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# Microfluidics projects overview #
low-cost and open source microfluidic chip for DNA synthesis and probably DNA sequencing, thermocycling, cell culture, transgenics/electroporation, bubble logic, etc.
## Strategy ##
probably 2-layer PDMS with pressure valves
## Equipment ##
* mini laser cutter (1 micron beam width, approx. 1 micron step size)
* dust fan for cutting fumes
* syringe pumps
* spin coater
## Testing ##
Microfluidics are often tested by flowing dyes and fluorescent beads.
* anionic (- charge)
* cationic (+ charge)
### Food Coloring ###
Name | Characteristics | Image of molecule
--- | --- | ---
[Tartrazine (FD&C Yellow 5)](https://en.wikipedia.org/wiki/Tartrazine) | anionic. hydrophilic azo dye, maximum absorbance in an aqueous solution at 425 nm. | 
[Indigo carmine (FD&C Blue 2)](https://en.wikipedia.org/wiki/Indigo_carmine) | anionic. pH indicator, Indolesulfonic acid, Indigo carmine in a 0.2% aqueous solution is blue at pH 11.4 and yellow at 13.0. Indigo carmine is also a redox indicator, turning yellow upon reduction. | 
[Fast Green FCF (FD&C Green 3)](https://en.wikipedia.org/wiki/Fast_Green_FCF) | mixed cat/anionic. It is used as a quantitative stain for histones at alkaline pH after acid extraction of DNA. It is also used as a protein stain in electrophoresis. Its absorption maximum is at 625 nm. | 
[Erythrosine (FD&C Red 3)](https://en.wikipedia.org/wiki/Erythrosine) | anionic. It is the disodium salt of 2,4,5,7-tetraiodofluorescein. Its maximum absorbance is at 530 nm in an aqueous solution, and it is subject to photodegradation. | 
[Brilliant Blue FCF (FD&C Blue 1)](https://en.wikipedia.org/wiki/Brilliant_Blue_FCF) | mixed, looks mostly anionic. It is soluble in water, and the solution has a maximum absorption at about 628 nanometers. | 
[Allura Red AC (FD&C Red 40)](https://en.wikipedia.org/wiki/Allura_Red_AC) | anionic. in solution, its maximum absorbance lies at about 504 nm. | 
[Sunset Yellow (FD&C Yellow 6)](https://en.wikipedia.org/wiki/Sunset_Yellow_FCF) | anionic. pH dependent azo dye with a maximum absorption at about 480 nm at pH 1 and 443 nm at pH 13 with a shoulder at 500 nm. | 
### Common Biotech Dyes ###
Name | Characteristics | Image of molecule
--- | --- | ---
[Crystal Violet](https://en.wikipedia.org/wiki/Crystal_violet) | cationic? When dissolved in water, the dye has a blue-violet colour with an absorbance maximum at 590 nm and an extinction coefficient of 87,000 M−1 cm−1. The colour of the dye depends on the acidity of the solution. At a pH of 1.0, the dye is green with absorption maxima at 420 nm and 620 nm, while in a strongly acidic solution (pH of −1), the dye is yellow with an absorption maximum at 420 nm. | 
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