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Janus Particles as Body Submarines?

ScuttleMonkey posted more than 6 years ago | from the beginning-to-see-the-light-at-the-end-of-the-tunnel dept.

Medicine 42

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."

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Cut the jibba jabba! (3, Funny)

BadAnalogyGuy (945258) | more than 6 years ago | (#22608914)

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!

Re:Cut the jibba jabba! (1, Funny)

MadUndergrad (950779) | more than 6 years ago | (#22608978)

And yet your post was modded informative. Oh the irony.

Re:Cut the jibba jabba! (0)

Daimanta (1140543) | more than 6 years ago | (#22609200)

And your post was modded Funny. Oh, the irony.

Re:Cut the jibba jabba! (4, Funny)

rbanffy (584143) | more than 6 years ago | (#22609740)

Actually, the part that deserved the informative mod is the one that said that everyone knew that. I had no idea, before reading the post, that so many people knew about anisotropic particles and unbalanced liquid flows caused by electric fields applied to aqueous suspensions of them. ;-P

Re:Cut the jibba jabba! (0)

Anonymous Coward | more than 6 years ago | (#22608984)

You've actually read the article?


Re:Cut the jibba jabba! (3, Funny)

Vlad_the_Inhaler (32958) | more than 6 years ago | (#22609256)

I am more interested in the legal implications of targeted drug delivery - who is responsible if these couriers are arrested? Janus is not within the jurisdiction of the US so my guess is that the researchers will be held to account.

Mouse on the Moon (0)

Anonymous Coward | more than 6 years ago | (#22631370)

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.

Janus particles (-1, Flamebait)

Anonymous Coward | more than 6 years ago | (#22608940)

Janus Particles? More like anus particles...

Re:Janus particles (1)

Anonymous Coward | more than 6 years ago | (#22609796)

You missed a trick there. It should have gone something like....

"The name's Janus. Hugh Janus. [] "

...complete with obligatory troll link.

(And if you're thinking of modding me down for the link, take a closer look. :-) )

Why can't we have cool gods like Janus? (0)

Anonymous Coward | more than 6 years ago | (#22608954)

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.

Precisely (0)

Anonymous Coward | more than 6 years ago | (#22608980)

Just as L. Ron Hubbard described fifty years ago.... Modern medicine is finally catching up it seems.

Re:Precisely (0)

Anonymous Coward | more than 6 years ago | (#22611770)

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!

Finally! (4, Funny)

jovius (974690) | more than 6 years ago | (#22609016)

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?

Re:Finally! (0)

Anonymous Coward | more than 6 years ago | (#22611008)

Well there's certainly more than a few macroscopic particles in the government that could really use an alternating electrical field applied to them.

Sounds Like... (0)

Anonymous Coward | more than 6 years ago | (#22609036)

this could lead to a fuckin' fantastic voyage!

You can legalize marijuana in 2008! No bullshit! (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#22609046)

On January 24th, the California Supreme Court ruled that employers can fire workers who use medical marijuana even if it was legally recommended by a doctor.

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5(b): "Testing for inactive and/or inert residual cannabis metabolites shall not be required for employment or insurance, nor be considered in determining employment, other impairment, or intoxication." ..
Now all we have to do is get this initiative on the ballot to fix this problem. We need everyone's help with this. Please visit [] for more information on how you can help.
The only way to reverse the Greenhouse Effect is with Cannabis Hemp. It makes the best fuel on Earth, as well as the best paper, fiber, food and medicines. Californians are smart to use this wonderful plant and should not be threatened with losing their jobs for it.

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. People who smoke pot but don't smoke cigarettes or drink alcohol will live approximately 8 to 24 years longer than those who do smoke cigarettes and drink alcohol. This was proven in studies done by Dr. Vera Ruben on Rastafarians in Jamaica from 1968 to 1974. The Rastafarians lived up in the hills and were the poorest people in Jamaica. Everyone expected them to have the shortest lives but instead they had the longest lives. They smoked pot morning, noon and night. This study cost $6,000,000.00 and was an extremely comprehensive study. If the same study was done today it would cost approximately $125,000,000.00.

We can do something about this if we have all of you helping us. We only have until the middle of April so let's get to work!!! Thanks!

Save the world for 24 bucks -
12 bucks if you dont have 24

If we legalize Cannabis Hemp in California this year, just imagine what life will be like a couple of years from now. Almost everything we use in our daily lives will be made from hemp.

  We won't have to feel guilty about going to places like McDonald's or Burger King anymore because the packaging will be made from hemp (not trees). You'll have your choice between a cow burger and a hemp burger. Cheese too. Hempseed is the finest food on the planet, bar none. It helps clean out your arteries. And it tastes great. It can be made to look and taste like just about anything you want it to. You can have hemp ice cream for dessert!

