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Biotech Power Science

Blood Protein Used to Split Water 230

brian0918 writes "The Imperial College in London is reporting that genetically-engineered blood protein can be used to split water into oxygen and hydrogen. The abstract can be viewed for free from the Journal of the American Chemical Society." From the article: "Scientists have combined two molecules that occur naturally in blood to engineer a molecular complex that uses solar energy to split water into hydrogen and oxygen. This molecular complex can use energy from the sun to create hydrogen gas, providing an alternative to electrolysis, the method typically used to split water into its constituent parts. The breakthrough may pave the way for the development of novel ways of creating hydrogen gas for use as fuel in the future."
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Blood Protein Used to Split Water

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  • by Disoriented ( 202908 ) * on Friday December 01, 2006 @05:54PM (#17073268)


    Now we just have to figure out if the amount of energy needed to synthesize the blood protein (say, X liters of hydrogen in a fuel cell) is less than
    the energy of the hydrogen produced from this process... :)


    --
    Rare 680X0 and PowerPC posters! [ebay.com]

    • Re: (Score:3, Interesting)

      by CorSci81 ( 1007499 )
      Well, we're getting pretty good at genetically engineering simple organisms to produce things like this on their own.... (think BT corn).
    • by Chris Burke ( 6130 ) on Friday December 01, 2006 @06:09PM (#17073524) Homepage
      I'd be willing to bet that this compound can be used to break multiple water molecules, just like our hemoglobin can carry another oxygen molecule after it drops one off. The source of energy that allows continued hydrogen production is the sun.

      In which case, the main question is the rate at which you can produce hydrogen. How much of the substance do you need, and how much solar energy, to produce how much hydrogen over what period of time? That is what will define whether or not this is a practical method of producing hydrogen. One obvious point of comparison would be an equal-sized photovoltaic solar cell and water electrolysis machine. If it doesn't do better than that, it's pretty worthless. On the other hand it might be a very efficient way to convert solar energy into hydrogen gas for fuel cells, which would be sweet.

      Not to mention the other possibilities it opens up in biochemistry. These proteins are fascinating, as is the idea of swapping out the bound metal atom to get different effects.
      • by sillybilly ( 668960 ) on Friday December 01, 2006 @07:53PM (#17075270)
        Yes, but most biological matter is easily degraded by UV radiation, plus infection - bacteria would love to feast on your new solar cells.
        As a sidenote, to quote the artilce: "Dr Stephen Curry Opens in new window, a structural biologist from Imperial College London's Division of Cell and Molecular Biology who participated in the research explains: "This work has shown that it is possible to manipulate molecules and proteins that occur naturally in the human body by changing one small detail of their make-up, such as the type of metal at the heart of a porphyrin molecule, as we did in this study.
        Naturally occur in a human? I was hoping they'd be talking about cow-derived materials, unless they are interested in genetically engineering photosynthetic human beings? Maybe one of our great great grand children will be engineered enough to be vacuum resistant and fully photosynthetic, then he can fly around in outer space while living off of sunshine.
    • Re: (Score:3, Interesting)

      by Foofoobar ( 318279 )
      Actually they say it far surpasses the current method of separation and assuming this is a passive process (much like solar power), unless the production costs are over a million dollars for one unit, the time it would take to pay for itself is nominal.
      • Re: (Score:3, Informative)

        by radtea ( 464814 )
        Actually they say it far surpasses the current method of separation and assuming this is a passive process

        They say nothing of the kind. Quote from the abstract, "The efficiency of the photoproduction of H2 was greater than that of the system using the well-known organic chromophore, tetrakis(1-methylpyridinium-4-yl)porphinatozinc(II ) (ZnTMPyP4+), under the same conditions."

        Note the complete lack of superlatives.
        • Re: (Score:3, Funny)

          by Foofoobar ( 318279 )
          Note the complete lack of superlatives.
          So greater!=surpasses? I'd suggest a dictionary if I thought you literate enough to even understand what a superlative is.
    • Now we just have to figure out if the amount of energy needed to synthesize the blood protein

      How much energy is required for pig farm?

