Fabrication of microfluidic devices based on glass–PDMS–glass technology

We describe an alternative technology for the fabrication of microfluidic devices having a glass–PDMS–glass sandwich configuration. The advantage of this technique relies on the use of a patterned PDMS layer as both a bonding layer and a working layer for lateral fluid confinements. Conventional lithography, etch and lift off techniques can be easily applied to both glass substrates, which enhances patterning capabilities of top and bottom surfaces of microchannels. The detailed fabrication process is presented and discussed. The performance of the fabricated devices is also illustrated through the measurement of electro-osmotic flows in microfluidic channels coated with different materials.