Developed a microscope that provides a three-dimensional (3D), instant intact cells without the need to fix them chemically, or even cut stained.

German and U.S. scientists have done what seemed impossible: they have developed a microscope that provides an advanced three-dimensional (3D), instant intact cells without the need to chemically attach, cut or even stained to study them. Presented in the journal Nature Methods, the new device could fill a gap in current technologies and prove useful in medical sciences and also in structural biology.

Scientists at the Institute for the soft matter and functional materials at the Helmholtz Zentrum Berlin (HZB) in Germany and the United States National Cancer Institute have studied in their natural whole cells frozen quickly.

According to the researchers, high-resolution 3D images of the entire cell are produced in one step. This new device is better than electron microscopy, since, for example, generate 3D images of the cells when they are intact. In addition, it is faster than electron microscopy, with which a researcher can take up to weeks to produce a 3D image of a single cell. The new microscope overcomes the fluorescence microscopy, which allows researchers to see only labeled structures after they are colored.

Taking advantage of the natural contrast between the organic material and water, they said, the team was able to form an image of all cellular structures.

The researchers reconstructed Adenocarcinoma cells of mice in three dimensions. They were even able to see fine details of cells, including nuclear pores nell’involucro nuclear double membrane of the cell nucleus, the invaginations of the inner mitochondrial membrane, the channels of the membrane to the nucleus and the inclusions in the organelles phones such as lysosomes.

The X-ray images have created the ultrastructure of the cells up to 30 nanometers (10 nanometers is approximately equivalent to one ten-thousandth the width of a human hair). The ultrastructure is the detailed structure of a biological sample that is not visible with an optical microscope.

The team used a partially coherent light to illuminate the tiny structures of the object and frozen hydrated and get the high resolution 3D. To produce the light source was used synchrotron dell’HZB, called BESSY II. The researchers explained that the partial coherence is the property of two waves whose relative phase undergoes random fluctuations that are not sufficient to generate a wave is completely incoherent. Using this approach combined with high resolution lenses, they were able to see the ultrastructure of the cells with an excellent contrast.

“We have built a microscope in transmission soft X-ray that takes advantage of the improvements of nanofabrication techniques, which produce X-ray targets with higher resolutions and extreme zones with widths of minors,” the authors wrote in the study.

“We have combined this high resolution lens with partially coherent illumination of the sample instead of low-resolution lens and the illumination semi-incoherent used in previous projects. Even if the partial coherence decreases the maximum resolution possible, given the inconsistency, it provides a much greater contrast between the medium spatial frequencies and higher ones. Therefore, the combination of partial coherence with a goal with better resolution would produce a higher contrast for small features. ‘

According to the researchers, these latest developments in the world of medicine will provide key information on intracellular processes, that is how the virus or nanoparticles penetrate cells or the nucleus. And from a general standpoint, they offer a new tool for structural biology to increase understanding of the structure of the cell.