Lung surfactant-particles at fluid interfaces for toxicity assessments

Lung surfactant is a complex mixture of lipids and proteins which plays a major role in the respiratory cycle. This makes necessary to understand the effects of different external factors or agents, for example, inhaled particles, as a potential source of alteration of the normal physiological response of lung surfactant. However, in most cases, in vivo studies are difficult to perform, and preliminary studies based in model systems are required. Films of lipids or mixtures of lipids and proteins at the water-vapor interface are accounted as one of the most useful methodologies for initial assessments of the potential toxicity of inhaled particles. Thus, the study of the modifications induced by the incorporation of colloidal particles in the interfacial properties of layers mimicking some of the physicochemical features of lung surfactant might provide a first evaluation of the risks and hazards associated with the inhalation of particulate matter. Considering the importance of particles in technology and industry, it is mandatory to develop strategies providing information about toxicological aspects of these widespread materials. This review focuses its interest on the recent advancements on the application of studied bases on monolayers at the fluid interface as preliminary assay for deepening on a complex situation with biological interest.