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Imaging of Liposomes by Transmission Electron Microscopy

  • Ulrich BaxaEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1682)

Abstract

TEM is an important method for the characterization of size and shape of nanoparticles as it can directly visualize single particles and even their inner architecture. Imaging of metal particles in the electron microscope is quite straightforward due to their high density and stable structure, but the structure of soft material nanoparticles, such as liposomes, needs to be preserved for the electron microscope. The best method to visualize liposomes close to their native structure is cryo-electron microscopy, where thin films of suspensions are plunge frozen to create vitrified ice films that can be imaged directly in the electron microscope under liquid nitrogen temperature. Although subject to artifacts, negative staining TEM can also be a useful method to image liposomes, as it is faster and simpler than cryo-EM, and requires less advanced equipment.

Key words

Liposomes Emulsions Lipids Transmission electron microscopy Negative staining Cryo-electron microscopy 

Notes

Acknowledgment

This project has been funded in whole with Federal funds from the National Cancer Institute, National Institutes of Health, under Contract No. HHSN261200800001E. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the U.S. Government.

References

  1. 1.
    Bibi S, Kaur R, Henriksen-Lacey M, McNeil SE, Wilkhu J, Lattmann E, Christensen D, Mohammed AR, Perrie Y (2011) Microscopy imaging of liposomes: from coverslips to environmental SEM. Int J Pharm 417(1–2):138–150. doi: 10.1016/j.ijpharm.2010.12.021 CrossRefPubMedGoogle Scholar
  2. 2.
    Ruozi B, Belletti D, Tombesi A, Tosi G, Bondioli L, Forni F, Vandelli MA (2011) AFM, ESEM, TEM, and CLSM in liposomal characterization: a comparative study. Int J Nanomedicine 6:557–563. doi: 10.2147/IJN.S14615 CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    Harris JR (2007) Negative staining of thinly spread biological samples. In: Kuo J (ed) Electron microscopy: methods and protocols. Humana Press, Totowa, NJ, pp 107–142. doi: 10.1007/978-1-59745-294-6_7 CrossRefGoogle Scholar
  4. 4.
    Ohi M, Li Y, Cheng Y, Walz T (2004) Negative staining and image classification—powerful tools in modern electron microscopy. Biol Proced Online 6(1):23–34. doi: 10.1251/bpo70 CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Silva MT, Guerra FC, Magalhaes MM (1968) The fixative action of uranyl acetate in electron microscopy. Experientia 24(10):1074CrossRefPubMedGoogle Scholar
  6. 6.
    Zhao F-Q, Craig R (2003) Capturing time-resolved changes in molecular structure by negative staining. J Struct Biol 141(1):43–52. doi: 10.1016/S1047-8477(02)00546-4 CrossRefPubMedGoogle Scholar
  7. 7.
    Cheng Y, Grigorieff N, Penczek PA, Walz T (2015) A primer to single-particle cryo-electron microscopy. Cell 161(3):438–449. doi: 10.1016/j.cell.2015.03.050 CrossRefPubMedPubMedCentralGoogle Scholar
  8. 8.
    Frank J (2002) Single-particle imaging of macromolecules by cryo-electron microscopy. Annu Rev Biophys Biomol Struct 31:303–319. doi: 10.1146/annurev.biophys.31.082901.134202 CrossRefPubMedGoogle Scholar
  9. 9.
    Grassucci RA, Taylor D, Frank J (2008) Visualization of macromolecular complexes using cryo-electron microscopy with FEI Tecnai transmission electron microscopes. Nat Protoc 3(2):330–339. doi: 10.1038/nprot.2007.474 CrossRefPubMedPubMedCentralGoogle Scholar
  10. 10.
    Grassucci RA, Taylor DJ, Frank J (2007) Preparation of macromolecular complexes for cryo-electron microscopy. Nat Protoc 2(12):3239–3246. doi: 10.1038/nprot.2007.452 CrossRefPubMedPubMedCentralGoogle Scholar
  11. 11.
    Milne JL, Borgnia MJ, Bartesaghi A, Tran EE, Earl LA, Schauder DM, Lengyel J, Pierson J, Patwardhan A, Subramaniam S (2013) Cryo-electron microscopy--a primer for the non-microscopist. FEBS J 280(1):28–45. doi: 10.1111/febs.12078 CrossRefPubMedGoogle Scholar
  12. 12.
    Almgren M, Edwards K, Karlsson G (2000) Cryo transmission electron microscopy of liposomes and related structures. Colloids Surf A Physicochem Eng Asp 174(1–2):3–21. doi: 10.1016/S0927-7757(00)00516-1 CrossRefGoogle Scholar
  13. 13.
    Friedrich H, Frederik PM, de With G, Sommerdijk NA (2010) Imaging of self-assembled structures: interpretation of TEM and cryo-TEM images. Angew Chem Int Ed Engl 49(43):7850–7858. doi: 10.1002/anie.201001493 CrossRefPubMedGoogle Scholar
  14. 14.
    Helvig S, Azmi IDM, Moghimi SM, Yaghmur A (2015) Recent advances in Cryo-TEM imaging of soft lipid nanoparticles. AIMS Biophys 2(2):116–130. doi: 10.3934/biophy.2015.2.116 CrossRefGoogle Scholar
  15. 15.
    Kuntsche J, Horst JC, Bunjes H (2011) Cryogenic transmission electron microscopy (cryo-TEM) for studying the morphology of colloidal drug delivery systems. Int J Pharm 417(1-2):120–137. doi: 10.1016/j.ijpharm.2011.02.001 CrossRefPubMedGoogle Scholar
  16. 16.
    Tahara Y, Fujiyoshi Y (1994) A new method to measure bilayer thickness: cryo-electron microscopy of frozen hydrated liposomes and image simulation. Micron 25(2):141–149. doi: 10.1016/0968-4328(94)90039-6 CrossRefPubMedGoogle Scholar
  17. 17.
    Adler K, Schiemann J (1985) Characterization of liposomes by scanning electron microscopy and the freeze-fracture technique. Micron and Microscopica Acta 16(2):109–113. doi: 10.1016/0739-6260(85)90039-5 CrossRefGoogle Scholar
  18. 18.
    Harris JR, Gerber M, Gebauer W, Wernicke W, Markl J (1996) Negative stains containing Trehalose: application to tubular and filamentous structures. Microsc Microanal 2(1):43–52. doi: 10.1017/S1431927696210438 CrossRefGoogle Scholar
  19. 19.
    Aebi U, Pollard TD (1987) A glow discharge unit to render electron microscope grids and other surfaces hydrophilic. J Electron Microsc Tech 7(1):29–33. doi: 10.1002/jemt.1060070104 CrossRefPubMedGoogle Scholar
  20. 20.
    Resch GP, Brandstetter M, Konigsmaier L, Urban E, Pickl-Herk AM (2011) Immersion freezing of suspended particles and cells for cryo-electron microscopy. Cold Spring Harb Protoc 2011(7):803–814. doi: 10.1101/pdb.prot5642 PubMedGoogle Scholar
  21. 21.
    Frederik PM, Hubert DH (2005) Cryoelectron microscopy of liposomes. Methods Enzymol 391:431–448. doi: 10.1016/s0076-6879(05)91024-0 CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media LLC 2018

Authors and Affiliations

  1. 1.Cancer Research Technology Program, Electron Microscopy LaboratoryLeidos Biomedical Research, Inc., Frederick National Laboratory for Cancer ResearchFrederickUSA

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