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arXiv · 1011.6081

Sensitive detection of ultra-weak adhesion states of vesicles by interferometric microscopy

Huang Zen-Hong·Gladys Massiera·Laurent Limozin·Paul Boullanger·Valignat Marie-Pierre·Annie Viallat
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Abstract

We have used an original analysis of reflection interference contrast microscopy (RICM) to detect an ultra-weak specific interaction between a glycolipid vesicle and a lectin-coated substrate. The membrane height fluctuations in the contact zone are observed with a high illumination aperture; the membrane profile and the membrane-substrate distance are quantitatively determined using the new analysis, which accounts for multiple interfaces and multiple incidence rays. We showed that this refined version of RICM theory is necessary, specifically in the case of intermediate membranesubstrate distance (30 nm) and helped to discriminate between the ultra-weak interaction and pure gravitational sedimentation

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Huang Zen-Hong, Gladys Massiera, Laurent Limozin, Paul Boullanger, Valignat Marie-Pierre, Annie Viallat. 2010-11-28. Sensitive detection of ultra-weak adhesion states of vesicles by interferometric microscopy. https://doi.org/10.1039/b925373d

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