Effective concentration of marine nanoflagellates with a microfluidic device

Abstract

Protist cells are typically manipulated through either centrifugation or membrane filtration, which can damage these fragile cell types. Use of microfluidic devices could greatly aid in the separation and concentration of protist cells with significantly less damage. Recent developments have enabled passive cell separation and consequent concentration based only on cell size. We utilize these advances to show that a passive spiral microfluidic device can effectively concentrate marine nanoflagellates within the 3-20 micron size range without harm to cells, while reducing background bacteria levels. The ability to concentrate these cell types appears only dependent on cell size, despite complicated cell surface geometries and motility. We anticipate that this approach will greatly aid researchers who require an ability to manipulate fragile cell types as well as reduce bacteria concentrations for experimental setups and cell isolation.