Abstract

3D Printing in Microfluidics

Rosanne Guijt, Senior Lecturer, University of Tasmania

Over the past 5 years, 3D printing applications penetrated the laboratory-based sciences for the fabrication of customised parts. Enhancements in resolution have made 3D printing an attractive alternative for the manufacture of microfluidic devices. Inkjet printing, fused deposition moulding (FDM), and stereo lithography (SL) are the 3D printing approaches most commonly used in microfluidics. Inkjet (or polyjet) 3D printers work by spraying a resin followed by crosslinking through exposure to UV light. In FDM, a thermopolymer is extruded through a heated nozzle and deposited onto a build platform, During SL, a resin is crosslinked in areas defined by a digital light projector or by rastering with a laser beam. All three are additive manufacturing techniques, where geometries are deposited the xy plane, followed by a movement along the z-axis before the addition of the next layer. The performance of inkjet printing, FDM and SL for microfluidics is compared based on resolution, accuracy, cost, material choice and fluidic behaviour. In addition to the creation of complex, 3D fluidic structures, functionality can be added using different materials. FDM has the widest range of materials, and was used to create a complex microfluidic device containing integrated membranes and electrodes for the electrokinetic extraction, concentration and separation of small molecules.