Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-26T13:51:02.705Z Has data issue: false hasContentIssue false

Low-Loss EELS Spectral Fingerprints of Lipids and Protein

Published online by Cambridge University Press:  02 July 2020

A. Aitouchen
Affiliation:
Stevens Institute of Technology , Hoboken, NJ07030
S. Shi
Affiliation:
Unilever Research , Edgewater, NJ07020
M. Libera
Affiliation:
Stevens Institute of Technology , Hoboken, NJ07030
M. Misra
Affiliation:
Unilever Research , Edgewater, NJ07020
Get access

Extract

Because of their amphiphilic nature, lipids tend to self-assemble into membranes and other topologically complex structures that can serve a number of functions in both natural and synthetic environments. The structure of lipid assemblies often varies on length scales of 2-100 nm, and morphological studies of such structures often require electron-optical methods. Image contrast in an electron microscope is usually generated by large defocus for unstained samples or by positive/negative staining methodologies. We currently are developing alternate approaches to generate image contrast based on spatially resolved Electron Energy Loss Spectroscopy (EELS) [1]. This has allowed us to distinguish between different lipid species as well as between lipids and protein. Low-loss spectra taken from cholesterol, ceramide and protein (BSA) show that these materials have characteristic spectroscopic fingerprints due to both π and σ valence-electron excitations that are sufficiently different to distinguish between them.

Type
Biological Microanalysis
Copyright
Copyright © Microscopy Society of America

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

References:

1.Colliex, C., in : Transmission Electron Energy Loss Spectrometry in Materials Science, Eds. Disko, M.M., Ahn, C.C. and Fultz, B. (TMS, Warrendale, USA, 1992) p. 85.Google Scholar
2.Egerton, R. F., “Electron Energy Loss Spectroscopy in the Electron MicroscopeNew York Plenum (1986).Google Scholar
3.Sun, S.Q., Shi, S-L., Hunt, J. A., and Leapman, R.D.., Journal of Microscopy 177 (1995)18.CrossRefGoogle Scholar
4.Inagaki, T., Hamm, R.N., Arakawa, E.T., and Birkhoff, R.D., Biopolymers 14 (1975) 839847.CrossRefGoogle Scholar
5.Sun, S. Q., Shi, S-L., Hunt, J.A., and Leapman, R. D.Journal of Microscopy 177 (1995) 1830CrossRefGoogle Scholar