivery. Therefore, this approach can potentially inhibit the application of phytochemical-loaded nanoparticles for the treatment of COVID-19, which is still in its replication of the SARS-CoV-2 virus and reduces the severity of the disease. The infancy and a number of obstacles must be overcome prior to their widespread use.