DOE’s Lawrence Berkeley National Laboratory has just developed a liquid printed chip that can reconfigure itself at the click of a button, thus serving multiple applications by altering its internal make-up. The liquid chip could serve functions as diverse as synthesising battery materials or screening drug candidates. It can thus serve as a multi-functional, multi-material ‘lab on a chip’.
The researchers fabricate this tiny programmable liquid chip using liquid printing. With a mixture of hydrophilic and hydrophobic substances, they were able to create micropatterns with custom-purposed geometries. As a result, when aqueous solutions run through microchannels with different widths, and are taken out by external pumps operating simultaneously, the chip achieves chemical flow through the entire structure.
“What we demonstrated is remarkable. Our 3D-printed device can be programmed to carry out multistep, complex chemical reactions on demand,” said Brett Helms, a staff scientist in Berkeley Lab’s Materials Sciences Division and Molecular Foundry, who led the study. “What’s even more amazing is that this versatile platform can be reconfigured to efficiently and precisely combine molecules to form very specific products, such as organic battery materials.”
Microfluidics 3D Printing
Creating microfluidics is a key component of many fields such as medicine or pharmacology. Thus, the devices are very versatile and function with a range of chemical reactions. This gives them the various, seemingly contradictory functions the liquid chip can embody. The device has multiple channels that create a very specific order for the chemical reactions to happen as they flow through. This requires some delicate, nano-scale resolution on part of the printer. Similarly, as this process acts like a circulatory system when separating molecules and cleaning them, it can also be useful for pharmaceutical purposes.
“The form and functions of these devices are only limited by the imagination of the researcher,” explained Helms. “Autonomous synthesis is an emerging area of interest in the chemistry and materials communities, and our technique for 3D-printing devices for all-liquid flow chemistry could help to play an important role in establishing the field.”
To create the programmable liquid chip, lead author and post-doctoral researcher Wenqian Feng designed a custom-pattern glass substrate. Two liquids, one containing nanoscale clay particles and another containing polymer particles, were printed onto the substrate. These both reform at within milliseconds, becoming a very thin channel or tube about 1mm in diameter.
For this process, the researchers used a Cellink Inkredible+ 3D Printer with a 14-gauge dispense tip as a print-head. They printed out clay dispersions in silicone oil to generate ‘3D aqueous threads’, using a Python script for G-code. Next, they plan to electrify the walls of the liquid chip in further experiments down the line. This may allow them to explore various other applications in “all-liquid circuitry, fuel cells, and even batteries”
Featured image courtesy of Berkeley Laboraties. The full study is also available here.