ABSTRACT
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been a major health burden in the world. So far, many strategies have been investigated to control the spread of COVID-19, including social distancing, disinfection protocols, vaccines, and antiviral treatments. Despite the significant achievement, due to the constantly emerging new variants, COVID-19 is still a great challenge to the global healthcare system. It is an urgent demand for the development of new therapeutics and technologies for containing the wild spread of SARS-CoV-2. Inhaled administration is useful for the treatment of lung and respiratory diseases, and enables the drugs to reach the site of action directly with benefits of decreased dose, improved safety, and enhanced patient compliance. Nanotechnology has been extensively applied in the prevention and treatment of COVID-19. In this review, the inhaled nanomedicines and antibodies, as well as intranasal nanodrugs, for the prevention and treatment of COVID-19 are summarized.
ABSTRACT
Efficient mucosal delivery remains a major challenge for the reason of the respiratory tract mucus act as a formidable barrier to nanocarriers by trapping and clearing foreign particulates. The surface property of nanoparticles determines their retention and penetration ability within the respiratory tract mucus. However, the interaction between nanoparticles and mucus, and how these interactions impact distribution has not been extensively investigated. In this study, polymeric nanoparticles loaded with a baicalein-phospholipid complex were modified with two kinds of polymers, mucoadhesive and mucus-penetrative polymer. Systematic investigations on the physicochemical property, mucus penetration, transepithelial transport, and tissue distribution were performed to evaluate the interaction of nanoparticles with the respiratory tract. Both nanoparticles had a similar particle size and good biocompatibility, exhibited a sustained-release profile, but showed a considerable difference in zeta potential. Interestingly, mucus-penetrative nanoparticles exhibited a higher diffusion rate in mucus, deeper penetration across the mucus layer, enhanced cellular uptake, increased drug distribution in airways, and superior local distribution and bioavailability as compared to mucoadhesive nanoparticles. These results indicate the potential of mucus-penetrative nanoparticles in design of a rational delivery system to improve the efficiency of inhaled therapy by promoting mucus penetration and increasing local distribution and bioavailability.