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nanotimes News in Brief

11-01 :: December 2010 / January 2011

This is the first time the so-called ultrastructure of cells has been imaged with x-rays to such precision, down to 30nm.

lens, the researchers were able to visualize the ultrastructures of cells at hitherto unattained contrast.

The new X-ray microscope also allows for more space around the sample, which leads to a better spatial view. This space has always been greatly limited by the setup for the sample illumination. The required monochromatic X-ray light was cre- ated using a radial grid and then, from this light, a diaphragm would select the desired range of wave- lengths. The diaphragm had to be placed so close to the sample that there was almost no space to turn the sample around. The researchers modified this se- tup: Monochromatic light is collected by a new type of condenser which directly illuminates the object, and the diaphragm is no longer needed. This allows the sample to be turned by up to 158 degrees and observed in three dimensions.

These developments provide a new tool in structu- ral biology for the better understanding of the cell structure.

This image shows the researchers at the X-ray microscope. It is located at BESSY II electron storage ring of the Helm- holtz Centre Berlin HZB (left: Gerd Schneider, physicist and team leader of the group X-ray microscopy; right: Peter Guttmann, physicist, scientist in the group X-ray microscopy). © HZB / Rouvière

Gerd Schneider, Peter Guttmann, Stefan Heim, Stefan Rehbein, Florian Mueller, Kunio Nagashima, J Bernard Heymann, Waltraud G Müller & James G McNally: Three- dimensional cellular ultrastructure resolved by X-ray micro- scopy, In: Nature Methods, Volume 7(2010), No 12, De- cember 2010, Pages 985-987, DOI:10.1038/nmeth.1533: http://dx.doi.org/10.1038/nmeth.1533