Abstract

Design Principles For 3D-Printed Microfluidics

Noah Malmstadt, Professor of Chemical Engineering and Materials Science, University of Southern California

As 3D printing replaces traditional clean room manufacturing for microfluidic engineering applications, it’s becoming clear that this transition offers not only lower cost and faster design iterations, but also new opportunities for fluidic routing and control that are only possible due to the inherent three-dimensional nature of these systems. Over the past several years, we have developed design principles that take advantage of this three-dimensionality, as well as demonstrating several applications that benefit from this approach.

Designing fluidic paths in three dimensions can be facilitated using standard finite element modeling tools for fluid simulations. For instance, we used a FEM fluid mechanics simulation to design and optimize a 3D flow-focusing junction for manufacturing lipid vaccine nanoparticles. In addition, modular 3D printed devices allow for the application of rules from circuit design. And the nature of 3D printing as an easily characterized manufacturing technique facilitates the statistical analysis of tolerances to predict operational ranges of microfluidic systems.

3D printing also presents materials opportunities and challenges for microfluidic applications. For instance, stereolithographic resins can often poison enzymatic reactions, limiting applications to biochemical processing. We have explored surface modification techniques to passivate 3D-printed channel surfaces and enable on-chip enzymatic reactions.