No more smelly exhaust fumes coming out of our cars. We'll be using the finest fuel in the world and we won't have to shoot anybody for it. The CO2 levels will be drastically reduced. The only way to reverse the Greenhouse Effect is by growing hemp all over the globe and leaving all trees and fossil fuels (gas, oil and coal) in the ground.

Our cars will be made of hemp too! Henry Ford built a car made of hemp right before World War II. He predicted that all cars in the future would be made from hemp or other plants. There's a little video on YouTube showing him hitting the back of the car with a sledgehammer to demonstrate how strong it is and how it wouldn't make a dent.

Our houses will be made almost completely from hemp. It is a non-toxic replacement for cement, lumber, sheetrock, plaster, insulation and acoustic tiles. Because of its strength and flexibility, it makes an ideal construction material for areas susceptible to earthquakes, tornadoes and hurricanes. It is non-flammable, fungicidal, antibacterial, waterproof and inedible by rodents and termites.

Just about everything inside our houses will be made from hemp, too, including carpets, drapes, furniture upholstery, paints, varnishes, shampoo, conditioner, soap, lotions and creams. Also, anything made out of plastic, including computers, speakers, DVD holders, window blinds, food packaging, etc.

All of our clothing can be made from 100% hemp or hemp blended with other fabrics like organic cotton or silk. You can even make fake fur out of hemp! And no pesticides are required to grow it, unlike non-organic cotton. Fifty percent of all poisons used for agricultural crops in the United States are used just on non-organic cotton.

We won't be killing ourselves with pharmaceuticals anymore. We'll be using natural cannabis for most of our ailments. It's the best thing for Alzheimer's, multiple sclerosis, migraines, ALS (Lou Gehrig's disease), Parkinson's, sickle cell anemia, attention deficit disorder, nausea, cancer, fibromyalgia and countless other problems.

Cannabis Hemp can cure Parvo in dogs, get song birds to sing, and is the best bait for fish. Horses love it, too.

Isn't it strange - doesn't it make you mad as hell - that the number one food of all time for most birds, fish, horses, humans, and life in general, is illegal to have naturally and healthfully in the United States of America, as ordered by the Nazi/Gestapo-like Amerikan Drug Enforcement Administration and, through them, the USDA?

Re:You can legalize marijuana in 2008! No bullshit (0)

Anonymous Coward | more than 6 years ago | (#22609196)

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.

Hmmm (2, Funny)

kitsunewarlock (971818) | more than 6 years ago | (#22609050)

But will pilots have to use revealing clothing? After all, that's what turns a mediocre journey into an amaaaazzzing journey.

Re:Hmmm (3, Funny)

owlnation (858981) | more than 6 years ago | (#22609212)

But will pilots have to use revealing clothing? After all, that's what turns a mediocre journey into an amaaaazzzing journey.
I think you mean a Fantastic Voyage. And beware of the Janus particle that looks a little like Donald Pleasance.

Re:Hmmm (1)

Chris Mattern (191822) | more than 6 years ago | (#22612694)

Yeah, but that means another of the particles will look like Racquel Welch. Rawr.

Medical use?! (2, Interesting)

Raptoer (984438) | more than 6 years ago | (#22609058)

The electric field was of voltage and frequency similar to the ones you'd get if you plugged a device into a socket in your home or office.
So what? we have to shock the person for this to work? Yes I know they didn't state the amp requirements, so it could be in the microamp range, but still.

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.

Re:Medical use?! (4, Insightful)

pimpimpim (811140) | more than 6 years ago | (#22609102)

Indeed, or the scheme to do the steering of such microamp fields through your body would be so damned complicated that developing this system would be either impossible or overly expensive. And at that point you still haven't thought of a decent take-up mechanism. As I said before, I am ok with Roland Piquepaille giving a shot on popular science articles, but please add some well-thought-through criticism to the PR shit that comes from universities. "Submarine" in-body medicine has been a dream since Asimov wrote about it, but please stop the unreasonable extrapolations from any nano-particle to a submarine that can save us from cancer LOL OMG!

In the mean time that these people are looking for a problem that fits their solution, a lot of REAL scientific innovation has been going on, e.g. microsensorics and subcutaneous pumps to help diabetes patients in a life-improving way.

Re:Medical use?! (0)

Anonymous Coward | more than 6 years ago | (#22610114)

It occurs to me that /. would benefit greatly from allowing you to block all articles with a named submitter. So if I wanted to put in a Roland Piquepaille filter I could do that. I left /. for months because I was sick of Piquepailles and a quick perusal does not show any new functionality to block certain submitters.

I can't even really explain WHY having certain users hit the main page over and over bugs me--it just does. Given the tags that those articles get I know I'm not alone. How hard would it be to implement a submitter block at the user level? Problem solved.

