An ultra-high-resolution imaging technique using X-ray diffraction is a step closer to fulfilling its promise as a window on nanometer-scale structures in biological samples. In the Proceedings of the National Academy of Sciences, researchers report progress in applying an approach to "lensless" X-ray microscopy that they introduced one year ago. They have produced the first images, using this technique, of biological cells specifically the intriguing polyextremophile Deinococcus radiourans. Better ability to see nanoscale structures in cells could yield important insights for evolutionary biology and biotechnology. In the case of D. radiourans, for example, it could help to settle questions about whether or how the structure of this organism's DNA-bearing nucleoid region accounts for its hardiness against ionizing radiation. Having demonstrated the resolution, reliability, and reproducibility of their technique, the researchers are now working to extend it to three-dimensional imaging of biological cells.
X-ray imaging is best known for its medical applications, such as traditional radiographs and CT scans. Yet the use of X-rays goes far beyond routine imaging. In particular, the very short wavelength of X-ray radiation allows various modes of microscopy that can reach the nanometer resolution. One of the main hurdles to high-resolution X-ray microscopy is the difficulty of producing high-quality X-ray lenses. To overcome these difficulties, so-called "lensless" microscopy methods have emerged in the last decade. A technique developed by researchers now in the biomedical physics group at Technische Universitaet Muenchen (TUM) has shown great promise for ultra-high resolution imaging of materials and life science samples.
This imaging technique, called ptychography, was first introduced in the 1970s for electron diffraction. It consists in measuring full far-field diffraction patterns as a small illumination is scanned on a sample.
|Contact: Andreas Battenberg|
Technische Universitaet Muenchen