Node-Pore Sensing for Characterizing Cells and Extracellular Vesicles.

Node-Pore Sensing, NPS, is an extremely versatile and powerful technique for the analysis of cells and the detection of extracellular vesicles (EVs). NPS involves measuring the modulated current pulse caused by a cell transiting a microfluidic channel that has been segmented by a series of inserted nodes. As the current pulse reflects the number of nodes and segments of the channel, NPS can achieve exquisite sensitivity. Thus, when used as a Coulter counter, NPS can measure the sub-micron size increase of antibody-coated colloids to which EVs are specifically bound. By simply inserting between two nodes a "contraction" channel through which cells can squeeze, one can mechanically phenotype cells. We discuss the details of performing these two NPS applications.