Journal of Applied Physiology, Vol 77, Issue 6 2681-2688, Copyright © 1994 by American Physiological Society

ARTICLES

Dynamic surface tension of surfactant TA: experiments and theory

D. R. Otis Jr, E. P. Ingenito, R. D. Kamm and M. Johnson
Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge 02139.

A bubble surfactometer was used to measure the surface tension of an aqueous suspension of surfactant TA as a function of bubble area over a range of cycling rates and surfactant bulk concentrations. Results of the surface tension-interfacial area loops exhibited a rich variety of phenomena, the character of which varied systematically with frequency and bulk concentration. A model was developed to interpret and explain these data and for use in describing the dynamics of surface layers under more general circumstances. Surfactant was modeled as a single component with surface tension taken to depend on only the interfacial surfactant concentration. Two distinct mechanisms were considered for the exchange of surfactant between the bulk phase and interface. The first is described by a simple kinetic relationship for adsorption and desorption that pertains only when the interfacial concentration is below its maximum equilibrium value. The second mechanism is "squeeze-out" by which surfactant molecules are expelled from an interface compressed past a maximum packing state. The model provided good agreement with experimental measurements for cycling rates from 1 to 100 cycles/min and for bulk concentrations between 0.0073 and 7.3 mg/ml.

This article has been cited by other articles:

				F. Lhert, W. Yan, S. C. Biswas, and S. B. Hall Effects of Hydrophobic Surfactant Proteins on Collapse of Pulmonary Surfactant Monolayers Biophys. J., December 15, 2007; 93(12): 4237 - 4243. [Abstract] [Full Text] [PDF]

				S. L. Seurynck, N. J. Brown, C. W. Wu, K. W. Germino, E. K. Kohlmeir, E. P. Ingenito, M. R. Glucksberg, A. E. Barron, and M. Johnson Optical monitoring of bubble size and shape in a pulsating bubble surfactometer J Appl Physiol, August 1, 2005; 99(2): 624 - 633. [Abstract] [Full Text] [PDF]

				S. N. Ghadiali, J. Banks, and J. D. Swarts Effect of surface tension and surfactant administration on Eustachian tube mechanics J Appl Physiol, September 1, 2002; 93(3): 1007 - 1014. [Abstract] [Full Text] [PDF]

				M.J. Morrell, Y. Arabi, B.R. Zahn, K.C. Meyer, J.B. Skatrud, and M. Safwan Badr Effect of surfactant on pharyngeal mechanics in sleeping humans: implications for sleep apnoea Eur. Respir. J., August 1, 2002; 20(2): 451 - 457. [Abstract] [Full Text] [PDF]

				E. P. Ingenito, R. Mora, M. Cullivan, Y. Marzan, K. Haley, L. Mark, and L. A. Sonna Decreased Surfactant Protein-B Expression and Surfactant Dysfunction in a Murine Model of Acute Lung Injury Am. J. Respir. Cell Mol. Biol., July 1, 2001; 25(1): 35 - 44. [Abstract] [Full Text] [PDF]

				W. BERNHARD, J. MOTTAGHIAN, A. GEBERT, G. A. RAU, H. von der HARDT, and C. F. POETS Commercial versus Native Surfactants . Surface Activity, Molecular Components, and the Effect of Calcium Am. J. Respir. Crit. Care Med., October 1, 2000; 162(4): 1524 - 1533. [Abstract] [Full Text] [PDF]

				S. N. Ghadiali and D. P. Gaver III An investigation of pulmonary surfactant physicochemical behavior under airway reopening conditions J Appl Physiol, February 1, 2000; 88(2): 493 - 506. [Abstract] [Full Text] [PDF]

				E. P. Ingenito, L. Mark, J. Morris, F. F. Espinosa, R. D. Kamm, and M. Johnson Biophysical characterization and modeling of lung surfactant components J Appl Physiol, May 1, 1999; 86(5): 1702 - 1714. [Abstract] [Full Text] [PDF]

				F. F. Espinosa and R. D. Kamm Bolus dispersal through the lungs in surfactant replacement therapy J Appl Physiol, January 1, 1999; 86(1): 391 - 410. [Abstract] [Full Text] [PDF]

				H. D. Van Liew and S. Raychaudhuri Stabilized bubbles in the body: pressure-radius relationships and the limits to stabilization J Appl Physiol, June 1, 1997; 82(6): 2045 - 2053. [Abstract] [Full Text] [PDF]