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Microfluidic devices are constructed from a translucent, gas-permeable polymer and bound to a glass coverslip, which allows for observation using fluorescence microscopy. Polydimethylsiloxane (PDMS) is gas permeable, and has the unique property of having the same optical properties as water, which simplifies imaging of aqueous systems(Ferry, Razinkov, and Hasty 2011).
Mixing PDMS
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