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Technology Science

Caltech Researchers Weigh Individual Molecules 130

Posted by CowboyNeal from the heavy-lifting dept.
karvind writes "PhysOrg reports that physicists at the California Institute of Technology have created the first nanodevices capable of weighing individual biological molecules. This technology may lead to new forms of molecular identification that are cheaper and faster than existing methods, as well as revolutionary new instruments for proteomics. The Caltech devices are 'nanoelectromechanical resonators' -- essentially tiny tuning forks about a micron in length and a hundred or so nanometers wide that have a very specific frequency at which they vibrate when excited. Slashdot covered earlier the effort by Cornell for measuring attogram objects which also employs NEMS cantilevers."
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Caltech Researchers Weigh Individual Molecules More

Caltech Researchers Weigh Individual Molecules

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  • Finally! (Score:5, Interesting)

    by InternationalCow ( 681980 ) <mauricevansteens ... m ['mac' in gap]> on Friday April 01, 2005 @04:36AM (#12108838) Journal
    Now we can really measure how many angels can fit together on a pinhead! More seriously, this technology opens up interesting possibilities for high-througput easy mutation screening. Base substitutions (mutations) in a given stretch of DNA will obviously alter its weight. In this way you can easily (well, relatively speaking) detect the presence of a mutation, after which you can select the stretch of DNA that the mutation is in for sequence analysis. It'd be an interesting application for us geneticists.
    • Another more practical use for this technology is to screen for mutated proteins already transcribed in cells. Differences in weights of proteins are much easier to detect than differences in weights of DNA molecules simply because amino acids are much larger than nucleotides.
    • I'm still not sure how this would be any more high throughput than RFLP, SSCP, microarray or Taqman assay (or even straight sequencing!) for SNPs/mutation screening.. I mean you'd have the problem of separating out the fragments of DNA first to get exactly the one you wanted in order to weigh it individually, make sure it was completely uncontaminated with protein.. that doesn't appear to me to lend itself to high-throughput techniques.

      There are of course loads of biological uses for this kind of technol

    • Re:Finally! (Score:2, Interesting)

      by tanverenzo ( 849273 )
      If you had RTFA, then you would have found that the machine is not precise enough to measure SNPs (single nucleotide polymorphisms) in DNA--a common cause of or marker for many genetic disorders (sickle cell anemia immediately comes to mind). Indeed, the mutation would have to be extreme (spanning 100s of nucleotides) for there to be an appreciable weight difference. And even if the DNA were that damaged, its corresponding protein would be misshaped enough for scientists to pick up.

    • Medical Use (Score:5, Funny)

      by bobbuck ( 675253 ) on Friday April 01, 2005 @05:09AM (#12108936)
      Doctors and hospitals need this techology right now so they can weigh patients like Calista Flockhart.

    • Re:Finally! (Score:2, Funny)

      by Frankie70 ( 803801 )

      Now we can really measure how many angels can fit together on a pinhead!
      I am a pinhead, you insensitive clod!!!!
    • I'm just trying to figure out if this is one of the April fools jokes.
      • I'm just trying to figure out if this is one of the April fools jokes.

        If you follow the link, you'll find that the original article is dated March 29th.

    • My friend works for that lab at Caltech. I visited the facility last summer. Pretty interesting equipment they have there. Looked like flux capacitors to me. They started a new company, they will pitch their results to the investors and then try to sell it. I don't know if it is an April fool's joke. If it is, it is probably half-true. I know they use a small cantilever that vibrates and depending what molecules attach to it the frequency at which the cantilever will vibrate. The plan was to develop large

  • Cool tech. Some issues (Score:5, Insightful)

    by Dancin_Santa ( 265275 ) <DancinSanta@gmail.com> on Friday April 01, 2005 @04:36AM (#12108844) Journal
    I was under the impression that at the atomic and molecular level there were quantum phenomena that caused particles to gain and lose mass depending on how they are arranged within the atom/molecule. For example, (just making something up) a molecular bond would result in the total mass of a molecule being less than the sum of the masses of its atoms.

    If working with isotopes, it seems feasible to measure the mass of any particular molecule. What were the issues that were blocking this sort of measurement before?

