Whether you say ‘lay-go’, ‘leg-oh’, or ‘lee-go’, we can all agree that LEGO is pretty awesome. My childhood was filled with LEGO houses and castles, tower building competitions, and shredded fingernails from trying to prise apart small plates (did you know they have a tool for that now?). One of the best things about LEGO is that you can create almost anything, from giant sculptures to a working mechanical keyboard.
But who knew LEGO could be so versatile that it could be used to build a tiny microfluidics lab?
Microfluidics is basically the manipulation of fluids on a really small scale. With microfluidics, we can move, mix, separate fluids. This can be used for things like enzymatic analysis, DNA sequencing, continuous testing for pathogens or toxins, and many other biological, optical and chemical applications.
To play with microfluids, we need a ‘lab on a chip’ – a tiny, flat surface etched with channels and ports to manipulate the flow, mixing, and separating of the fluid. However, there’s no universally accepted way to construct this device. Therefore, researchers need to synthesise each chip for its particular purpose. This makes it hard to mix and match devices. On top of that, the chips are not easy to make as 3D printing is not yet precise enough while it usually requires expensive facilities, materials and labour.
An alternative method is to build a modular system, with each module performing a single function. And scientists at MIT have found a novel platform: LEGO bricks.
In their recent paper, published in Lab on a Chip, Crystal Owens and John Hart explored the use of LEGO bricks to build a microfluidic platform. They went out to the store, bought an off-the-shelf LEGO set, and used a tiny drill to precisely etch channels into the bricks. To seal the faces, the bricks were covered in a thin plastic film, and brick modules were joined via an O-ring. Because LEGO bricks are so consistent in size and fit together easily, the O-rings formed reliable and reversible seals that allow the microfluidic device to be literally ‘clicked’ together.
While this system is cheap to build and extremely reliable, it is not perfect yet. Firstly, the micromilled channels are relatively large and not suitable for all applications. They’re also made of plastic so they are soluble and therefore not compatible to use with some organic solvents. Future research will look into the different types of materials and ways of constructing the bricks so they can be used for a wider range of applications. But for now, a LEGO ‘lab on a brick’ could be the future of prototyping these tiny microfluidic devices.