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Recent advances in freeze-fracture electron microscop: the replica immunolabeling technique


Freeze-fracture electron microscopy is a technique for examining the ultrastructure of rapidly frozen biological samples by transmission electron microscopy. Of a range of approaches to freeze-fracture cytochemistry that have been developed and tried the most successful is the technique termed freeze-fracture replica immunogold labeling (FRIL). In this technique samples are frozen fractured and replicated with platinum-carbon as in standard freeze fracture and then carefully treated with sodium dodecylsulphate to remove all the biological material except a fine layer of molecules attached to the replica itself. Immunogold labeling of these molecules permits their distribution to be seen superimposed upon high resolution planar views of membrane structure. Examples of how this technique has contributed to our understanding of lipid droplet biogenesis and function are discussed.


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Correspondence to Horst Robenek.

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Open Access This article is published under license to BioMed Central Ltd. This is an Open Access article is distributed under the terms of the Creative Commons Attribution License ( ), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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Robenek, H., Severs, N.J. Recent advances in freeze-fracture electron microscop: the replica immunolabeling technique. Biol. Proced. Online 10, 9–19 (2008).

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Indexing terms

  • Freeze Fracturing
  • Microscopy, Immunoelectron
  • Immunoǵold Techniques