Thermoplastic Microfluidics

Thermoplastic polymers are besides glass the material of choice for the industrialization of microfluidic and organ-on-chip applications. In most cases, however, such devices are developed on the basis standard lithographic clean room technologies and subsequent casting into PDMS. This results in comparably fast progress in the development of functional designs but important aspects with respect to later industrialization are thereby largely neglected. For that reason, it is advisable to switch at a rather early stage of development from PDMS to a thermoplastic polymer such as, for instance, cyclo-olefin (co)polymer (COC, COP). By making this step, additional challenges related to the anticipated manufacturing process can be identified, which is particularly important when aiming at industrialization. We present herein a standard process sequence for mastering of microfluidic devices by two-photon polymerization and final transfer into COC films by hot embossing. In addition, we describe the laser micromanufacturing of polymeric mold inserts and subsequent prototype injection molding of small series of COP samples.