Using lab-on-a-chip technology for DNA detection and analysis is one specific goal many researchers are inching toward. Researchers have now offered a way to align DNA strands to allow for analysis within a nanofluidic channel. The difficulty and cost of creating nanochannels is an impediment, but new research, published in Biomicrofluidics, offers the use a cost-effective material that could garner long term results in DNA analysis.

Nanochannels offer a way to align and analyze long biopolymer molecules such as DNA with high precision at potentially single basepair resolution. In the article "Complementary metal oxide semiconductor compatible fabrication and characterization of parylene-C covered nanofluidic channels with integrated nanoelectrodes," published today in Biomicrofluidics, Chih-kuan Tung, Robert Riehn, and Robert H. Austin, present a novel method of fabricating nanochannels with parylene, while measuring impedance characteristics with 25 nanometer thick electrodes. Parylene-C is a cheap and robust material, which is typically used for coating printed circuit boards as well as stents, defibrillators, pacemakers, and other implanted medical devices.

The researchers believe that this technology will open up opportunities for electronic detection of charged polymers, and that "with techniques to fabricate nanoelectrodes with nanochannels, it should be possible to include integrated electronics with nanofludics, allowing the electronic observation of a single DNA molecule at high spatial resolution."

Enough with these housekeeping details, how about that article on describing pizza tossing with nonlinear differential equations?

There's more microfluidics here than meets the eye... yes, of course we have to worry about how the sauce flows, but what Drs. Yeo and Friend have done here is use the physics of tossing dough to design SWUMS—standing wave ultrasonic motors. The motors are only about 250 µm wide and could travel through blood to take on dangerous bodily intruders one-on-one.

If you think these two have done enough research, you haven't been reading the New Scientist. In this NS online article, Dr. Yeo explains how his group has used surface acoustic waves to create a type of earthquake on a microchip. The earthquake converts the drug into an extremely fine mist that can then be absorbed quickly through the skin into the bloodstream. The research article appeared in Lab on a Chip.

Oh yeah, and there's this super cool video too:

Enough with these housekeeping details, how about that article on describing pizza tossing with nonlinear differential equations?

There's more microfluidics here than meets the eye... yes, of course we have to worry about how the sauce flows, but what Drs. Yeo and Friend have done here is use the physics of tossing dough to design SWUMS—standing wave ultrasonic motors. The motors are only about 250 µm wide and could travel through blood to take on dangerous bodily intruders one-on-one.

If you think these two have done enough research, you haven't been reading the New Scientist. In this NS online article, Dr. Yeo explains how his group has used surface acoustic waves to create a type of earthquake on a microchip. The earthquake converts the drug into an extremely fine mist that can then be absorbed quickly through the skin into the bloodstream. The research article appeared in Lab on a Chip.

Oh yeah, and there's this super cool video too:

In an earlier entry (Tiny Bubbles), I mentioned the idea of creating logical circuits by using nanoliter droplets through a microchannel. Microfluidics and circuits use similar terminology; notably "active" and "passive." An active electronic circuit draws power (usually for an operational amplifier) to shape a signal, whereas the passive circuit can be used without a power source. The advantages of the passive unit are low cost, zero power consumption, and long-term stability. Active components efficiently shape a signal, but at a cost of requiring a power supply.

Turning back to microfluidic devices; passive components have much the same advantages as passive circuitry: easy and cheap to fabricate and maintain, and more reliable and consistent performance. Because they're cheaper to produce, the possibility of a disposable lab-on-a-chip, or μTAS (Micro-Total Analysis Systems), device is more feasible.

More specifically, the passive microvalve has proven a valuable little invention. These valves can be as simple as a rubber flap (loosely speaking), but one chip could contain thousands. In addition to valves, passive versions of micropumps, -mixers, -dispensers, and -filters are used in increasingly complex microfluidic devices.

The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them. —William Bragg

I think Bragg would be excited about these types of biomicrofluidic advances. Delving further into the circuit/microdevice analogy seems worthwhile, considering the wealth of devices that are based on complex arrangements of simple circuits. How will scientists stretch this comparison further?

Will these passive components be responsible for a future torrent of advancement in the field of disease detection in third world countries? I would imagine that they will and more. There'll be an increasing number of advances in micro- and nanomechanical sensors for environmental, chemical, and biological detection as well. In addition to giving scientists new avenues for detection, the device opens up all sorts of opportunities for epidemiologists to study how a certain strain of a disease moves through a population or how a chemical spill spreads throughout a region, for example.

Singapore scientists have developed the best lab on a chip yet—one that detects avian flu (H5N1) and gives results in under 30 minutes. At the heart of the chip is a new more efficient method of analyzing RNA, which will eventually lead to other quick tests such as those for HIV, SARS, and Hepatitis B.

Here, there are two fascinating stories rolled into one: the first is an epidemiological breakthrough and all of the implications it may have on predicting or preventing a future pandemic. Current technologies take about 5 hours to test for H5N1, and looks to be at least 40 times cheaper. And forget trying to lug that kind of medical equipment to a remote or harsh climate in southeast Asia .

The microfluidics that the device employs integrates the entire workflow of viral RNA isolation, purification, preconcentration, and detection. Dr. Juergen Pipper, one of the researchers, explains:

The novelty of our method lies in the way that the droplet itself becomes a pump, valve, mixer, solid-phase extractor and real-time thermocycler. Complex biochemical tasks can thus be processed in a fashion similar to that of a traditional biological laboratory on a miniature scale.

The complex microfluidic device will hopefully be in production in time to bring solace to countries where a SARS outbreak poses a threat.

Microphysical devices are also offering solace from your lackluster golf game. Check out Sonic Golf's nifty training tool, which emits a pleasant tone when your club is swung correctly and an high-pitched annoying one when you're about to hook a golf ball into the woods. The real usefulness comes from receiving feedback the instant your swing goes awry, so you'll know exactly which part of your golf stroke needs adjustment. The device contains microelectromechanical systems (MEMS) that measure your swing's velocity and acceleration. The feedback mechanism created by the golfer and the device is what the device's inventor (Robert Grober, a Harvard physics professor) seems to think this is the key to mastering your stroke.

It is, of course, debatable which direction of research humanity should be most concerned about; improving golf scores or preventing global pandemics. For now, we get to have both.