      Genetically engineered pigs that is...
    • by Pedrito ( 94783 ) on Friday December 01, 2006 @07:23PM (#17074774)
      Though it doesn't specify, it's highly unlikely that albumin or porphyrin is used up in the reaction. Instead, it likely cleaves the water molecules (the substrate). Not quite physically tearing it apart, but that probably isn't an entirely inaccurate description either. Many proteins perform functions like this on other molecules. They'll attach to part of the substrate and remove, say an -OH hydroxyl group, or some other piece of the molecule. This is how liver enzymes breaks down certain drugs so that the byproducts (called metabolites) can be removed from the blood by the kidneys. As someone else mentioned catalase from yeast, it works in a similar way and removes an oxygen molecule off of hydrogen peroxide, leaving water and oxygen, but the catalase isn't "used up" in the process.

      That said, proteins don't usually last forever and how long they last largely depends on how hostile their environment is, and what constitutes a hostile environment for a protein varies from protein to protein.
    • Easy answer - in a closed system, total entropy will always increase. Which means that the bigger the system is that you consider, the less likely it is easy that you will actually be able to truly generate energy. At some point, it all boils down to shifting energy from one place to another, or storing it for use at a later time. Which means that by definition, you will use waste at least some energy in that process.

      The real question is: what's the cost of producing energy in this fashion, and are we willi
      • Re: (Score:3, Informative)

        by wetfeetl33t ( 935949 )
        Yes, that's true if this were a closed system. However, this isn't a closed system. Energy is entering it (from the sun), and mass is entering and leaving (water, hydrogen and oxygen). So yes, total entropy is increasing somewhere, but it just isn't in this hypothetical system
    • Re: (Score:3, Insightful)

      Comment removed based on user account deletion
    • Re: (Score:2, Insightful)

      by Tumbleweed ( 3706 ) *
      Now we just have to figure out if the amount of energy needed to synthesize the blood protein (say, X liters of hydrogen in a fuel cell) is less than
      the energy of the hydrogen produced from this process... :)


      This statement _really_ old, and completely misses the point.

      It takes more energy to find, drill for, pump, process, and ship oil, than you ever get out of it. That ain't the point, either.

      The POINT is to have a MOBILE fuel (or energy transfer medium, or whatever you want to call it; it's semantics at t
  • by User 956 ( 568564 ) on Friday December 01, 2006 @05:57PM (#17073312) Homepage
    The Imperial College in London is reporting that genetically-engineered blood protein can be used to split water into oxygen and hydrogen.

    I can hear it now... "No blood for oil! or hydrogen!"
  • I wonder how this compares to other methods such as solar power? Do you have to refuel this? How expensive is it to produce, install, and care for compared to solar panels. Makes me think of the book Distraction - maybe it'd be a good method for people that have time to care for it but not a lot of money?
    • by kebes ( 861706 ) on Friday December 01, 2006 @06:38PM (#17074008) Journal
      I'm reading over the actual article right now. It seems that process is quite efficient. In the conclusion of the paper they note:

      Currently, rHSA(wt) is manufactured in an industrial scale, which allows us to use this zinc-protein photosensitizer in practical applications
      Thus the raw materials are cheap enough that one could imagine scaling this up significantly. Moreover since its behavior is catalytic, the protein isn't used up, so you wouldn't need to replace it very often.

      With regard to efficiency, in the Abstract they also point out that their system is more efficient than the previous standard in organic photo-synthesis:

      The efficiency of the photoproduction of H2 was greater than that of the system using the well- known organic chromophore, tetrakis(1-methylpyridinium-4-yl)porphinatozinc(II ) (ZnTMPyP4+), under the same conditions.
      Since the discovered system is a photosensitized catalyst, it effectively is a new kind of solar power. However it is one that directly generates H2 from incident light, without requiring one to harvest light energy as electricity, store it, and then use it to split water. So this discovery, coupled with cars/devices that run on H2 efficiently, seems like a viable idea. Of course we'll have to wait and see whether this really pans out, but from this paper it does indeed seem that this is a feasible way to harvest solar power (and store it as H2).
      • by misleb ( 129952 )

        With regard to efficiency, in the Abstract they also point out that their system is more efficient than the previous standard in organic photo-synthesis:

        Ok, HOW efficient is it though? I'd like to compare it to solar panels. Is there any indication of how much energy you could extract from sunlight? Is there an optimal protein density and water depth for breaking down water?

