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  1. Joined
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    20 Jun '19 15:287 edits
    No light or lenses or anything that vaguely looks like a conventional microscope is used! Instead its just ALL chemistry and chemical analysis with computer processing used!

    https://phys.org/news/2019-06-dna-microscopy-image-cells.html

    "...'DNA microscopy' offers entirely new way to image cells

    Instead of relying on light (or any kind of optics at all), the team uses DNA "bar codes" to help pinpoint molecules' relative positions within a sample.

    ...Until now, microscopy fit into two main categories. The first is based on optics; light microscopy,
    ...The second category is based on dissecting samples at locations defined by a microscope. Computer programs then stitch together each dissected piece into a complete picture of the intact sample.

    ...
    How it [this new method] works;

    First, scientists take cells grown in the lab and fix them into position in a reaction chamber. Then, they add an assortment of DNA bar codes. These stick to RNA molecules, giving each a unique tag. Next, the team uses a chemical reaction to make more and more copies of each tagged molecule—a growing pile that expands out from each molecule's original location.

    "Picture every single molecule as a radio tower broadcasting its own signal outward,"
    ...
    Eventually, the tagged molecules collide with other tagged molecules, forcing them to link together in pairs. Molecules located close to one another will be more likely to collide, generating more DNA pairs. Molecules further apart will generate fewer pairs.

    A DNA-sequencing machine spells out the letters of every molecule within the sample, which takes up to 30 hours. An algorithm the team created then decodes the data—which, in the paper, represents roughly 50 million DNA letters of genetic sequences from each original specimen—and converts the raw data to images.
    ...
    "You're basically able to reconstruct exactly what you see under a light microscope,"
    ..."

    I think that is truly a novel and clever new way to do it.
    I wonder what other truly a novel and clever new ways can be thought up like that to do microscopy?
    Anyone here got an idea on that?
    I have tried to come up with one of my own but so far haven't got far with that although at least I have a few possible embryos of some ideas which I am willing to discuss on request.
  2. Subscribersonhouse
    Fast and Curious
    slatington, pa, usa
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    20 Jun '19 16:15
    @humy
    That last image, is that some kind of microscopic sized animal?
  3. Joined
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    20 Jun '19 16:293 edits
    @sonhouse said
    @humy
    That last image, is that some kind of microscopic sized animal?
    I don't know what that sample is of.
    It says for that image;
    "A visualization of the data for cell populations in a sample, provided by DNA microscopy."
    but I thought the whole point of this new DNA microscopy was for seeing what's going on inside individual cells rather than whole cell populations.
  4. Joined
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    20 Jun '19 17:17
    @sonhouse said
    @humy
    That last image, is that some kind of microscopic sized animal?
    It's a cluster of cells tagged with different molecules.

    Very interesting technology, although it isn't yet at the resolution of a typical light microscope.
  5. Subscribersonhouse
    Fast and Curious
    slatington, pa, usa
    Joined
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    20 Jun '19 21:28
    @wildgrass said
    It's a cluster of cells tagged with different molecules.

    Very interesting technology, although it isn't yet at the resolution of a typical light microscope.
    Maybe not at the best optical scope but the selectivity cannot be matched by any optical tech. Nemarkie, phase contrast, polarization, none of the regular optical tricks can do that bit.
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