Mechanical Characterization of Cells and Microspheres Sorted by Acoustophoresis with In-Line Resistive Pulse Sensing

Resistive pulse sensing (RPS) is a key label-free technology to measure particles and single-cell size distribution. As a growing corpus of evidence supports that cancer cells exhibit distinct mechanical phenotypes from healthy cells, expanding the method from size to mechanical sensing could represent a pertinent and innovative tool for cancer research. In this paper, we infer the cells' compressibility by using acoustic radiation pressure to deflect flowing cells in a microchannel, and use RPS to sense the subpopulations of cells and particles at each acoustic power level. Compared to current acoustic cell phenotyping apparatus based on video cameras, the proposed approach is not limited by optical diffraction, frame rate, data storage, or processing speed, and may ultimately constitute a step forward towards point-of-care acousto-electrical phenotyping and acoustic phenotyping of liquid biosamples.