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PubMed · 8045814

Evaluation of pressure-driven captive bubble surfactometer.

G Putz·J Goerke·S Schürch·J A Clements
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Abstract

We modified the captive bubble surfactometer [S. Schürch et al. J. Appl. Physiol. 67: 2389-2396, 1989] to facilitate the measurement of surface adsorption rates and to simplify its construction. We used a range of standards and monolayers of dipalmitoylphosphatidylcholine to check the calibration of the device against measurements made in a Wilhelmy surface balance and in the captive bubble by using a cathetometer, and we found good agreement. As a further test we measured the surface properties of rabbit lavage lung surfactant (60,000 x average g for 60 min) at 1.0 mg phospholipid/ml. This material adsorbed within 1 s to near-equilibrium surface tension, reached surface tensions of < 5 mN/m on the second compression, and formed very stable films. We conclude that a captive bubble surfactometer can provide accurate information about important surface properties of lung surfactant films.

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1,2-DipalmitoylphosphatidylcholineAdsorptionAnimalsImage Processing, Computer-AssistedIndicators and ReagentsKineticsPressurePulmonary SurfactantsRabbitsSurface TensionTherapeutic IrrigationThermodynamicsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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G Putz, J Goerke, S Schürch, J A Clements. 1994. Evaluation of pressure-driven captive bubble surfactometer.. https://doi.org/10.1152/jappl.1994.76.4.1417

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