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Updated: Jan 27, 2026

Measuring Spatially- and Directionally-varying Light Scattering from Biological Material
Published on: May 20, 2013
Spatially Resolved Membrane Transport in a Single Cell Imaged by Second Harmonic Light Scattering
Mohammad Sharifian Gh1, Michael J Wilhelm1, Michael Moore2
1Department of Chemistry , Temple University , 1901 N. 13th Street , Philadelphia , Pennsylvania 19122 , United States.
Abstract:
We demonstrate that time-resolved second harmonic (SH) light scattering, when applied as an imaging modality, can be used to spatially resolve the adsorption and transport rates of molecules diffusing across the membrane in a living cell. As a representative example, we measure the passive transport of the amphiphilic ion, malachite green, across the plasma membrane in living human dermal fibroblast cells. Analysis of the time-resolved SH images reveals that membrane regions, which appear to be enduring higher stress, exhibit slower transport rates. It is proposed that this stress-transport relation may be a result of local enrichment of membrane rigidifiers as part of a response to maintain membrane integrity under strain.
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