Modular Microfluidic PDMS Blocks Using a Magnetic Connection System

A modular microfluidic system is presented which can be used to easily and individually build a microfluidic network by linking different modules. We report on a fabrication technology based on polydimethylsiloxane (PDMS) microfluidic blocks, where channel structures and shapes are 3D-printed using acrylonitrile butadiene styrene (ABS). These templates are then put into a polyurethane (PU) mold and, after casting of the PDMS, dissolved using acetone. By applying this process, a big variety of channel designs can be realized. Sensors, valves and other components could be easily integrated, by placing them into the mold before casting of the PDMS. A suitable arrangement of embedded permanent magnets at the fluidic interfaces of the modules enables an easy and flexible linking and delinking of modules with each other. In combination with an O-ring-like structure on the connection surfaces, the fluidic interconnection between the blocks is self-sealing for difference pressures up to 130 kPa. Moreover, the fabricated blocks are optically transparent and chemically inert.