    • Re:Cool tech. Some issues (Score:5, Informative)

      by RWerp ( 798951 ) on Friday April 01, 2005 @04:50AM (#12108883)
      You're right that the bonds make the total mass smaller. But we're talking about stable molecules here, which bonded in one specific way. If their mass were to change, they would have to decay or interact with the environment. If the molecule is stable, it's energy is very well defined. The only limiting factor is the principle of uncertainty, which basically tells here, that the longer you measure the mass, the more precise you are. So the deviation of the measurement may change, but not its expectation value. It would be very interesting, however, if we could apply this -- or other -- technique to measuring masses of unstable molecules and watch how it changes in time.

      • You're right that the bonds make the total mass smaller. But we're talking about stable molecules here, which bonded in one specific way. If their mass were to change, they would have to decay or interact with the environment. If the molecule is stable, it's energy is very well defined. The only limiting factor is the principle of uncertainty, which basically tells here, that the longer you measure the mass, the more precise you are. So the deviation of the measurement may change, but not its expectation va

      • In chemistry, one bond may be construed as "more energetic" than another is simply because the energy aspect is measured as potential, not kinetic (or other) energy. PE has no real invariant mass equivalent.

        Potential energy isn't equivalent to mass. Potential energy is a way of parsing the total system--it's a byproduct of the viewpoint we take in order to have an orderly system. If I take as a system the Earth and a bowling ball, and move the bowling ball from its initial position 10000m further from

    • Since E=mc^2, m=E/c^2 Thus, a chemical bond (a storehouse of potential energy) can contribute to the mass of a molecule. The more "energetic" the bond, the more energy it stores, and hence the more mass it has to contribute to the overall molecule. Since, some bonds (and hence configurations) are more "energetic" than others then different configurations result in different overall masses for the same molecule. However, the contribution of mass is so small (by a factor of 1/c^2), it greatly diminishes (r

    • The mass of the atoms is almost all contained on the nucleus. Also, the mass of the eletrosfere is almost all contained on the inner electrons (except for the lighter elements, that don't have them).

      Also, the mass lose due to the arrangement of the atoms on a molecule is a tinny error when compared to the lose due to the bound between the electrons and the nucleus and the resting mass of the electrons. The last ones are a tinny error when compared to the nuclear particles bound, and the last one is a smal

  • Call me crazy, but has there been a relatively recent boom in nanotechnology? Seems like there's at least 2-3 new breakthroughs each *day* now!

  • weigh station (Score:5, Funny)

    by Lotharjade ( 750874 ) on Friday April 01, 2005 @04:38AM (#12108849) Homepage Journal
    Who will be stuck working the nano-weigh station of the future? Sounds like a crappy job with a Small paycheck.

  • Nickle-and-Dime (Score:5, Funny)

    by Renraku ( 518261 ) on Friday April 01, 2005 @04:38AM (#12108850) Homepage
    In other news, these devices are being utilized in the brand new series of gas pumps designed to pump gas throughout the next century.

    "We're very excited about this new technology." says an anonymous CEO of a Fortune 500 oil company.

    "No longer can the customer get a free $.009 with every purchase. They'll now be billed down to the exact molecule. Its a tough measure, but those freeloaders were really putting a strain on our budgets."
    • I compulsively buy gas in multiples of 10 gallons, so I don't lose out on the $0.001 change per gallon.

      So what if my tank is never full? Why give those companies ANY MORE THAN THEY DESERVE?

      Huh?!
  • Thats funny... doesnt excitement usually occur because of vibrating, not the other way around? And if this is true, could be devise some sort of perpetual excitement/vibration motion device involving women and 'nanoelectromechanical resonators'? Or perhaps a beowulf cluster of the aforementioned.... *consults the man page for 'woman'* This post a product of SlashPost generator v 0.4.1 alpha build 0138 with SlashClicheMod 2.0

  • Resolution (Score:3, Interesting)

    by lachlan76 ( 770870 ) on Friday April 01, 2005 @04:41AM (#12108856)
    In their experiments this represents about thirty xenon atoms-- and it is the typical mass of an individual protein molecule

    If they can resolve down to one protein mass, then wouldn't that imply that at this point they can not find the difference between molecules?

    • Re:Resolution (Score:2, Informative)

      by operon ( 688118 )
      proteins does not have a typical mass. They have a wide range of masses, with molecules having few aminoacids to large and complex quaternary strucutures.

