Typically, microchips used for mass spectrometry analysis at the university are prepared in large batches in the cleanroom, and researchers often get stuck waiting for the full batch to be ready before they can proceed with their work. Dr. Gianmario Scotti and Markus Haapala had a better idea, though – what if they could skip the cleanroom phase altogether by fabricating a small, disposable container that could be connected to a mass spectrometer for chemical reaction analysis?
“I had been working with the 3D printing of stainless steel, so 3D printing was an obvious choice for the fabrication method,” said Dr. Scotti. “But 3D printing of steel is not very economical, so we decided to stay with plastics.”
Finding a plastic material that wouldn’t be damaged by the solvents used in chemical reaction tests was a bit difficult, however. The researchers decided that polypropylene would be perfect, thanks to its high chemical resistance, but although it’s one of the most commonly used plastics in the world, it’s difficult to 3D print and thus tough to find as a 3D printing material. Dr. Scotti finally found a supplier in Germany, however, and they began prototyping until they had a 3D printed microreactor.
Then it was time to test the microreactor with an actual mass spectrometer, which is fellow researcher Sofia Nilsson’s area of expertise.
The 3D printed microreactor worked just as well with the mass spectrometer as a standard microchip would, if not better – and there’s now no need to wait for a full batch of microchips to be prepared.“By hooking up a microreactor to a mass spectrometer, reactions can be followed in real time with high sensitivity and selectivity,” said Nilsson. “Thanks to this, it’s possible to detect intermediates and even transition states of reactions, making the stipulation of a reaction mechanism possible, which is what my research is focused on.”
The research team documented their work in a paper entitled “A miniaturised 3D printed polypropylene reactor for online reaction analysis by mass spectrometry,” which you can access here. The paper’s authors include Gianmario Scotti, Sofia M.E. Nilsson, Markus Haapala, Päivi Pöhö, Gustav Boije af Gennäs, Jari Yli-Kauhaluoma and Tapio Kotiaho. Discuss in the Microreactor forum at 3DPB.com.
[Source: University of Helsinki]