Description
This study investigates the effects of cholesterol and microparticles on the structural and mechanical properties of DPPC monolayers, which serve as models for lung surfactants at the air-water interface. Using
compression isotherms, fluorescence imaging, and interfacial rheology, we show that cholesterol incorporation increases the elasticity of DPPC monolayers by inserting its steroid rings between the hydrophobic
tails of the lipids. The addition of microparticles further enhances the elastic modulus at low frequencies, indicating a change in the mechanical properties of the monolayer. These findings offer insight into the role
of both natural and artificial components (e.g. solid micro-pollutants) in modulating the behavior of lung surfactant models and their potential environmental implications.