Rapid prototyping of cyclic olefin copolymer (COC) microfluidic devices

We introduce a low-cost, high yield rapid fabrication method for casting COC microfluidic chips that is appropriate for academic labs and small companies. Devices are comprised of two molded pieces joined together to create a sealed device. The first piece contains the microfluidic features and the second contains the inlet and outlet manifold, a frame for rigidity and a viewing window. The microfluidic features are patterned using a PDMS mold that itself was replica-molded from a photoresist master. Dimensional stability of the microfluidics portion of the COC device is achieved by confining the PDMS mold in an aluminium frame. The mold for the lid is CNC milled from aluminium. Sealing the COC device is accomplished by timed immersion of the lid in a mixture of volatile and non-volatile solvents followed by application of heat and pressure. Surface treatment to render the device fluorophilic is performed using dopamine in assembled devices.