Permeation of Nanoparticles into Pulmonary Surfactant Monolayer: In Situ X-ray Standing Wave Studies.

High-resolution X-ray techniques were applied to examine the effects of gold nanoparticles (size <5 nm) on natural pulmonary surfactant and pure DPPC monolayers preliminarily formed on water subphase in a Langmuir trough. Hydrophobic and hydrophilic nanoparticles were delivered from nanoaerosol using electrodeposition method. Grazing incidence diffraction, X-ray reflectivity, and X-ray standing wave measurements allow to monitor the changes in molecular organization of lipid monolayer and to locate the position of gold nanoparticles.