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Updated: Jan 27, 2026
11:57
Measuring Spatially- and Directionally-varying Light Scattering from Biological Material
Published on: May 20, 2013
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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.
Biochemistry
|March 27, 2019
Summary
Time-resolved second harmonic (SH) light scattering images living cells to map molecular transport across membranes. Stressed membrane areas show slower molecule movement, suggesting a protective response.
Area of Science:
- Cell biology
- Biophysics
- Optical imaging
Background:
- Understanding molecular transport across cell membranes is crucial for cellular function.
- Existing methods often lack spatial resolution or are invasive.
- Cellular membranes undergo mechanical stress, potentially affecting transport.
Purpose of the Study:
- To develop and apply time-resolved second harmonic (SH) light scattering as an imaging technique.
- To spatially resolve molecular adsorption and transport rates across living cell membranes.
- To investigate the relationship between membrane stress and molecular transport rates.
Main Methods:
- Utilized time-resolved second harmonic (SH) light scattering imaging.
- Measured passive transport of malachite green across the plasma membrane.
- Employed living human dermal fibroblast cells.
Main Results:
- Successfully imaged and quantified molecular transport rates in real-time.
- Identified slower transport rates in membrane regions exhibiting higher stress.
- Demonstrated spatial resolution of adsorption and diffusion dynamics.
Conclusions:
- Time-resolved SH light scattering is a viable modality for studying membrane dynamics.
- Membrane stress correlates with reduced molecular transport rates.
- This stress-transport relationship may indicate a cellular mechanism for maintaining membrane integrity.
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