Take photos at the nanoscale level with a strong and short-wavelength X-ray laser.

For the first time, Lawrence Livermore National Laboratory scientists (LLNL) have demonstrated that people can use extremely short and powerful X-ray pulses to ' capture ' images of objects such as protein before the X-ray destroys the specimen.

At the same time, the team has also set a record for shooting flash images at 25 millionths of a second (femtosecond).

This new method will be suitable for atomic-resolution imaging of biomolecules even if the more powerful X-ray laser technology is currently being built if successful. get this. This technique will allow scientists to gain insight into the areas of material science, plasma physics, biology and medicine.

Photographing single-molecule diffraction using free-electron X-ray laser technology (Photo: Lawrence Livermore National Laboratory).

Using the free electron laser technique at the DESY Institute (Deutsches Elektronen-Synchrotron) in Hamburg (Germany), Livermore scientists in the international cooperation group, led by scientist Henry Chapman from LLNL and Janos Hajdu, a scientist at Uppsala University, was able to obtain a single diffraction pattern of a structured object at the nanoscale before the laser destroyed the object.

Later, a computer algorithm developed by Livermore scientists was used to reconstruct the image of the object , which was based on a previously preserved single diffraction pattern. This ' non-lens ' imaging technique can be applied to atomic imaging because it is not limited by the need to build high-resolution lenses. Flash images can resolve pixels that are 50 nanometers in size, about 10 times smaller than those taken with optical microscopes.

According to the theory, a single diffraction image can be stored from macromolecules, a virus or a cell with extremely bright and extremely short X-ray pulses before the sample is exploded and turned into a plasma. This means that scientists can better understand the protein structure of macromolecules without crystallizing them and thus allowing the study of all proteins quickly.

Computer simulations based on four different models show that it is possible to capture structures near the atomic level by carefully considering the length and strength of the X-ray wavelength pulses before The " stripped " specimen loses electrons and is destroyed. However, until now, there has been no verification by experiment for this technique.

The demonstration by the ' flash diffraction imaging ' experiment uses the world's first soft X-ray technology with free electron lasers (FEL) using the FLASH system at the DESY institute. The FLASH system emits large amounts of soft X-ray pulses by the principle of self-amplifying spontaneous radiation. These pulses are about 10 times brighter than today's brightest X-ray sources, synchrotrons (a molecular accelerator that uses electrons to move close to the speed of light to emit very strong synchrotron light). In addition, this test also demonstrated that it takes only 25 parts per million seconds for the duration of an image capture pulse to occur. The current FLASH is the only free electron laser system in the world that produces radiation in the form of soft X-ray beams. Therefore, it is the first step for future FEL systems capable of emitting even shorter wavelengths of laser beams.

There was a problem as to whether the radioactive sample obtained in such conditions could be recreated to obtain information about the non-destructive specimen.

'These results can become a standardized method,' Chapman said. 'This imaging technique can be applied at the cellular level, below the cellular level and down to the single molecule level.'

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According to Lawrence Livermore National Laboratory, Dong Nai Department of Science and Technology