Reprint of “Three-dimensional elemental mapping of phosphorus by quantitative electron spectroscopic tomography (QuEST)” [J. Struct. Biol. 160 (2007) 35–48]

摘要: Abstract We describe the development of quantitative electron spectroscopic tomography (QuEST), which provides 3-D distributions elements on a nanometer scale. Specifically, it is shown that QuEST can be applied to map distribution phosphorus in unstained sections embedded cells. A series 2-D elemental maps derived from images recorded energy filtering transmission microscope for range specimen tilt angles. then reconstructed series. To obtain accurate necessary correct plural inelastic scattering at L 2,3 edge, achieved by acquiring unfiltered and zero-loss each angle. The data are acquired automatically using cross correlation technique drift focus change between successive An algorithm based simultaneous iterative reconstruction (SIRT) implemented information about number atoms associated with voxel volume. assess accuracy determining content ribosomes eukaryotic cell, apply estimate density nucleic acid chromatin cell’s nucleus. From our experimental data, we sensitivity detecting 20 2.7 nm-sized voxel.