A low-cost 3D-printing based rapid fabrication procedure for modular microfluidic platform

Abstract This paper introduces a low-cost, rapid, simple method for fabricating 3D-printed microfluidic chips with inspiration from LEGO® bricks to accommodate modular microfluidic platforms. A fused filament fabrication 3D printer was operated and modified to print a single 400µm layer of thermoplastic material onto a polymethyl methacrylate substrate, resulting in a very smooth and transparent microchannel by eliminating the limitations of this additive manufacturing. Specific male/female chip-to-world and chip-to-chip connectors have been developed to implement the device's modularity. In addition, various post-processing procedures were considered because of the inherent surface roughness of the fused filament fabrication method. Furthermore, several bonding methods have been tested and utilized to attach different layers of microfluidic chips. Several microfluidic components were designed and fabricated, including T-shaped and cross-shaped microchannels, zig-zag pattern micromixers, and four oval-shaped parallel microchannel. The chips' validity was examined by injecting food dye into a group of modules to observe the chips' leakage and fluid circulation behavior. At last, a fluorescent test was implemented to observe the mixing efficiency of the micromixer chip. The proposed fabrication method, from materials’ cost, accessibility, and commercialized perspectives, offers high throughput process. In other words, it could be fabricated and implemented in most lab environments with limited facilities and budget without the necessity for expensive equipment. All microfluidic chips in this work have been designed using a modular concept, a relatively new approach in microfluidics that allows users to reconfigure connections and microfluidic components to obtain the desired system.