Soap? (1)

marcovje (205102) | more than 6 years ago | (#22609072)

> spheres whose halves are physically or chemically different

Sounds like soap. Or the relevant groups grafted on some substrate (dendrimer, cellulose)

Re:Soap? (5, Informative)

Schiphol (1168667) | more than 6 years ago | (#22609166)

Soap molecules are not spherical, really. They are more of like a match, with a lipophobic head and a lipophile body. Now, when they help dissolve fat in water, a number of molecules tend to form spheres, leaving the fat inside, This phenomenon has been exploited for ages to, ehm, wash dishes and the like. Also, a more sophisticated version of this idea has also been around for quite some time: liposomes [] .

The idea behind TFA is using spheres with two halves. Sort of a dipole that may move around under the effect of an electric field (if I got it right).

Re:Soap? (1)

marcovje (205102) | more than 6 years ago | (#22611070)

Which is why I made the "grafted" remark. Well defined dendrimer of magnitude 16 and higher are roughly spherical afaik. Still the asymmetric synthesis might be difficult.

Re:Soap? (1)

Hognoxious (631665) | more than 6 years ago | (#22612076)

No shit, sherlock?

Brilliant!!! (1)

g0dsp33d (849253) | more than 6 years ago | (#22609456)

...when an alternating electrical field is applied to liquid surrounding them...

Great news everyone! Now we can take our medicine in our own homes, we just need to climb into the microwave.

Define nonlinear (1)

ruinevil (852677) | more than 6 years ago | (#22609480)

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.

Not necessarily true (1)

Kupfernigk (1190345) | more than 6 years ago | (#22609628)

Air molecules move in a nonlinear fashion. Water molecules move in a nonlinear fashion. People move in a nonlinear fashion in crowds. At a macroscopic level, this doesn't mean hoses (or subways) don't work.

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?

Re:Not necessarily true (1)

ruinevil (852677) | more than 6 years ago | (#22611182)

To your hose and subway analogy, both of those are impenetrable boundaries. A water molecule and people can't really move past those boundaries without a lot of energy. You don't really control their velocity or position at a particle level, just contain them.
  The wikipedia article posted below makes it sound even harder to control. Nonlinear functions don't provide a uniform output to a uniform input.

Re:Define nonlinear (1)

Schiphol (1168667) | more than 6 years ago | (#22609638)

This [] is what they mean.

Re:Define nonlinear (0)

Anonymous Coward | more than 6 years ago | (#22611148)

It's non-linear with respect to the electric field. So, if you double the field, the velocity doesn't double (it's more or less than double).

Offtopic but Important (1, Offtopic)

TFGeditor (737839) | more than 6 years ago | (#22609512)

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)


Re:Offtopic but Important (1)

Schiphol (1168667) | more than 6 years ago | (#22609578)

I do. I had to enter manually the paragraph break in my post above, but I saw it unconfigured already when previewing it. That is, I don't think you need to post to make sure the problem remains.

Re:Offtopic but Important (1)

TFGeditor (737839) | more than 6 years ago | (#22609608)

Obviously true here on /., but not on some other discussion forums. How odd that a simple formatting issue would affect so many (but not all) users.

On affected sites, I have used different browsers (Firefox, IE, Opera) and even different machines, all with the same result, as have others.

how to make them (1)

cinnamon colbert (732724) | more than 6 years ago | (#22609630)

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

Patent infringement? (1)

jc42 (318812) | more than 6 years ago | (#22609820)

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.

Lack of details! (2, Interesting)

flajann (658201) | more than 6 years ago | (#22609832)

"The researchers Dr. Orlin Velev, associate professor of chemical and biomolecular engineering at NC State and lead author of the paper; Sumit Gangwal, an NC State graduate student; Dr. Olivier Cayre, a post-doctoral researcher in Velev's lab; and Dr. Martin Bazant from Massachusetts Institute of Technology created tiny two-faced gold and plastic particles and applied low frequency alternating current to the water containing the particles. The electric field was of voltage and frequency similar to the ones you'd get if you plugged a device into a socket in your home or office."

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.

Do such particles already exist? (0)

Anonymous Coward | more than 6 years ago | (#22609978)

When I saw the article, I immediately thought of people who cannot stand cell phone radiation. This could be the mechanism for such complaints. Could it be that such particles can be formed naturally in a human body or even evolve in our world where we are "nuked" in every shop?

Your Body Is a Submarine (3, Interesting)

Doc Ruby (173196) | more than 6 years ago | (#22610194)

"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!

Politicians are composed entirely of these (1)

MrSteveSD (801820) | more than 6 years ago | (#22610876)

Hmm, I seem to have put the entire joke in the subject line :)
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