Free Access
Microsc. Microanal. Microstruct.
Volume 6, Number 5-6, October / December 1995
Page(s) 659 - 664
Microsc. Microanal. Microstruct. 6, 659-664 (1995)
DOI: 10.1051/mmm:1995155

Resolution Limits in the Study of Cardiolipin Crystals by TEM, SAED and AFM

Giovanni Valdrè1, 2, Umberto Muscatello3 et Ugo Valdrè2

1  Department of Mineralogical Sciences, University of Bologna, Piazza di Porta S. Donato 1, 40126 Bologna, Italy
2  Department of Physics, University of Bologna and INFM-CNR, via Irnerio 46, 40126 Bologna, Italy
3  Department of Biomedical Sciences, University of Modena, via Campi 287, 41100 Modena, Italy

Aggregates of cardiolipin molecules have been studied by transmission electron microscopy (TEM), selected area electron diffraction (SAED) and atomic force microscopy (AFM). It is found that cardiolipin molecules are very susceptible to electron damage; the lethal dose being of 80 $\rm el\cdot nm^{-2}$. The finest organized structures revealed by TEM after image recording with the minimum dose technique are rather coarse, about 1 nm, whereas SAED reveals the presence of periodicities down to 0.2 nm, in accordance to the images obtained by AFM, whose application has enabled us to reveal substructures of a size of about 0.2 nm.

8715M - Interactions with radiations at the biomolecular level.
6180F - Electron and positron effects.

Key words
atomic force microscopy -- biomolecular effects of radiation -- electron beam effects -- electron diffraction -- organic compounds -- transmission electron microscopy -- resolution limits -- cardiolipin crystals -- TEM -- SAED -- AFM -- aggregates -- transmission electron microscopy -- selected area electron diffraction -- atomic force microscopy -- electron damage -- lethal dose -- image recording -- minimum dose technique -- periodicities -- substructures -- 0.2 nm

© EDP Sciences 1995