2.3 Assembly
For a single microfluidic chip, 1 vinyl sheet with design B and 20
sheets with design A are overlapped to create a final single piece of
vinyl 1500 μm thick, which sets the depth of the microfluidic device.
Afterward, this piece is stuck onto a glass slide. To avoid leaks
between vinyl and glass, pressure and temperature are applied to the
piece (47 KPa, 80°C). To complete the assembly process, the chip is
sealed with a PDMS block. The PDMS block must be previously cleaned with
isopropanol and exposed to an oxygen plasma treatment (50 Watts, 120”)
to hydrophilize the surface which is essential to seal the PDMS with the
vinyl. After the plasma treatment the PDMS block is placed above the
vinyl and the glass slide and the complete chip is assembled. This
monolithic chip is reusable and autoclavable.