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Janus Particles as Body Submarines?
Roland Piquepaille writes "Janus particles, which take their name from a Roman god with two faces, are microscopic 'two-faced' spheres whose halves are physically or chemically different. Now, U.S. researchers have shown that some of these Janus microparticles can move like stealthy submarines when an alternating electrical field is applied to liquid surrounding them. This could lead to new kinds of self-propelling microsensors or means of targeted drug delivery."
From the article:
The application of ac electric fields in aqueous suspensions of anisotropic particles leads to unbalanced liquid flows and nonlinear, induced-charge electrophoretic motion.
Well, duh. Everyone *already* knew that!
Janus ordered his temples to keep the doors open during wartime so that he could watch his enemies be burned alive in hot springs. The doors were closed during peacetime. In honor of this legacy janitors always keep their closets near steam piping and the month of January is dedicated to torturing and killing your enemies. We can only hope that these new particles will be built into a weapons that will live up to his great legacy.
Two faced particles that stealthy move in a liquid. Pick up any government, and you can make the same observation. I wonder if the findings of the research team are applicable to macroscopic solutions?
But will pilots have to use revealing clothing? After all, that's what turns a mediocre journey into an amaaaazzzing journey.
Ginga no Rekshiya Mata Each page.
I can see these particles having uses outside of the medical world, such as a motor with no moving parts that can be scaled down. I cannot however see these having use in medicine, since humans are great big electrical conductors who are also very sensitive to electricity being pumped through them.
> spheres whose halves are physically or chemically different
Sounds like soap. Or the relevant groups grafted on some substrate (dendrimer, cellulose)
The average lifespan in the United States is 76 for a man and 78 for a woman. But if you smoke pot morning, noon and night, you will live an average of two years longer than if you don't
Move to another country and presto, you'll have several additional years on top.
Great news everyone! Now we can take our medicine in our own homes, we just need to climb into the microwave.
lol: You see no door there!
In the abstract at the bottom, it says that the particles move in a nonlinear fashion. They don't write that it follows a sinusoidal fashion either. My definition of nonlinear is not in a straight line, which would make it difficult to control, especially considering how dynamic the circulatory system is.
Rather than hope for a front page Ask Slashdot acceptance, I decided to burn a little karma and ask here in a low reply volume discussion:
/.)
Since Friday 29 February, a number of 'net users have experienced odd behavior of discussion forums such as this one. For instance, if the problem still exists here as it does on other boards, this posy WILL NOT HAVE PARAHRAPH BREAKS (all caps to make that stand out in case it does not have said paragraph breaks). Odder still, the breaks show up during composition but not in the posted version. Only by manually entering HTML paragraph markers do paragraphs show up in the posted version.
(Note that I must actually post this to determine if the problem still exists here, so if this post looks okay, please do not assume the problem is gone net-wide (because it isn't), but only here on
Is anyone else experiencing this and does anyone have an idea what is going on? (THIS IS NOT A JOKE)
Ignorance is curable, stupid is forever.
In certain fields (e.g. audio) "nonlinear" is often used to mean not describable by the function mx + c, but here I think it means that the motion is not describable by a continuous function, which is what you expect of all very small particles in any kind of non-vacuum. Don't they teach Brownian motion nowadays?
From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
most of the methods for making these particles, which are reported in scientific jounals like Analytical Chemistry or Langmuir (both published by the amer chem soc, abstracts are free) don't use solution phase methods, eg you can make janus particles by coating a monolayer on a planar support.
untill someone figures out how to make them, it is just a lab curiosity.
beyond that, janus particles don't really solve the issues (non specific binding, toxicity, plasma half life) for in vivo reporters
You missed a trick there. It should have gone something like....
...complete with obligatory troll link.
:-) )
"The name's Janus. Hugh Janus."
(And if you're thinking of modding me down for the link, take a closer look.
These researchers had better watch out; what they're doing sounds exactly like the physical mechanism of "electronic paper". The patent enforcers are gonna be all over them when the news gets out about what they're doing. After all, patents were invented to block exactly this sort of "derivative work" based on someone else's earlier inventions.
Those who do study history are doomed to stand helplessly by while everyone else repeats it.
What galls me is how they "water-down" even the simplest of details, such as what range of frequencies were used to drive the particles. And I fail to understand what that frequency has anything to do with the 50/60 Hz that comes from your wall socket. Maybe I am missing something here. It would be far more informative to see the range -- in exact numbers -- of frequencies used and where they saw the peak performance, where the performance drops off, etc.
But then, that's my general pet peeve whenever a non-scientist attempts to report on a matter of science. Details are dropped out or distored all over the place. Just to get at even the minimal details I'll have to go to the actual scientifc publications, which, BTW, Eurekalert fails to provide any references or links to.
So, a bit of lousy reporting if you ask me, on something otherwise truly interesting.
Ruby Neural Evolution of Augmenting Topologies
"Body Submarines"? That doesn't mean some drug, it means a nanothin film I can wear on my body that lets me dive to thousands of meters under the sea!
AC current flows across the surface of human skin without chemically or physically affecting the human, if cycled at the proper frequencies. Let's see them gin up some hydrophilic/phobic janus particles that can lock together with titanium strength, but contour their shape to the body surface as defined by the AC flows across the skin. Modulating the AC flow pattern to expand out and contract again as we breathe from an air tank. We wouldn't even need special diving NOx mixes, because we wouldn't be pressured anymore into the bends.
And since the diameter of the "hull" would be only something like a half meter or so, instead of the several meters of submarine ships, we might keep structural integrity to really vast depths at which the relatively cavernous submarine ships would be crushed without internal support, given their surface:volume ratio. It all depends on the physics of the janus particle made for this app.
And given a thin dynamic surface modulated with AC across the dynamics of our flexible skin, we could even preserve our sense of touch, and even let our noncompressible hairs stick out, so we can feel the water and whatever we touch in it. Though we could selectively armor areas into gloves or other protected areas, again by modulating the AC.
On land, these sheaths could be invisible body shields, that weigh practically nothing, but redistribute force of incoming blows.
Science is cool. Science fiction, given the good science, is fun!
--
make install -not war
Hmm, I seem to have put the entire joke in the subject line :)
Please provide citations where the moonbat known s L. Ron Hubbard described this mechanism? You probably can't, BECAUSE HE WAS A MOONBAT, as are all of his followers to this date. Citation: Tom Cruise
For crying out loud, he wasn't even a good author!
Wasn't the "Janus particle" the secret ingredient in
Grand Fenwick's rocket fuel in "Mouse on the Moon"?
They changed charge to always repel. They were only found
in Grand Fenwick's Premiere Gran Cru wine.