[Frontiers in Bioscience 14, 4337-4347, January 1, 2009]

The electrical surface potential of pulmonary surfactant

Zoya Leonenko1,2, Matthias Amrein3

1Department of Physics and Astronomy, 2Department of Biology, Faculty of Sciences, University of Waterloo, 200 University Avenue, West, Waterloo, N2L 3G1, Ontario, Canada; 3 Department of Cell Biology and Anatomy, Faculty of Medicine, University of Calgary, 3330 Hospital Drive NW, T2N 4N1, Alberta, Canada

TABLE OF CONTENTS

1. Abstract
2. Introduction
2.1. Function and composition of pulmonary surfactant
2.2. Structure of pulmonary surfactant
3. The Electric Surface Potential of Pulmonary Surfactant
3.1. Measuring the electric surface potential
3.2. The average surface potential
3.3. Contrast in surface potential maps
4. The function of the surface potential
5. Summary and Perspective
6. Acknowledgment
7. References

1. ABSTRACT

A molecular film of pulmonary surfactant covers the hydrated lung epithelium to the air. We recently showed that the film exhibits a locally strongly variable electrical surface potential of up to several hundred millivolts. The potential arises from aligned molecular dipoles of the molecules. In the case of the complex structural organization of the phase-separated film of pulmonary surfactant, a map of the local surface potentials allows insight into the local distribution and order of its molecular constituents. Here, we summarize our recent findings and discuss how the electrical surface potential influences the architecture of the film but also changes the way how the lung interacts with the environment.