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Enzyme Bio-Battery Runs on Ethanol
mpthompson writes "According to this article at New Scientist.com substantial progress is being made on enzyme-catalyzed ethanol based batteries to run cell phones and laptops. Such batteries promise to be cheaper, safer and less toxic than previously demonstrated methanol based fuel cells."
I really wonder how do something as sensitive as enzyme withstand the working temperature of a computer
There is a whole industry based on developing crosslinked enzyme crystals which are useful in industrial applications as catalysts. The crystals are literally poured out of plastic bottles as a powder and many can function in organic solvents (which would completely denature ordinary enzymes). The cross-linking holds together the overall tertiary structure of the enzyme, and the enzyme tends to hang onto water where it needs it to maintain secondary structure.
I don't know exactly how thermally stable they are, but I imagine they can take quite a bit. While the technology probably hasn't been applied to the enzymes in question I imgaine that if the money was there it could be done.
i know huge amount of amount of electricity is required to extract hydrogen. But this can be easily generated using Nuclear Power Plants - a very clean source of electricity.
use hydrogen fuel cells in the cars, and you will take care of the pollution problem.
Actually, the best way of producing hydrogen isn't electrical. You catalyse a hydrocarbon into (usually) hydrogen and CO2. The CO2 production is very small and can be easily captured and recycled in processes that require CO2 as an input (eg photosynthesis).
In fact, that's precisely what this fuel cell does. I think they're calling it a battery because people think fuel cells are like four foot high things that cost thousands....
There are other enzymes that tolerate boiling, and other extreme conditions. They are inactive in the severe condition, but have such a stable tertiary structure that they snap right back when put into the proper environment again. Mammalian RNAses are notorious for this.
From the article, however, the restriction of the enzymes to these pockets may help. For those that don't know, enzymes have a structure like a ribbon (or several ribbons) that fold back on themselevs in a particular way. By thermodynamics, as you add heat, you add entropy and the ribbon moves around too much to stay in its functional orientation.
Keeping the enzyme in a small, restrictive pocket may restrict its random motion enough to help keep the ribbon from unfolding, allowing the enzyme to function at a higher temperature than it normally would.
There is a reason for everything. Sometimes that reason just sucks.
In fact, the article from the New Scientist needs to be completed by reading this press release from the American Chemical Society. You also can read this article from Boston.com to get more information.
Yes, as I'm also involved in biochemistry/mol. genetics, there are Heat-stable enzymes, but remember, field-conditions are not like lab conditions, where we can add as much and replace as much enzyme as we want, and it's not that the enzyme is stop then it's stopped.
;-)
When it comes to laptop, we need a stable power supply.. who wants a supply that only work in 20oC < x < 40oC (the actual margin may well be stricter)...
but a Li-Ion backup will fix this...wait.. isn't that a big weight added on it.. oh...
Methanol is simply not that toxic. If you drink large quanities (ie, ounces), it causes a condition called acidosis, which leads to blindness and death (among other things). Trace amounts are easily eliminated from the body. If you don't drink it or bathe in it, you will be fine.
love is just extroverted narcissism
The cross-linking holds together the overall tertiary structure of the enzyme, and the enzyme tends to hang onto water where it needs it to maintain secondary structure.
For those of you that don't know anything about proteins, tertiary structure refers to the way a protein folds. Since for proteins, shape is critical to function, if the bonds holding the tertiary structure are broken, the protein won't function properly.
Just for thoroughness, primary structure is the sequence of amino acids, secondary is a shape adopted before folding, and quaternary is the way multiple polypeptide chains join together.
if it's below 140 proof (70% strength), ethanol (and methanol) does not burn, but could still be useful in such power cells.
Way back when F1 and Indy cars ran on ethanol. The danger with them was that if there was a fire, the flames were not visible. You would occaisionally see a driver hop out of a car doing the funky chicken, because he was on fire, and not see any flames...
But fighting them with water was much easier than with gasoline fires.
Of course, now everyone is back to gasoline. I wonder what would happen to diesel technology if F1 or somesuch changed to diesel engines?