Photo: REUTERS 2014
Nobel Laureates have made a breakthrough in the technology of microscopic studies, surpassing the boundaries of traditional optical microscopy. In 1873, the German physicist Ernst Abbe formulated a natural limit to the resolution of the microscope due to the wave nature of light. This limit is equal to about half the wavelength of light, or 0.2 micrometer (200 nanometers). For most of the XX century, scientists were convinced that he would never be able to observe an optical microscope objects smaller than 0.2 microns, such as individual molecules in the composition of the cell. However, in the 1930s were designed electron microscopes, the resolution of which is a thousand times greater than that of the traditional light microscope. But for microbiologists they were of little use: high-energy electron beam kills all living things.
Bettsig, Kjell and Merner not shaken formula diffraction limit, but figured out how to work around it. In this future laureates helped fluorescent (“glowing”) molecules, or fluorophores. German Stefan Kjell, 1990 looking for a way to overcome the limitation of Abbe developed the so-called method of suppression of stimulated emission (STED). In 1994, he published an article outlining the method: it is necessary to first use a laser pulse, activating molecules glow, and then – blanking pulse ring-shaped, the ability to “cut” the fluorescent area smaller than the notorious diffraction barrier (see. Wallpapers). But to realize their ideas in practice Helle was only a few years. In 2000, while working at the Institute for Biophysical Chemistry in Göttingen Max Planck, where he moved from the University of Turku, Kjell managed to get the image the bacteria E.coli (Escherichia coli) in the first resolution unattainable.
The other laureates – Americans Eric Bettsig and William Merner – independently created another method of modern microscopy – single-molecule microscopy. Merner in 1989 became the world’s first scientist who managed to zadetektirovat single fluorescent molecule. During this time he worked at the IBM Research Center in San Jose. Eight years later, Merner, who joined the University of California in San Diego, took another important step on the way to the Nobel Prize. He worked on the so-called green fluorescent protein (GFP), the discovery and study of which has already been awarded the Nobel Prize in 2008 (one of the three winners then became a colleague at the university Merner San Diego Roger Tsin). Merner discovered that one of the variants of GFP glow can “turn on” and “off” at the behest of the researcher. To do this it was necessary to act on the protein by electromagnetic waves of a certain length. Scientists have managed to dispel these molecules so that the distance between them is greater than 0.2 m, it is the ordinary light microscope could distinguish between them and “see” through fluorescence.
Bettsig as Kjell, was obsessed with the idea of overcoming barrier diffractive optical microscopy. In the early 90s he had unsuccessfully experimented with so-called near-field microscope in the laboratory of Bell (Bell Labs) in New Jersey. In 1995, he published in the journal Optics Letter theoretical principles, as one would circumvent the diffraction barrier by manipulating the molecules of different colors under the microscope and the imposition of the corresponding images on top of each other. But then Bettsig almost ten years dropped out of academic life and returned to active research only in the 2000s when he found the work on fluorescent proteins glow which can be controlled (as in the experiments Merner). In 2006 Bettsig together with a group of colleagues used a scattered group of individual molecules, the distance between which exceed the Abbe (it allowed them to precisely localize), and by combining a large number of images has made the image of the membrane lysosomes ultrahigh resolution. Relevant article, stating this result was published in the journal Science in 2006.
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