Credit: AMERICAN PHYSICAL SOCIETY

Phys. Rev. Lett. 103, 198101 (2009); Phys. Rev. Lett. 103, 198102 (2009)

Researchers have taken the first X-ray diffraction images of intact, hydrated cells.

Because of their short wavelengths, X-rays can penetrate deep into specimens and generate high-resolution images, yet it has been difficult to use X-ray diffraction microscopy on intact cells because the radiation damages them. Freeze-drying the cells makes them more stable but they are still damaged after multiple exposures.

Chris Jacobsen at Stony Brook University in New York and his colleagues protected yeast cells (X-ray diffraction micrograph, pictured) from radiation damage by freezing them to below −170 °C. Because the cells were hydrated when frozen, their structures were similar to those of living cells.

Enju Lima and her colleagues at the European Synchrotron Radiation Facility in Grenoble, France, used a similar technique to image bacteria. Both groups were able to image the cells' internal structures at resolutions of less than 50 nanometres.