Microfluidics is an important field of study that deals with the manipulation and precise control of fluids at submillimeter scales using minute, 2D chips, popularly known as lab-on-a-chip. Each chip contains tiny ports and channels specially arranged to perform a range of operations such as sorting, mixing, storage and pumping of fluids as they flow through.
However, a major drawback of these chips lies in their rigorous and time-consuming production process. With the use of LEGO bricks, this limitation is set to give way.
Interlocking injection-molded (LEGO) blocks are produced with a high level of precision, consistency and modularity, which enables them to line up easily and snap in place securely when coupled. These qualities made them a perfect candidate to replace lab-on-a-chip.
In the design of the microfluidic setup, small fluid channels were micro-milled into the LEGO bricks such that the outlet of a piece fits perfectly with the inlet of the next brick. The walls of the bricks were then sealed with an adhesive, allowing for easy assembly and reconfiguration of modular units.
The bricks were designed with various patterns aimed at performing specific tasks such as mixing, droplet generation etc., which make it relevant to biological operations including fluid mixing, cell sorting and filtering out desired molecules.
The desired function is achieved by the shape and size of the channels micro-milled into the bricks. For instance, a “Y-shaped” channel allowed for fluid mixing by channeling different fluids through the arms of the “Y,” while a “T-shaped” channel allowed for droplet generation.
The major draw back of this process lies in the micro-milling technique, which can’t create channels smaller than tens of microns, whereas there are microfluidic operations that require much smaller channels. Also, LEGO bricks are produced from thermoplastics, which can’t withstand certain chemicals used in microfluidic operations.
This study was carried out by graduate student Crystal Owens and associate professor John Hart at MIT’s Department of Mechanical Engineering. The full details of their findings was published in the recent issue of the journal Lab on a Chip. The research was funded by a National Science Foundation Graduate Research Fellowship, 3M Faculty Award and MIT Lincoln Laboratory Advanced Concepts Committee, among others.
For more microfluid tech, check out Engineers Create World's Smallest Guillotine.