Interactions between O2 Nanobubbles and the Pulmonary Surfactant in the Presence of Inhalation Medicines

A dispersion of oxygen nanobubbles (O₂-NBs) is an extraordinary gas–liquid colloidal system where spherical gas elements can be considered oxygen transport agents. Its conversion into inhalation aerosol by atomization with the use of nebulizers, while maintaining the properties of the dispersion, gives new opportunities for its applications and may be attractive as a new concept in treating lung diseases. The screening of O₂-NBs interactions with lung fluids is particularly needed in view of an O₂-NBs application as a promising aerosol drug carrier with the additional function of oxygen supplementation. The aim of the presented studies was to investigate the influence of O₂-NBs dispersion combined with the selected inhalation drugs on the surface properties of two types of pulmonary surfactant models (lipid and lipid–protein model). The characteristics of the air–liquid interface were carried out under breathing-like conditions using two selected tensiometer systems: Langmuir–Wilhelmy trough and the oscillating droplet tensiometer. The results indicate that the presence of NBs has a minor effect on the dynamic characteristics of the air–liquid interface, which is the desired effect in the context of a potential use in inhalation therapies.