        It would be cool if anyone could put something the size of a kiddie-pool outside and collect H2 all day.

        -matthew

      • Re: (Score:3, Informative)

        Not sure about the recombinant albumin, but part of my job involves pharmaceutical purchasing, and a vial of 20mL of 25% human serum albumin can be obtained for approximately $13. The human version is produced by precipitation from donated blood and is used quite routinely in the hospital to treat various conditions such as shock or malnutrition. Also, many medications are packaged with albumin in the vial (to provide a binding surface for the drug molecules).

        I would say though that the "manufactured i
    • Re: (Score:2, Funny)

      by jalet ( 36114 )
      > Do you have to refuel this?

      Yes, but they are still wondering if it's better to refill this stuff with water, or with human bodies...
    • Re: (Score:2, Funny)

      by smackt4rd ( 950154 )
      Just catch some small animals and stuff them in the gas-tank. :)
      • by MikeFM ( 12491 )
        A new use for road kill - let your car collect it and use it as fuel. Just watch out for small children. People whine so much if you run over their kids let alone if your car digests them for a fuel source.
    • I wonder how this compares to other methods such as solar power?

      It is solar power.

  • by __aagmrb7289 ( 652113 ) on Friday December 01, 2006 @05:59PM (#17073344) Journal
    I eagerly await the return to the days of human/animal sacrifice. "It's for the good of the country! We need to have more SUVs on the road!" Bow down, I say!
    • by Skidge ( 316075 ) on Friday December 01, 2006 @06:05PM (#17073482)
      The Red Cross can just roll it into their blood drives: "Give a pint of blood and fill up your hydrogen tank!"
      • by Greyfox ( 87712 )
        Actually they probably could use blood from them. I seem to recall that blood doesn't keep very long and they have to throw a lot out. That waste might not be suitable for use in humans anymore but it should still be full of harvestable proteins.
    • by TimToady ( 52230 )
      They've already got the sacrifice part covered:
      "...In the presence of the colloidal PVA-Pt as a catalyst and triethanolamine (TEOA) as a sacrificial electron donor, the photosensitized reduction of water to H2 takes place."
    • by Duncan3 ( 10537 )
      Await the return? Every war over oil (all current wars) is exactly that.
  • Comment removed (Score:5, Interesting)

    by account_deleted ( 4530225 ) on Friday December 01, 2006 @06:01PM (#17073402)
    Comment removed based on user account deletion
    • Re: (Score:2, Interesting)

      If we're lucky, you'd not only get clean water, you'd get an abundance of (clean, perhaps?) energy that could be converted to electricity.
    • Re: (Score:2, Interesting)

      by hadhad69 ( 1003533 )
      The NaCl in the sea water may interfere with the catalytic pathway in question, its another story altogether really
    • by Boronx ( 228853 )
      I'd bet if you exposed this enzyme to ocean water, something is going to eat it. If you kill everything in the water first, there will still be something that breaks it down.
    • by misleb ( 129952 )
      Well, maybe AFTER running it through a fuel cell to make electricity. Otherwise you'd be wasting one heck of a lot of energy to make minimal amounts of water. You'd have to burn a lot of hydrogen just to get a glass of water.

      -matthew
  • by b0s0z0ku ( 752509 ) on Friday December 01, 2006 @06:01PM (#17073408)
    Blood also contains a protein called catalase. It makes the hydrogen peroxide that you put on a wounds bubble up with little oxygen bubbles. Yeast contains the same protein. Mix yeast and 3% peroxide solution and you get ------ oxygen and water. Stick a burning match in it and it burns with a bright white flame like a welding torch.

    -b.

    • Not to sound like some sort of a bitch, but do you mean oxygen and hydrogen?
      • Not to sound like some sort of a bitch, but do you mean oxygen and hydrogen?

        No, I mean:

        2H2O2 --> O2 + 2H2O

        (can't seem to get subscripts to work!)

        -b.

