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."

Comments

Medical use?!

[Raptoer]

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.

Lack of details!

[flajann]

"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.

Your Body Is a Submarine

[Doc Ruby]

"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!