Abstract

Advanced 3D Printing for Microfluidics

Gregory Nordin, Professor, Brigham Young University

While there is great interest in 3D printing for microfluidic device fabrication, a main challenge has been to achieve feature sizes that are in the truly microfluidic regime (<100 µm). The fundamental problem is that commercial tools and materials, which excel in many other application areas, have not been developed to address the unique needs of microfluidic device fabrication, which focus on negative space features. Consequently, we have created our own stereolithographic 3D printers and materials that are specifically tailored to meet these needs. We have shown that flow channels as small as 18 µm x 20 µm can be reliably fabricated, as well as compact active elements such as valves and pumps. With these capabilities, we demonstrate highly integrated 3D printed microfluidic devices such as a 10-stage 2-fold serial dilutor that simultaneously creates a 3 order of magnitude range of concentrations, and high density chip-to-chip interconnects (53 interconnects per square mm) that are directly 3D printed as part of a device chip. These advances open the door to 3D printing as a replacement for expensive cleanroom fabrication processes, with the additional advantage of fast (~5-10 minute), parallel fabrication of many devices in a single print run due to their small size.