Microfluidics



Microfluidics refers to a set of technologies that control the flow of minute amounts of liquids or gases — typically measured in nano- and picoliters — in a miniaturized system.

Just as a computer chip has carefully-arranged wires that electricity moves around, a microfluidic chip has tiny channels etched onto it that fluids move around. In a biochemistry laboratory, a chemist might pipette some solution out of a flask, mix it with a reagent, fractionate it, or perform other operations on it. The interesting thing is that most of these processes are just a matter of moving liquids around, so they can be replicated with microfluidics. The advantage is that microfluidics is much cheaper, safer and requires less skill. Room-sized diagnostic testing equipment can be shrunk down to the size of a postage stamp. This is also called "lab-on-a-chip".

Applications are as vast as they are revolutionary, and include -
 * Medical diagnostics and blood tests
 * Medical and chemical research - testing for genes, chemical separation and reactions
 * Environmental sensing - testing water quality, air quality, monitoring for environmental toxins
 * Testing for plant diseases
 * Testing soils (biosensor example here)
 * mining
 * developing biofuels
 * and many more.

Microfluidics in Open Source Ecology
We are interested in very cheap, open-source ways of making microfluidic chips. There are plenty of groups working on this; it's a matter of gathering the information.

DIY microfluidics methods

 * How to make a microfluidic chip using double-sided sellotape, glass slides and a scalpel: . This requires inlet and outlet holes in the slide; perhaps these could be made with a laser cutter?
 * Complex 3D microfluidic devices made with alternating layers of paper and double-sided tape: . The tape was cut using a laser cutter. The paper was treated with photoresist (a light-sensitive polymer) and exposed to UV light when masked with a transparency with a pattern printed onto it. Cost of fabricating a chip = $0.03.
 * Disposable microfluidic devices created using regular wax paper
 * Shrinky Dink® microfluidics - academic paper here

Channel designs
Are there online repositories of channel designs for different purposes?

Micado is open-source software for designing microfluidic chips.

Materials and Equipment Used
Consumables:
 * blotter paper
 * regular paper
 * wax paper, shrinky-dink
 * transparency film
 * cotton thread
 * sewing needles
 * wood sticks
 * Jell-O
 * beeswax?

Equipment:
 * syringes
 * cell phone cameras
 * plastic lenses for cheap microscopes
 * Laser cutter, see Low-cost rapid prototyping of flexible microfluidic devices using a desktop digital craft cutter

George Whitesides, Harvard University
In his legendary career in chemistry, George Whitesides has been a pioneer in microfabrication and nanoscale self-assembly. Now, he's fabbing a diagnostic lab on a chip.

   <param name="flashvars" value="vu=http://video.ted.com/talks/dynamic/GeorgeWhitesides_2009X-medium.flv&su=http://images.ted.com/images/ted/tedindex/embed-posters/GeorgeWhitesides-2009X.embed_thumbnail.jpg&vw=432&vh=240&ap=0&ti=760&introDuration=15330&adDuration=4000&postAdDuration=830&adKeys=talk=george_whitesides_a_lab_the_size_of_a_postage_stamp;year=2009;theme=what_s_next_in_tech;theme=design_like_you_give_a_damn;theme=rethinking_poverty;theme=a_taste_of_tedx;theme=tales_of_invention;event=TEDxBoston+2009;&preAdTag=tconf.ted/embed;tile=1;sz=512x288;" /><embed src="http://video.ted.com/assets/player/swf/EmbedPlayer.swf" pluginspace="http://www.macromedia.com/go/getflashplayer" type="application/x-shockwave-flash" wmode="transparent" bgColor="#ffffff" width="446" height="326" allowFullScreen="true" allowScriptAccess="always" flashvars="vu=http://video.ted.com/talks/dynamic/GeorgeWhitesides_2009X-medium.flv&su=http://images.ted.com/images/ted/tedindex/embed-posters/GeorgeWhitesides-2009X.embed_thumbnail.jpg&vw=432&vh=240&ap=0&ti=760&introDuration=15330&adDuration=4000&postAdDuration=830&adKeys=talk=george_whitesides_a_lab_the_size_of_a_postage_stamp;year=2009;theme=what_s_next_in_tech;theme=design_like_you_give_a_damn;theme=rethinking_poverty;theme=a_taste_of_tedx;theme=tales_of_invention;event=TEDxBoston+2009;">