High throughput cell stiffness measurement via multiplexed impedance sensors.

Since physiological and pathological events change the mechanical properties of cells, tools that rapidly quantify such changes at the single-cell level can advance the utility of cell mechanics as a label-free biomarker. We demonstrate the capability to probe the population-level elastic modulus and fluidity of MDA-MB-231 cells at a throughput of up to 50 cell/second within a portable microchip. Our sensing scheme adapts a code multiplexing scheme to implement a distributed network of sensors throughout the microchip, thereby compressing all sensing events into a single electrical output. To validate our approach, we prepared cell samples whose stiffnesses were manipulated with chemical agents. We confirmed the expected effect of the chemicals agreed with the stiffness measurements reported by our microchip. Such a low-cost electronic assay that rapidly measures mechanical properties enables previously infeasible studies to advance the science of mechanobiology.