Major breakthrough: electron microscope to take cell color photos!

Imagine if the world lost color, only the combination of black and white gray, what will the landscape in front of us become? Under the electron microscope, what we can see is such a world.
electron microscope can help us look at tiny viruses and cell microstructits, but it can only get black-and-white grayscale images.
recently, researchers at the University of California, San Diego, developed a new technology that makes it possible to "take color photos with an electric mirror."
they marked the sample with special dyes and got multi-color electro-mirror imaging. The color-colored world of electron mirrors In the past, optical microscopes led people into the unrecoceable microscopic world for the first time, and microorganisms and microstructures in various living organisms began to become known.
However, when people need to look at more tiny structures, the magnification of the optical microscope is not enough: the resolution limit of the optical microscope is about 200 nm, which, even if magnified, cannot be seen clearly.
to further improve the resolution, scientists replaced visible light with much shorter beams of electrons, creating electron microscopes.
electron microscope enables microscopic imaging to distinguish 0.1 nm, an important technology that won the Nobel Prize in Physics in 1986.
, however, the electron microscope has its drawbacks: it's a color-colored black-and-white world.
different colors of visible light, we can also easily dye or fluorescently label specific components of biological tissue.
image obtained by the electron mirror is a "grayscale map" that reflects how much electrons (i.e. brightness) there is no color information.
of course, people can color the electro-mirror image later, but such coloring does not selectively highlight the structure to be observed.
if the grayscaness in the original image doesn't make much difference, it's hard to separate them later.
image of this dreamy phage comes from a transmission electron microscope, and its color is "pseudo-color".
images from: Sterling Publicing Scientists have made a number of efforts, such as adding heavy metals, to improve "contrast" in order to make electric mirror images more "focused."
are mainly made up of lighter elements such as hydrocarbon oxide, and the images that electrons pass through are less contrasting (like a faint pencil drawing).
a more black-and-white image can be obtained if the background is dyed dark with heavy metals such as tyrin, uranium, or lead, or if they are combined with lipids or proteins.
, however, it is still not possible to focus on distinguishing specific biom molecules.
scientists have also tried to bind these heavy metal particles to antibodies, allowing them to bind to specific biomass molecules, but the "label" is difficult to reach cells and therefore has limited scope of application.
of negative dyeing.
"color" black-and-white images, and this time, the researchers have come up with some new ideas for "staining" electro-mirror images.
they connected dye molecules to different molybon metal elements and allowed them to precipitate around specific markers.
although there is still no true color under the electron microscope, these dyes can produce signals that distinguish them from each other by projecting the energy loss of electrons.
this, it is equivalent to adding different color labels to the sample.
the researchers coupled the pigment diaminyl benzene with a tantalum metal as a "special dye" for electron microscopes.
you want to label a biome molecule, you connect the corresponding antibody to a fluorescent group or oxidase molecule, which is then induced by light or enzymes to induce a reaction that allows the dye to be deposited around the target.
"staining" is completed, electro-mirror imaging is performed in accordance with conventional zirconium oxide negative dyeing to enhance contrast.
Ln-DAB2 dyes and dyeing methods: antibody-specific marker target molecules (red for fluorescent molecules, green for spicy root peroxidase) with antibody-specific markers (pictured are red-labeled mitochondrials and green-labeled nucleofilms), respectively, to allow different Ln-DAB2 dyes in-place oxidation precipitation near antibodies.
after routine sample processing and imaging separately, using computer processing to obtain color images.
, the researchers projected a beam of electrons with consistent dynamic energy on the sample.
when electrons pass through a sample, they collide with the atoms in them, losing some of their energy, and where they have been treated with different dyes, the energy loss of electrons can make a significant difference.
by detecting these differences, you can differentiate the staining position from the background.
processed by computer, the corresponding signals of different dyes are converted into different pseudo-colors, and then superimposed with the original black and white electro-mirror pictures, so that we can see the color of the electric mirror at the beginning.
color electron mirror imaging: A is a traditional electroscope, C and D are marked mitochondrial and cell membranes, E is a pseudo-color overlay for half a day, color or "fake"? Indeed, the electron beam still has no real color when it is distinguished by energy differences.
, however, the dye's markings still play a big role compared to the late coloring of pure imagination.
authors have shown that this method can be used for cell and tissue staining, and enough to separate different molecular markers from traditional black-and-white electroscopic imaging.
Applications of colored electron mirrors: star-shaped glial cells share synaptic structure diagrams (F), endosome vesicle maps (H) mediated by cell permeable peptides, and newly synthesized PKM positioning maps (D) in neurons currently only produce three "colors": they are marked red, green, and yellow, respectively.
hope that more colors will be added in the future to further improve the contrast of the images.
over the past two decades, ultra-high-resolution fluorescence microimaging technology has pushed the limits of optical microscopy, and now the world of electron microscopes is becoming more colorful.
advances in these technologies will lead scientists to gain a deeper understanding of the fine structure inside cells and uncover more of the mysteries of life in the microcosm.
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