Biomolecules captured in a flash

(LLNL) scientists for the first time have validated the idea of using extremely short and intense X-ray pulses to capture images of objects such as proteins before the X-rays destroy the sample. At the same time, the team also established a speed record of 25 femtoseconds for flash imaging.

According to LLNL, the new method will be applicable to atomic-resolution imaging of complex biomolecules when even more powerful X-ray lasers, currently under construction, are available. The technique will allow scientists to gain insight into the fields of materials science, plasma physics, biology and medicine.

Using the free-electron laser at Deutsches Elektronen-Synchrotron (DESY) in Hamburg, Livermore scientists, as part of an international collaboration led by LLNL’s Henry Chapman and Janos Hajdu of Uppsala University, were able to record a single diffraction pattern of a nanostructured object before the laser destroyed the sample.

A Livermore-developed computer algorithm was then used to recreate an image of the object based on the recorded diffraction pattern. This “lensless” imaging technique could be applied to atomic-resolution imaging because it is not limited by the need to build a high-resolution lens. The flash images could resolve features 50 nanometres in size, which is about 10 times smaller than what is achievable with an optical microscope.