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Holographic Laser Tweezers To Manipulate Cells

Posted by timothy on from the to-fit-on-the-head-of-mutant-minnows dept.

SteamyMobile writes "How do you move things as small as single cells? Using tweezers, of course, but not just any tweezers. These tweezers must be holographic laser tweezers, developed at the University of Glasgow and Oxford University. These tweezers use a hologram to structure a light source in such a way as to exert just enough gentle pressure to move a cell. First, they use light to move water, and now this. I can think of some applications, too."

22 comments

  1. EMH in the future? by darkjedi521 · · Score: 1

    Please state the nature of your medical emergency. :)

    1. Re:EMH in the future? by Anonymous Coward · · Score: 0

      I for one welcome our new holographic tweezer overlords.

    2. Re:EMH in the future? by PHPhD2B · · Score: 1
      Please state the nature of your medical emergency. :)

      "I have a huge crack in my butt" :)

      --
      --I am Sun Tzu of the Borg. Resistance is feudal.
  2. The paper. by jabberjaw · · Score: 4, Informative

    The paper can be found at Optics Express. One can also find video of the tweezers in action.

  3. And the website. by jabberjaw · · Score: 4, Informative

    Further digging led me to theUniversity of Glasgow's Optics Groupd where there is a great deal of information on their project page about optical tweezers. As an aside, I don't suppose anyone has the time to elaborate on the Gerchberg-Saxton algorithm?

  4. pedantic comment by Anonymous Coward · · Score: 0

    Typo in the article title ;)

  5. seen that, done that. by rohan_leader · · Score: 1

    bah, The Doctor from Star Trek:Voyager has been able to do that since he was first conceived in 1995.

    And he can, not only maniuplate [sic] "cells", but also... uh... real things! I don't see laser holographic tweezers doing that anytime soon...

    1. Re:seen that, done that. by Anonymous Coward · · Score: 0

      cells are real dumbass

  6. Optical tweezers arrived in the 80's by juggledean · · Score: 5, Interesting
    What's new in todays article is the holographic part, to be able to have multiple tweezers. The classical optical tweezer was/is done with a lens. It turns out that an intense tightly focused light beam can hold a small bit of dielectric, a small plastic bead or a bacteria or other cell.


    The neater optical tweezer work (IMHO) has been done by attaching a protein molecule to a plastic bead and measure the force generated when that molecule interacts with another molecule. One can measure the force that a single myosin molecule exerts as it pulls on an actin chain and the size of the step that it makes or the force that is exerted on a DNA molecule as it is pulled through the duplicating process.

    1. Re:Optical tweezers arrived in the 80's by the+gnat · · Score: 2, Informative

      Other experiments have included using the tweezers to pull a protein or DNA molecule apart and observe how it folds back up. This can be applied to study the kinetics of protein folding, and also elucidate the mechanisms of protein machinery such as chromatin organizing complexes.

      There's actually quite a bit of work being done with single-molecule studies, and laser tweezers are just one of several methods. One paper I read involved watching a single DNA helicase unwind a fluorescently labelled DNA molecule: the researchers watched the end of the DNA helix fray open as the helicase moved down it.

      The coolest of these experiments in my opinion, though, is this one and a number of followups. These are probably among the most awesome accomplishments in biology in the past decade.

  7. I can see the cheap magazine ads now... by JavaRob · · Score: 2, Funny

    NEW Laser Tweezers! Remove unwanted, excessive facial hair... permanently! Recommended by a number* of well-known physicians!

    (* number may be any integer)

    Oh, wait -- manipulating _cells_.
    Yeah, I guess that's also useful to humanity... but not as exciting.

  8. This is old school by Deanasc · · Score: 1

    I'm not sure how novel and ground breaking this is. The technology has been around for a while, in fact is a simple 'bolt on' option for almost all the leading microscopes brands.

    --
    I've hit Karma 50 and gotten a Score:5, Troll... I win!
  9. And people were getting mad at me about nanotech by Marxist+Hacker+42 · · Score: 1

    First magnets, now light. Next up- Moore's law provides us with an Avagadro processor that can actually use magnets and light to assemble immitation beefsteak at a whole gram a month....

    --
    SJW: a person who perceives an injustice, and while correcting it, commits a greater injustice.
  10. I am not a dr by Anonymous Coward · · Score: 0

    But i guess this can be THE cure to cancer.

  11. Finally! by Ankle · · Score: 1

    A method for Darl McBride to reach his own penis.

  12. Is this new? by biglig2 · · Score: 1

    I'm not a photonic engineer, although I play one on television, but haven't they been using this sort of tool for a very long time? 1 quick google shows researchers at kyoto university doing this in April 2002.

    --
    ~~~~~ BigLig2? You mean there's another one of me?
    1. Re:Is this new? by jabberjaw · · Score: 1

      Holographic optical tweezers have been around for a bit, however this is the first time that I have seen it done in 3-dimensions. That being said, I am only a second year physics undergrad so it very well may have been done before, yet this is the first I have heard of it.

    2. Re:Is this new? by doru · · Score: 1

      You can check the page of David Grier at New York University on this topic.

  13. Another tool in the toolbox by Omniscient+Ferret · · Score: 1

    I'm surprised that no one else has even mentioned the venerable sonic screwdriver yet...

  14. Not as cool as it gets by Wolf1316 · · Score: 2, Interesting

    Though I didn't RTFA, I can tell you there seem to be cooler laser-tweezer applications out there. For instance, right now my sister is working at the Stanford Block Lab, where they are manipulating and studying single molecules with laser traps.

    It's really cool to watch, and manipulating things like RNA Polymerase on a single-molecular scale just seems like the way bio research should be done.

  15. Where are my zircon-encrusted tweezers? by Mal-2 · · Score: 1

    How am I supposed to tend to my dental floss bushes while riding my pygmy pony... with a LASER?

    Mal-2

    --
    How is the Riemann zeta function like Trump rallies? Both have an endless number of trivial zeros.
  16. Gerchberg-Saxton... by doru · · Score: 1
    ...is a phase-retrieval algorithm. If you want to project a pattern with a certain intensity distribution in a certain plane in your medium, |F(x,y)|^2, the initial beam must have a definite intensity and phase in each point of the initial plane.

    The intensity is usually the Gaussian profile of a laser beam, say I(x,y) so you need to compute the initial phase p(x,y). Once you got it, you modulate the laser beam using a nifty spatial light modulator. You're done.

    The algorithm is an iterative one, where you start with an arbitrary phase distribution p0(x,y), get the tentative -complex- distribution in the final plane F0(x,y) by propagation (Fourier transform); of course, its intensity |F0(x,y)|^2 will be nothing like what you wanted, namely |F(x,y)|^2. So what you do is replace its amplitude by the correct one |F(x,y)|, and keep the phase.

    Now you back-transform to the initial plane, where you'll have a new phase p1(x,y), but also a new intensity I'(x,y), that you replace by the "true" one, I(x,y), while keeping the phase, p1(x,y). You keep iterating the algorithm and it converges fairly fast.