Lamination-based rapid prototyping of microfluidic devices using flexible thermoplastic substrates

Transposing highly sensitive DNA separation methods (such as DNA sequencing with high read length or the detection of point mutations) to microchip format without loss of resolution requires fabrication of relatively long (approx. 10 cm) microchannels along with sharp injection bands. Conventional soft lithography methods, such as mold casting or hot‐embossing in a press, are not convenient for fabricating long channels. We have developed a lamination‐based replication technique for rapid fabrication of sealed microfluidic devices with a 10 cm long, linear separation channel. These devices are fabricated in thin cyclo‐olefin copolymer (COC) plastic substrates, thus making the device flexible and capable of assuming a range of 3‐D configurations. Due to the good optical properties of COC, this new family of devices combines multiple advantages of planar microfluidics and fused‐silica capillaries.