Single Microbubble Measurements of Lipid Monolayer Viscoelastic Properties for Small-Amplitude Oscillations
Lipid monolayer rheology plays an important role in a variety of interfacial phenomena, the physics of biological membranes, and the dynamic response of acoustic bubbles and drops. We show here measurements of lipid monolayer elasticity and viscosity for very small strains at megahertz frequency. In...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 32(2016), 37 vom: 20. Sept., Seite 9410-7 |
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Weitere Verfasser: | , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2016
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. Lipids |
Zusammenfassung: | Lipid monolayer rheology plays an important role in a variety of interfacial phenomena, the physics of biological membranes, and the dynamic response of acoustic bubbles and drops. We show here measurements of lipid monolayer elasticity and viscosity for very small strains at megahertz frequency. Individual plasmonic microbubbles of 2-6 μm radius were photothermally activated with a short laser pulse, and the subsequent nanometer-scale radial oscillations during ring-down were monitored by optical scatter. This method provided average dynamic response measurements of single microbubbles. Each microbubble was modeled as an underdamped linear oscillator to determine the damping ratio and eigenfrequency, and thus the lipid monolayer viscosity and elasticity. Our nonisothermal measurement technique revealed viscoelastic trends for different lipid shell compositions. We observed a significant increase in surface elasticity with the lipid acyl chain length for 16 to 20 carbons, and this effect was explained by an intermolecular forces model that accounts for the lipid composition, packing, and hydration. The surface viscosity was found to be equivalent for these lipid shells. We also observed an anomalous decrease in elasticity and an increase in viscosity when increasing the acyl chain length from 20 to 22 carbons. These results illustrate the use of a novel nondestructive optical technique to investigate lipid monolayer rheology in new regimes of frequency and strain, possibly elucidating the phase behavior, as well as how the dynamic response of a microbubble can be tuned by the lipid intermolecular forces |
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Beschreibung: | Date Completed 14.06.2018 Date Revised 13.11.2018 published: Print-Electronic Citation Status MEDLINE |
ISSN: | 1520-5827 |
DOI: | 10.1021/acs.langmuir.6b01882 |