By creating easy to snap together components, a team of scientists at the University of Southern California Viterbi School of Engineering, Los Angeles, say that it is now possible to build a 3D microfluidic system quickly and cheaply. Microfluidic systems are used to precisely manipulate small volumes of fluids, and are typically built in a cleanroom using the same technology developed to produce integrated circuits for the electronics industry.
Though the systems are tiny, designing, assembling, and testing a new microfluidics system can take a lot of time and money. Building a single device can often require multiple iterations, each of which can take up to two weeks and several thousand dollars to manufacture. And the more complex the system, the higher the number of iterations needed.
The team set out to simplify the construction process by separating basic microfluidic functions into standardized modular components. In microfluidics, they explained, they are concerned with the way fluids are routed, combined, mixed, and analyzed.
Borrowing an approach from the electronics industry, which uses prototype boards to build circuits, they imagined the 3D modular components that encapsulate the common elements of microfluidic systems, as well as a connector that could join the separate components together, ultimately designing computer models for eight modular fluidic and instrumentation components (MFICs) that would each perform a simple operation. The team’s development of these MFICs represents the first attempt to break a device into separate components that can be assembled, disassembled and re-assembled over and over.
Using 3D-printed MFICs, in a matter of hours the team was able to build and test a device that mixed fluids using a helix component and turned the mixture into droplets. Essentially a very long track packed into the same standardized module footprint, the helix component allows adjustments in flow resistance or can serve as an efficient mixer. In microfluidic systems, mixing is dominated by diffusion, and a complex helix can speed up the process by folding the fluid onto itself.