April 2021
Vol 7, Issue 16

About The Cover

Cover image expansion

ONLINE COVER While particle sorting is essential for medical research and for determining the ages of rocks, fossils, and sediments, existing technologies are not suited for large-scale sorting of particles greater than 100 micrometers in size. To overcome this barrier, Kasai et al. developed a novel on-chip sorting method which leverages moving vortices generated by micro-jet flows. The technology is activated through fluorescence detection. The researchers successfully used the novel method to sort 160-micrometer microbeads and purified fossil pollen from lake sediments at a frequency of 2.9 kilohertz, from which they were able to obtain accurate radiocarbon dates. They determined that this method has a 15-times higher sorting performance than the latest state-of-the-art sorter and conclude that it may serve a variety of large-particle applications in biological and medical research, such as sorting cell-containing droplets in genomics or cell spheroids in regenerative medicine. Additionally, Kasai et al. note that the new sorter offers opportunities to apply particle sorting in new fields, including geochronology, paleoecology, and paleoclimatology, by purifying pollen, diatoms, microalgae, and other microfossils. [CREDIT: YUSUKE KASAI AND SHINYA SAKUMA]