Discoveries made by FNP programme winners, featured in Nature Communications

25 July 2019

"FNP programme winners, in cooperation with Dutch and Australian researchers, have discovered a new model of droplet formation in microfluidic channels. The article is the result of work under the FIRST TEAM grant programme of the Foundation for Polish Science, led by Dr hab. Piotr Korczyk of the Institute of Fundamental Technological Research, Polish Academy of Sciences, and showcases cooperation with another FNP project leader ? Prof. Dr hab. Piotr Garstecki, responsible for the TEAM-TECH project implemented by Bacteromic Sp. z.o.o. The results have been published in Nature Communications. A research team composed of the Polish Academy of Sciences, Delft University of Technology and University of South Australia scientists examined the process of droplet formation in a perpendicular intersection of two several-hundred micrometer wide inlet channels. The crossing of the flows of two immiscible liquids in such configuration leads to a spontaneous and extremely reproducible droplet formation. This method is commonly used in droplet microfluidic systems. An interesting aspect of the preliminary experiments was the incompatibility of the observations with the existing knowledge on the mechanisms governing droplet formation. In order to explain these surprising observations, the researchers created a new mathematical model of the mechanism of droplet formation, taking into account the flows around droplets that had not been previously considered. This study identified a new droplet formation regime and presented a model of droplet formation process that covers all regimes, depending on the significance of surface tension and shear, and flow in a limited microchannel space. The study significantly expands our knowledge of the mechanisms occurring in two-phase flows in microchannels. The small size of such systems makes the surface tension the dominant factor, leading to fascinating and often counter-intuitive effects. Precise control over the formation of small droplets of the desired size is essential for the development of microflow techniques and breakthrough research solutions in biochemical analysis, with applications such as single cell sequencing. Further reading