Interfacial Behavior of Lung Surfactant: A Confocal Enabled Langmuir Trough

Lung surfactant (LS) is a complex mixture of lipids and proteins which lines the air-liquid interface in the alveoli and is responsible for modulating surface tension and reducing the work of breathing. Competitive adsorption of contaminant serum protein molecules displaces LS from the interface causing an inability to modulate surface tension. Inactivation of LS by serum proteins can be reversed utilizing a polymer induced depletion attraction to force LS back to the interface. To visualize lung surfactant in vitro, a Langmuir trough was designed and built at UCSB to accommodate the minimal height requirements necessary for confocal imaging. Imaging has confirmed predictions of LS behavior under compression and the stabilizing properties of polyethylene glycol.