X-Ray Imaging Method Boosts Contrast Of Biological Features

A three-dimensional X-ray imaging method can resolve nanometer-sized biological structures that cannot be imaged with adequate contrast by conventional X-ray microscopy techniques, according to a team of researchers based in Germany and Switzerland (Nature 2010, 467, 436). X-ray imaging methods are traditionally based on absorption and attenuation of the X-ray beam by a sample. In contrast, the technique developed by Martin Dierolf and Pierre Thibault of the Technical University of Munich and coworkers relies on the phase of the transmitted light to generate images. The team recorded numerous diffraction patterns from a mouse bone as the X-ray beam was scanned across the sample and then used the data together with tomographic computing methods to produce 3-D images. The results show that the technique can resolve various types of bone structures on the 100-nm scale that are too similar in composition to be distinguished via other methods. Describing the advance as a “disruptive technology” in X-ray microscopy, University of Hamburg physicist Henry N. Chapman says in a commentary about the work that the technique could soon lead to 3-D X-ray imaging that approaches 1-nm resolution.