Inexpensive and rapid fabrication of PDMS microfluidic devices for biological testing applications using low cost commercially available 3D printers

Polydimethylsiloxane (PDMS) elastomers have been extensively used in the development of microfluidic devices, capable of miniaturizing biomolecular and cellular assays to the microlitre and nanolitre range, thereby increasing the throughput of experimentation. PDMS has been widely used due to its optical clarity and biocompatibility, among other desirable physical and chemical properties. Despite the widespread use of PDMS in microfluidic devices, the fabrication process typically via soft lithography technology requires specialized facilities, instruments, and materials only available in a limited number of laboratories. To expand microfluidic research capabilities to a greater scientific population, we developed and characterized a simple and robust method of fabricating relatively inexpensive PDMS microfluidic devices using readily available reagents and commercially available three-dimensional (3D) printers. The moulds produced from the 3D printers resolve designed microfluidic channel features accurately with high resolution (>100 µm). The critical physical and chemical post-processing modifications we outline here are required to generate functional and optically clear microfluidic devices.