  • efficiency (Score:5, Informative)

    by drDugan ( 219551 ) * on Friday December 01, 2006 @06:02PM (#17073424) Homepage
    The mention efficiency many times in the article, but do not mention the most important efficiency number - that is total energy in/out.

    So, a quick calculation of efficiency:

    FTA

    Light in:
    6 hours, 450 W light = 2.7 kWh

    H energy out:
    0.044 mL H ... at 4.7 MJ/L (Wikipedia) * 1/1000 (L/mL) * 1/3.6e6 (kWh/J) * 1e6 (J/MJ) =

    = 5.7 e -5 kWh

    Disclaimer:

    This probably has an error, please help me correct it.

    It has been a really long time since I did physics or dimensional analysis.

    I could not find in the paper the pressure for the 0.044 ml of generated hydrogen, nor it's weight, so I made a gross assumption the energy density listed in Wikipedia (at 700 bar) was close enough.

    Regardless, if you put in 2.7 units of energy and get out 0.000057 units... that seems really (s)low.

    • Re:efficiency (Score:5, Insightful)

      by TubeSteak ( 669689 ) on Friday December 01, 2006 @06:10PM (#17073540) Journal
      Regardless, if you put in 2.7 units of energy and get out 0.000057 units... that seems really (s)low
      Even if your math is off, it might not matter if the process can be scaled up, since solar power is cheap/free.

      The important question is how cheaply can they synthesize the needed protein.
      • by jafac ( 1449 )
        Presumably this protein catalyst can be manufactured on a much larger scale than solar cells.

        Solar energy is free (well. .. as "free" as the square-footage of land on which you situate your collectors) - but solar CELLS aren't free.
    • by radtea ( 464814 )
      could not find in the paper the pressure for the 0.044 ml of generated hydrogen, nor it's weight, so I made a gross assumption the energy density listed in Wikipedia (at 700 bar) was close enough.

      1 bar is more likely, so the miniscule efficiency you've computed needs to be reduced by a further factor of 700.

      Thanks for providing these numbers, which look quite sensible. I don't have access to the article, and neither the abstract nor the press release contain any information that would be useful in evaluati
    • This is exactly the point. It's nice that we can now use sunlight and a protein to split water and make hydrogen, but indeed, How efficient is the process? Screen printed poly-crystalline solar panels are about 12-15% efficient and produce around 120-150 W/m2... directly (=very convenient). Can this new method do any better? Let's hope so, because otherwise we might as well use solar panels to produce electricity to split water.
    • The energy of the light bulb (didn't read the article, I'm assuming that's what was used) is radiated out in a sphere. If more of the energy is absorbed by a larger container, or a container more closely positioned to the light, or any other method of more efficiently using the light radiated by the bulb, you can dramatically scale up the efficiency of the process. That's why incident light energy is generally measured in W/m^2, not straight W.
  • What does your car run on?

    Mine runs on blood, sweat and tears! =) /stupidity
  • Doomsday weapon? (Score:3, Interesting)

    by Reality Master 101 ( 179095 ) <[moc.liamg] [ta] [101retsaMytilaeR]> on Friday December 01, 2006 @06:04PM (#17073460) Homepage Journal

    I wonder if you could bioengineer a plant that could survive in the ocean similar to seaweed, which would secrete this chemical. Eventually all the oceans would turn into Hydrogen and Oxygen... and LIFE WOULD BE DOOMED! Bwahahaha

  • However, one of the scientists went too far, and replaced every iron atom at the center of his porphyrin molecules with zinc, transforming him into Hydro Man -- but only when he went out into the sunlight.
  • Don't anyone tell the Machines about this, otay?

    So, all we gotta do is ship water up into orbit at $10,000 per pound and gain access to 24 hour light, then let the hydrogen ships drop back down where we can pick them up.

    Or perhaps something more reasonable. If we do this, we can also probably eliminate salt mines with all the salt we'll be taking out of the water at the same time. Yay, no more salt mines!

    Now all we need is some of those nifty carbon nanotube wall fuel tanks to store enough hydrogen to make
    • Yeah, I'm thinking this is the type of power generation they were talking about in the Matrix. First I find out that there is in fact a company that makes advanced robotics called "skynet", then the crazy idea of buring the sky to prevent global warming (stupid eco-terrorists!), now this!