  • Fool me once... (Score:5, Funny)

    by gnovos ( 447128 ) <gnovos@nospAm.chipped.net> on Friday April 01, 2005 @04:52AM (#12108888) Homepage Journal
    Caltech Researchers Weigh Individual Molecules
    Technology
    Science
    Posted by CowboyNeal on Friday April 01, @01:31AM
    from the heavy-lifting dept.

    Ha ha ha! I get it, I get it.
    "nano" machines, "molecules" "Caltech"

    You got me AGAIN! Man, CowboyNeal, you sure pulled the wool over my eyes. Ha ha ha. Whew, that was a good one.

  • April fools....? (Score:2, Funny)

    by red5 ( 51324 )
    Where is the joke? I don't get it.

  • The problem as I see it (Score:4, Funny)

    by minginqunt ( 225413 ) on Friday April 01, 2005 @04:59AM (#12108908) Homepage Journal
    Is that the problem with this picoscillatory nanoids is that their normal modes have a tendency to reverse the polarity of the neutron flux through the quantum mass matrix.

    This has the unfortunate effect that at that point, you have little choice when determining the altoid-dense uberstate discrepancy to assume that the entire universe weighs exactly the same as Cheryl Tweedie from Girls Aloud.

    Hooray for physics.
    • Is that the problem with this picoscillatory nanoids is that their normal modes have a tendency to reverse the polarity of the neutron flux through the quantum mass matrix.

      But if we reroute energy to the interocitor and reconfigure the main deflector to emit bogon radiation it might just work.

  • This will make it easier for the clerk to know how much to charge me for my nanoparts when I check out.
    • my nanoparts

      It's not how big they are, Eclectro: it's what you can do with them.
      That's what women have been telling me, on the third date, for years...
      I wonder why there's never a fourth date?

  • Here we go again....! (Score:4, Insightful)

    by Le_Batleur ( 822375 ) on Friday April 01, 2005 @05:02AM (#12108918)
    You know, I'm not going to believe one darned word posted today on Slashdot. If anybody has any news they want people to believe, post it tomorrow. Imagine what would happen if the BBC or CNN sprinkled six or seven fake stories into their broadcasts like Slashdot do every year....
    • Yeah, imagine what would happen if the BBC posted [bbc.co.uk] a story which was so obviously an April Fool's gag!
    • April fools "news" items are actualy quite good for theaching people to be critical about the things they hear on the media.

    • I saw this elsewhere the other day, and the timestamp on the linked story is 29 March. So I think this one's safe.

    • Frankly, I don't believe much posted on physorg from 1 Jan to 31 Dec. I've seen a few stories there (both in the news section and blog section) that didn't pass the sniff test and weren't confirmed elsewhere. Grain of salt always recommended.
    • How the hell is that insightful? I would hope that slashdotters have enough common sense to be able to figure out a real story from a joke one. (Yes, I'm a rabid optimist. Why do you ask?) Even if the blurb is confusing due to the nature of the strange stories that are sometimes posted, it should become obvious once you actually click the link whether the story is serious or not. Then again, maybe that's too much to hope for.

      --
      Want a free Nintendo DS, GC, PS2, Xbox. [freegamingsystems.com] (you only need 4 referrals)
      Wired art [wired.com]

  • There goes the neigbourhood (Score:3, Funny)

    by tezza ( 539307 ) on Friday April 01, 2005 @05:06AM (#12108926)
    Your Honour,

    The defendant stands charged for posession of with intent to supply, 300 zeptograms of 3,4-methylenedioxymethamphetamine, a Class A prohibited substance under ... [austlii.edu.au]

  • You know, last i checked we allready knew the mass of all the molecules. On top of that, theres what... 1000 of them top (counting ions and the like) doesnt seem all that useful to me.
    • > doesnt seem all that useful to me.

      Two words: Biological Macromolecules.

    • Re:uhh... so what? (Score:4, Informative)

      by FirienFirien ( 857374 ) on Friday April 01, 2005 @05:29AM (#12108997) Homepage
      We know the masses of a lot of the atoms (though there's a lot more than 1000 isotopes). Molecules are a completely different matter; there's an infinite range of possible molecules, because you can put them together in a lot of different ways; chain molecules (like DNA (hey, there's 5 billion different molecules - and that's only counting humans!)) are difficult to untangle and sort out; when you can weigh them, you can use the masses of atoms to try to calculate how many of each atom is in the molecule, and from there you can try and work out which configurations of atoms are possible.

