Effect of SP-C on Surface Potential Distribution in Pulmonary Surfactant: Atomic Force Microscopy and Kelvin Probe Force Microscopy Study

TitleEffect of SP-C on Surface Potential Distribution in Pulmonary Surfactant: Atomic Force Microscopy and Kelvin Probe Force Microscopy Study
Publication TypeJournal Article
Year of Publication2009
AuthorsHane, F., B. Moores, M. Amrein, and Z. Leonenko
JournalUltramicroscopy
Volume109
Start Page968
Issue8
Pagination968-973
Date Published07/2009
Keywordsatomic force microscopy, DPPC, eggPG, kelvin probe force microscopy, lipid monolayer, pulmonary surfactant, SP-C
Abstract

The air–lung interface is covered by a molecular film of pulmonary surfactant (PS). The major function of the film is to reduce the surface tension of the lung’s air–liquid interface, providing stability to the alveolar structure and reducing the work of breathing. Earlier we have shown that function of bovine lipid extract surfactant (BLES) is related to the specific molecular architecture of surfactant films. Defined molecular arrangement of the lipids and proteins of the surfactant film also give rise to a local highly variable electrical surface potential of the interface. In this work we investigated a simple model of artificial lung surfactant consisting of DPPC, eggPG, and surfactant protein C (SP-C). Effects of surface compression and the presence of SP-C on the monolayer structure and surface potential distribution were investigated using atomic force microscopy (AFM) and Kelvin probe force microscopy (KPFM). We show that topography and locally variable surface potential of DPPC–eggPG lipid mixture are similar to those of pulmonary surfactant BLES in the presence of SP-C and differ in surface potential when SP-C is absent.

URLhttp://www.sciencedirect.com/science/article/pii/S0304399109000746
DOI10.1016/j.ultramic.2009.03.046
Refereed DesignationRefereed
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