      Beware of the machines.
  • Thank you! (Score:5, Insightful)

    by mapkinase ( 958129 ) on Friday December 01, 2006 @06:16PM (#17073648) Homepage Journal
    I would like to praise the submitter for providing a link to a peer-reviewed article. Does not happen very often, worth mentioning.
  • Next: (Score:5, Insightful)

    by jafac ( 1449 ) on Friday December 01, 2006 @06:18PM (#17073672) Homepage
    We'll need one of these that can split Oxygen and Carbon.

    (ie - remove Carbon Dioxide from the atmosphere, and plant the Carbon somewhere safe - like maybe in empty petroleum resevoirs, where it came from).
  • Finland made hydrogen fuel cells that they use for many things such as electricity when boating. They say it only takes 8 fuel cells to theoretically power a car, but the article I read was years old. I've been told Finland already has electric cars.

    Heresay, I do say.
  • I look forward to not having to breath anymore. I could just stand out in the sun and drink some water. Is there a chance that I'd split all the water in my blood and dessicate like a raisin? Then there is the matter of all that leftover hydrogen. Would I burst like the Hindenburg? Oh the humanity!
  • A gill pack would be nice for walking around on the other 3/4 of the planet.

    Though it's not the same, as I think fish get oxygen from dissolved free oxygen, not by splitting H20.

    What to do with all this extra hydrogen?
  • by quoll ( 3717 ) on Friday December 01, 2006 @06:40PM (#17074050)

    I'm pleased to see alternative technologies to split water using sunlight, but the idea is not new.

    There is a group at UNSW [sialon.com.au] who have been working on ceramics which use sunlight to split water (via a process of electrolysis). It's still in research (mostly due to efficiency), but it's an interesting option if you're interested in this stuff.

    Their website is pretty sparse, but there is a story on them here [abc.net.au].

  • Can anyone specuate as to whether or not a similar technique could be used to split 2CO2 into 2CO+O2? That would be rather useful as well provided the CO could be fixed elsewhere.
    • Re: (Score:2, Insightful)

      by noigmn ( 929935 )
      Yeh was thinking the same. If we could break down carbon and sulphur compounds in the air, it would be a big step forward in fixing global warming. And also in atmospheric engineering, which we might need if we decide to create an atmosphere on Mars.

      Imagine if photosynthesis could work with whatever compound we wanted. We could have it on space ships to break the CO2 breathed out back into O2 to rebreath also. Might also work for divers.
    • It's called a 'tree'. It removes an oxygen molecule from every carbon dioxide molecule, then you burn it in low-oxygen conditions to get CO. It uses a series of light-activated enzymatic molecules to do this, as described in the article.
       
      Merry christmas.
  • I suspect that many of our most vexing engineering problems (efficient energy production and storage, advanced pattern recognition, to name just two) have already been solved at the molecular level by our cells. The answers to these problems are as close as our own DNA.

    In college in the late 80s, I double-majored in Computer Science and Biology because I was convinced that the next huge advance in technology would be come from advances in genetic engineering. The Human Genome Project was an exciting first
  • by fahrbot-bot ( 874524 ) on Friday December 01, 2006 @06:56PM (#17074330)
    ...something on the bleeding edge of technology here on /.

    Ok, ok, OK. I promise not to post for the entire weekend, sigh.
    Damn.

  • by The Step Child ( 216708 ) on Friday December 01, 2006 @07:05PM (#17074446) Homepage
    From the abstract:
    In the presence of the colloidal PVA-Pt as a catalyst and triethanolamine (TEOA) as a sacrificial electron donor, the photosensitized reduction of water to H2 takes place.
    My chemistry knowledge isn't really up to the point where I can fully understand the whole abstract, but it sounds like we still need triethanolamine as a source of electrons in order to reduce water to H2. So the energy needed to produce more triethanolamine could put a big dent in the net energy gained from the H2 produced when we're talking about the practical large-scale usefulness of this. Maybe one day we could use another (renewable) electron donor like NADPH, so that we can couple it to another biochemical process like photosynthesis in order to renew our electron donors :)
    • Re: (Score:2, Informative)

