In a simple set-up, the scientists used the translation of position information of fluorescent markers into color information. Overcoming the need for scanning the depth of a sample, they were able to generate the precise 3D information at the same speed as it would take to acquire a 2D image. The general principle of this innovative approach can be used for broader applications and is published online in the PNAS Early Edition this week.
Visualization of Paxillin-fluctuations at the adhesion site of a murine melanoma cell, using the new technique. IMP
Illustration of Paxillin-distribution in a murine melanoma cell using the new technique. Red represents closest and blue furthest distances. IMP
For many disciplines in the natural sciences it is desirable to get highly enlarged, precise pictures of specimens such as cells. Depending on the purpose of an experiment and the preparation of the sample, different microscopy-techniques are used to analyze small structures or objects. However, a drawback of most current approaches is the need to scan the depth of a sample in order to get a 3D picture. Especially for optically sensitive or highly dynamic (fast moving) samples this often represents a serious problem. Katrin Heinze and Kareem Elsayad, lead authors of the PNAS publication, managed to circumvent this difficulty during their work at the IMP.
Precise images of sensitive and dynamic samples
Elsayad, who was part of a research team led by Katrin Heinze at the IMP, used fluorescence microscopy for his experimental set-up. The principle of fluorescence microscopy – now a common tool in biomedical research labs – is as follows: Fluorescent dyes, so-called fluorophores, are turned on by light of a certain wavelength and, as a consequence, “spontaneously” emit light of a different wavelength. Elsayad designed a thin biocompatible nanostructure consisting of a quartz microscope slide with a thin silver film and a dielectric layer. The IMP-scientist then labeled the sample – fixed or live cells – with a fluorescent dye and placed it above the coated slide.
Elsayad explains in simple terms how the biological imaging then took place: “The measured emission spectrum of a fluorescent dye above this substrate depends on its distance from the substrate. In other words, the position information of a collection of fluorophores is translated into color information, and this is what we were measuring in the end”. With this elaborate method, only one measurement is needed to determine the fluorophore distribution above the substrate, with a resolution – in the direction away from the substrate – down to 10 nanometers (1/100.000th of a millimeter). “I believe that the beauty of our method is its simplicity. No elaborate set-up or machines are required to achieve this high resolution. Once the sample is placed on the substrate, which can be mass produced, a confocal microscope with spectral detection is all that is needed”, Heinze points out.
Simple method, big potential
The novel technique was already successfully tested by Elsayad and Heinze. Together with collaborators at the Institute of Molecular Biotechnology (IMBA) of the Austrian Academy of Sciences, they used it to study paxillin, a protein important for cell adhesion, in living cells. The scientists also visualized the 3D dynamics of filopodia, small cell protrusions made of bundled actin-filaments that move very quickly and have a high turnover-rate during cell migration.
Originally developed for a single fluorescent marker, the new method can be adapted for others as well.“There are numerous possibilities for further development and additional applications of the technique”, Elsayad points out. “From optical readout on chips to make faster computers, to more efficient DNA sequencing methods.” The novel technique patented by the IMP has already attracted a lot of interest from several big optical companies.Original publication
Dr. Heidemarie Hurtl | idw
DGIST develops 20 times faster biosensor
24.04.2017 | DGIST (Daegu Gyeongbuk Institute of Science and Technology)
New quantum liquid crystals may play role in future of computers
21.04.2017 | California Institute of Technology
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
24.04.2017 | Physics and Astronomy
24.04.2017 | Materials Sciences
24.04.2017 | Life Sciences