Abstract
Electron energy loss spectroscopy (EELS) and energy dispersive X-ray spectroscopy (EDXS) can be used to obtain elemental maps from thin biological samples in the analytical electron microscope. The EELS is particularly sensitive for the low-atomic-number elements, including C, N, and O, as well as other elements with favorable ionization cross-sections, such as Fe. The EDXS is useful for a complementary range of atoms, such as P, S, K, and Ca. A system is described for obtaining elemental distributions in an analytical electron microscope operated in the scanning transmission mode at 100–200 keV beam energy. The spatial resolution is typically limited to 10–20 nm when a conventional source is used. A satellite microcomputer controls acquisition of EELS and EDXS data from successive pixels in an image. These data are processed “on-the-fly” by a host computer to remove the noncharacteristic background intensity. Resulting images are stored on disk and can be analyzed by means of an image display system controlled by interactive software. The technique is demonstrated with elemental maps from two samples: alveolar macrophages containing respirable particles; and pancreatic beta cells that secrete insulin.
Similar content being viewed by others
References
H. Shuman, A. V. Somlyo, and A. P. Somlyo,Ultramicroscopy 1, 317 (1976).
M. S. Isaacson and D. E. Johnson,Ultramicroscopy 1, 33 (1975).
K. E. Gorlen, L. K. Barden, J. S. Del Priore, C. E. Fiori, C. C. Gibson, and R. D. Leapman,Rev. Sci. Instrum. 55, 912 (1984).
R. D. Leapman, C. E. Fiori, K. E. Gorlen, C. C. Gibson, and C. R. Swyt,Ultramicroscopy 12, 281 (1984).
P. Rez and C. Ahn,Ultramicroscopy 8, 341 (1982).
C. Jeanguillaume, M. Tence, P. Trebbia, and C. Colliex,Scan. Electron Microsc. 2, 745 (1983).
D. Kowarski,J. Electron Microsc. Tech. 1, 175 (1984).
P. Statham,Ultramicroscopy 8, 309 (1982).
M. Strahm and J. H. Butler,Rev. Sci. Instrum. 52, 840 (1981).
A. P. Somlyo and H. Shuman,Ultramicroscopy 8, 219 (1982).
T. E. Phillips and A. F. Boyne,J. Electron Microsc. Tech. 1, 9 (1984).
A. V. Somlyo, H. Gonzales-Serratos, H. Shuman, G. McClellan, and A. P. Somlyo,J. Cell Biol. 90, 577 (1981).
C. P. Lechene, J. V. Bonventre, and R. R. Warner, inMicrobeam Analysis in Biology, C. P. Lechene and R. R. Warner, eds., Academic, New York, NY, 1979, p. 409.
R. D. Leapman and R. L. Ornberg, inProc. 41st Annual EMSA Meeting, Phoenix AZ., G. W. Bailey, ed., San Francisco, San Francisco, CA, 1983, p. 590.
C. E. Fiori, C. R. Swyt, and K. E. Gorlen, inMicrobeam Analysis, A. D. Romig and J. I. Goldstein, eds., San Francisco, San Francisco, CA, 1984, p. 179.
A. F. Boyne, R. D. Leapman, R. Wierwille, and R. W. Dudek, inproc. Low Temperature Biological Microscopy Meeting, Cambridge, England, Proc. Roy. Micros. Soc., 1985 (in press).
T. Kitazawa, H. Shuman, and A. P. Somlyo,Ultramicroscopy 11, 251 (1983).
S. B. Andrews, R. D. Leapman, D. Landis, C. E. Fiori, and T. S. Reese,J. Cell. Biol. 99, 424a (1984).
T. A. Hall, inPhysical Techniques in Biochemical Research vol. 1a, G. Oster, ed., Academic, New York, NY, 1971, p. 157.
R. F. Egerton,J. Electron Microsc. Tech. 1, 37 (1984).
H. Shuman,Ultramicroscopy 6, 385 (1981).
M. Shuman and P. Kruit,Rev. Sci. Instrum. 56, 231 (1985).
W. Rom et al. (to be published).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Leapman, R.D., Fiori, C.E. & Gorlen, K.E. Elemental imaging by EELS and EDXS in the analytical electron microscope. Biol Trace Elem Res 13, 89–102 (1987). https://doi.org/10.1007/BF02796624
Issue Date:
DOI: https://doi.org/10.1007/BF02796624