      by Anonymous Coward
      Right on the money, it's hard to believe the Journal of the American CHEMICAL Society would publish this as is. First, water is not reduced; protons are reduced. If they had added a little acid, they could have claimed "photosensitized reduction of acid X" just as well. Second, as you mentioned, triethanolamine is a sacrificial reductant. So, the Slashdot title is misleading--water is not being split (which in the scientific jargon means reversing combustion of hydrogen, i.e. net reaction 2H2O --> 2H2 +
  • The abstract also mentions "In the presence of the colloidal PVA-Pt as a catalyst and triethanolamine (TEOA) as a sacrificial electron donor, the photosensitized reduction of water to H2 takes place." This basically means that electron fro TEOA is being used to reduce water to hydrogen. This chemical (TEOA) is oxidized and has to be replenished to maintain the H2 production rate. I am not disparaging their results (they are valuable, otherwise it would not be published in such a reputed journal), but tryin
  • If my h20 splittting car has a hole in it's pipes, would it be leaking or... bleeding?
  • I have high hopes for this because it could enable hydrogen to replace fossil fuels as our main source of energy. This would enable the continuing trend of increase personal energy consumption. Enabling personal energy consumption raises standards of living and therefore it is consistent with liberal and progressive values.

    Enabling an increase in personal energy consumption for all is a more moral stance than the current emphasis on conservation.
    • Indeed. Progressive, and not a good idea in general.

      You realize that the progressives were the crazy, impractical party absorbed by the democrats that correspond to the impractical overreacting Libertarians' relationship with the Republicans, right? What I'm telling you here is that you're right, but you're also being impractical in your basic goals.
  • Don't vampires have prior art on this? Vampire is exposed to solar energy, blood seperates water into hydrogen and oxygen, vampire bursts into flame. It explains everything.
  • Comment removed based on user account deletion
    • something like .06$US per scm, if I recall correctly. That was for purchases in oxidation-reactor quantities, though, so you might want to look it up yourself.

      Also, most of the cost of bought oxygen comes from compressing/cooling it to a liquid and then shipping it, not producing the stuff itself.
  • A beowolf cluster of those!
  • by alchemist68 ( 550641 ) on Friday December 01, 2006 @10:26PM (#17076892)
    Porphyrin chemistry is very interesting and has been studied for over 100 years. This news is both exciting and old news, because porphyrins and related isomers have been the subject of continued research. For very detailed information about porphyrin chemistry, refer to The Porphyrins edited by David Dolphin. Also, review the research of Martin Gouterman. In biological systems, porphyrins are found commonly in heme-type proteins used for oxygen transport and cytochrome P450 in the liver for metabolizing biological compounds including pharmaceutical products, and as chlorophyll in plants. Porphyrins have served as catalysts for organic reactions in industry, photodynamic therapy for cancer, molecular devices including sensors and switches, and model compounds for the active sites of enzymes. My thesis, which available for download through OhioLink:

    http://www.ohiolink.edu/etd/view.cgi?akron11339504 18 [ohiolink.edu]

    details the photophysical characterization of N-Confused tetraphenylporphyrin and characterization of zinc N-Confused tetraphenylporphyrin.

    Upon reading this post on Slashdot, I was pleasantly surprized that the subject of my thesis has some similarities to a related compound that could be used for further research into catalyzing an energy source. In one way I'm surprized, and in another I'm not, and I'm glad that one of the Slasdot crowd submitted the post. Porphyrin chemistry is vast, interesting, and complex.

    Happy reading!
  • Sacrifical Donor (Score:3, Interesting)

    by Roxton ( 73137 ) <roxton@gmail.COMMAcom minus punct> on Saturday December 02, 2006 @01:17AM (#17077964) Homepage Journal
    n the presence of the colloidal PVA-Pt as a catalyst and triethanolamine (TEOA) as a sacrificial electron donor, the photosensitized reduction of water to H2 takes place. [Emphasis mine]
    Isn't this a problem? How do you restore the triethanolamine without using energy?

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