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Updated: May 10, 2026
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Models and Methods to Evaluate Transport of Drug Delivery Systems Across Cellular Barriers
Published on: October 17, 2013
Visualizing molecular diffusion through passive permeability barriers in cells: conventional and novel approaches
Yu-Chun Lin1, Siew Cheng Phua, Benjamin Lin
1Department of Cell Biology, Center for Cell Dynamics, School of Medicine, Johns Hopkins University, United States. ylin54@jhmi.edu
Current Opinion in Chemical Biology
|June 5, 2013
Summary
Cellular diffusion barriers control molecular movement, influencing cell function. This review covers passive permeability barriers in mammalian cells and new probing techniques.
Area of Science:
- Cell Biology
- Biophysics
Background:
- Diffusion barriers are crucial for cellular organization and function.
- Spatiotemporal dynamics of signaling molecules are influenced by these barriers.
- Passive permeability barriers exist in various subcellular locations.
Purpose of the Study:
- To review current knowledge on passive permeability barriers in mammalian cells.
- To describe conventional and novel techniques for probing these barriers.
Main Methods:
- Literature review of existing research on passive permeability barriers.
- Description of established analytical techniques.
- Introduction of a new approach: chemically inducible diffusion trap (CIDT).
Main Results:
- Mammalian cells possess diverse passive permeability barriers.
- Conventional techniques have limitations in characterizing these barriers.
- CIDT offers a new method for probing permeable barriers.
Conclusions:
- Understanding passive permeability barriers is key to cellular physiology.
- Advanced techniques like CIDT are needed for precise barrier characterization.
- This review synthesizes current knowledge and highlights future directions.
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