Moving Water Molecules By Light 96
Roland Piquepaille writes "An interdisciplinary team of researchers at Arizona State University (ASU) has discovered a new nanotechnology effect, the ability of moving water molecules by light. This is a far better way than current methods such as damaging electric fields and opens the way to a new class of microfluidic devices used in analytical chemistry and for pharmaceutical research. For example, this makes possible to design a device that can move drugs dissolved in water, or droplets of water and samples that need to be tested for environmental or biochemical analyses. Please read this overview for more details and references, plus an image of two water drops illuminated with a fluorescent dye and sitting respectively on a nanowire surface and on a flat surface."
Re:True or not? (Score:5, Informative)
This effect itself isn't all that new... it's in all those stain-repellent pants that are being sold now. Being able to control the effect with light is.
RTFA (Score:5, Informative)
It's about changing the hydrophobic/hydrophilic (water repellent/attractive) properties of a _special_ surface using light. This doesn't work on just any surface.
I dare say the military would prefer to dehydrate parts of your body by vapourizing bits of it e.g. zap you directly with a powerful beam of light. Or ionizing air between a thundercloud and you so that a lightning bolt zaps you ( that's to make it look like an "Act of God").
Please stop (Score:5, Informative)
Hemos seems to usually be the culprit posting the Piquepaille stories. I don't mind if Hemos wants to post stories submitted by this guy (though often even the submissions are inaccurate summaries of the original articles), but it would be appropriate to edit out his links to poorly written, uninformative summaries that he posts on his blog before posting the story. I don't mind somebody occasionally using a Slashdot submission to let the community know about some new product they or their company has developed or interesting article or book they've written, but this blatant traffic farming is way over the top.
Let me indulge in some whistleblowing (Score:1, Informative)
I happen to know that Piquepaille is just a karmawhore whose aim is to make money for anti-slash with his ad-links.
Devious, isn't it?
Clues here (Score:2, Informative)
To address your other point, electric fields can be very damaging when they are sufficiently high intensity. Also, electromagnetic fields can be damaging too.
Not damaging to the water molecules, which are robust, but damaging to the materials disolved or suspended in the water, which may be delicate bio-active organic molecules. For example, there are various cell sorting systems that currently use electric fields. They might better use a system like this.
However, light can be damaging in its own right. Red and infrared light can be heating. Violet and UV light can be energetic and penetrating (think sunburn radiation damage).
Re:Damaging Electric fields? (Score:4, Informative)
By damaging electric fields, I'd guess they mean what is used in capillary electrophoresis (Several kV are used to generate a 'zeta potential' which consists of the counterions on a glass surface moving in the electric field, and dragging water along with them). Such high voltages can have bad effects on large proteins and other things (like living cells) that you might want to move, but not electrocute (let alone boil, which happens if you crank up the voltage to make things move faster).
IAAC (I am an analytical chemist), and in my humble opinion this is interesting, but not immediately practical, not as expansive as the article suggests (surprise!).
Kudos to the researchers, and I want to get 10 yards of light-actuated water droplet moving wire once they have it :)
Francis