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Spot Variation Fluorescence Correlation Spectroscopy for Analysis of Molecular Diffusion at the Plasma Membrane of Living Cells

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Observational evidence for a possible new diffusion path.

B R Hacker, J M Christie

Science (New York, N.Y.)

|January 4, 1991

Summary

New research reveals submicroscopic intracrystalline tubes as a novel diffusion pathway in deformed amphibolite. These novel pathways, observed via transmission electron microscopy, facilitate faster material transport than previously known geological processes.

Area of Science:

Geology
Materials Science
Geochemistry

Background:

Submicroscopic intracrystalline tubes have not been previously recognized as diffusion pathways.
Linear defects in minerals can exhibit unusual contrast and behavior under electron irradiation.

Purpose of the Study:

To investigate the nature of linear defects in experimentally deformed amphibolite.
To determine if these defects represent a new type of diffusion pathway.

Main Methods:

Transmission electron microscopy (TEM) was used to examine experimentally deformed amphibolite.
Minerals like plagioclase and amphibole were analyzed for linear defects and their behavior under electron irradiation.

Main Results:

Deformed plagioclase and amphibole crystals showed linear defects resembling unit dislocations with unusual contrast.

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Last Updated: Jul 12, 2026

Spot Variation Fluorescence Correlation Spectroscopy for Analysis of Molecular Diffusion at the Plasma Membrane of Living Cells

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Electron irradiation caused these defects to expand into well-defined, glassy tubes approximately 20 nanometers in diameter.

These tubes appear to have been filled with silicate-water fluid during experiments.

Conclusions:

Submicroscopic intracrystalline tubes around linear defects are a previously unrecognized diffusion pathway.
Transport through these tubes is potentially orders of magnitude faster than traditional diffusion mechanisms.
This finding has significant implications for understanding material transport in geological settings.