Caged Molecules: Principles and Practical Considerations

Joseph P.Y. Kao1

1 University of Maryland Biotechnology Institute, Baltimore, Maryland
Publication Name:  Current Protocols in Neuroscience
Unit Number:  Unit 6.20
DOI:  10.1002/0471142301.ns0620s37
Online Posting Date:  November, 2006
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A caged molecule is an inert but photosensitive molecule that is transformed by photolysis into a biologically active molecule at high speed (typically 1 msec). The process is referred to as photorelease. The spatial resolution of photorelease is limited by the properties of light; submicrometer resolution is potentially achievable. Therefore, focal photorelease of caged molecules enables one to control biological processes with high spatio‚Äźtemporal precision. The principles underlying caged molecules as well as practical considerations for their use are discussed in this unit.

Keywords: caged molecule; caged compound; photolysis; photorelease; uncaging; photostimulation

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Table of Contents

  • What is a Caged Molecule?
  • Why Use Caged Molecules?
  • Common Sense Considerations on the Use of Caged Molecules
  • Handling of Caged Compounds
  • Fundamental Properties of Caged Molecules that Determine Their Performance
  • Comparing the Relative Merits of Different Caged Molecules
  • Analyzing the Rate of Photorelease
  • Diffusion and Spatial Resolution of Photorelease
  • Summary
  • Literature Cited
  • Figures
  • Tables
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Literature Cited

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