    • Re:uhh... so what? (Score:3, Informative)

      by mamladm ( 867366 )
      As I understand it, one of the more useful applications envisaged for the technique is not to find out what the actual weight of a given molecule is, but to detect the presence of a particular molecule, such as certain proteins which are present in blood in the very early stages of cancer and which are very difficult to detect with today's methods.
    • Last I checked you did't seem to know the difference between an atom and a molecule.

  • Finally (Score:5, Funny)

    by aussie_a ( 778472 ) on Friday April 01, 2005 @05:12AM (#12108948) Journal
    An instrument that can now weigh my penis.

    Wait. Did I say that outloud? I guess I better turn off my spam-blocker.

  • Amazing... (Score:2, Insightful)

    by RobertKozak ( 613503 )
    Its just amazing how colored our perception can be of a story.

    When I first read it I assumed it was an infamous April 1 slashdot story so each comment I read was biased based on that perception.

    I either thought you were an idiot for replying intelligently to this story or that you were extremely witty and sly in your reply and that demonstrated that you got the joke.

    But I did something we rarely do and went to read the story and found it was written 2 days ago.

    I guess the joke is on me....oh

  • Mass spectroscopy (Score:3, Informative)

    by FirienFirien ( 857374 ) on Friday April 01, 2005 @05:24AM (#12108985) Homepage
    This is the next step from a process called mass spectroscopy, where a molecule is given + or - one electron, then fired through a calibrated magnet to hit a target. If the magnet is calibrated so that a single charge on a molecule of weight W deflects by exactly n degrees, then if the molecule weighs W it will hit the target, and you know the mass of your molecule.

    It's more trial-and-error than TFA, but with a sweep across the calibration settings you get lovely graphs showing how much of a mixture is which compound. It's fast (seconds for a full-range mass chart), which I somehow doubt TFA is quite up to yet - maybe for a single molecule, but something in the description rankles of a slow process.

    • Actually it's called mass spectrometry (Score:1, Informative)

      by Anonymous Coward

      This is the next step from a process called mass spectroscopy, where a molecule is given + or - one electron

      A molecule can not be "given" an electron is mass spec. Ions are generated by ejecting an electron or breaking a bond forming a positive species and a negative radical. Only postive species are detected.

      then fired through a calibrated magnet to hit a target.

      What you're describing is a magnetic sector mass spec but there are many other types.

      If the magnet is calibrated so that a single charge

      • A molecule can not be "given" an electron is mass spec. Ions are generated by ejecting an electron or breaking a bond forming a positive species and a negative radical. Only postive species are detected.

        That's not true at all. Ever heard of NEGATIVE ion chemical ionization? I've done this A LOT. This is not that uncommon.

        Indeed, there are plenty of researchers doing negative ion work.

        For the analysis or proteins you generally interested in the molecular ion...examining how the molecule fragments
    • you get lovely graphs showing how much of a mixture is which compound.

      Not quite. Mass spectrometry itself is used for pure compounds.

      The lovely graphs showing the components of mixtures of which you are thinking I believe are chromatograms (a mass spectrometer can be used as a gas or liquid chromatograph detector).

  • Who says Americans don't understand irony? (Score:4, Funny)

    by panurge ( 573432 ) on Friday April 01, 2005 @05:27AM (#12108990)
    Posting an absolutely straight story with accurate detail, but which sounds like it might be a fake...on 1st April.

    That, my friends who use "irony" when you mean "paradox" or just "contradictory" - that is not only real irony, it's inverted irony. Full marks.

  • Inquiring minds want to know!

  • I think it's great... (Score:5, Funny)

    by Godwin O'Hitler ( 205945 ) on Friday April 01, 2005 @05:54AM (#12109041) Journal
    ...that they're naming these new units after stars of the past. After zeptograms we'll no doubt be seeing grouchofarads, chicobytes, and harpohertz.
  • Nitrogen Triiodide: "Does my bum look big in this?"
  • The whole atomic weight thing was just a best guess then? Or have we been able to calcuate atomic weights, but when it comes to molecules, well, thats just too darn complicated?????
    • no they just defined one mole as 12g of carbon 12. So 1 mole of carbon12 (6.023x10^23 particles) has a mass of 12g. Therefore it's said to weigh 10g mol^-1
  • How much the weighing device weighs?
  • But works in a slightly different manner. It's called a Mass Spectrometer

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