(349c) Microfluidic Micropipette Aspirator for Large-Scale Mechanical Characterization of Cells

Recent advances in microfluidics have led to high throughput methods for mechanical characterization of thousands of individual cells. These techniques use shear and extensional flows to expose cells to large strain rates (> 1000 s^-1) and use the deformed cell shape as a measure of cell mechanics. Importantly, these methods characterize cellular mechanical properties at a single time point precluding understanding of how cells temporally modulate their mechanics in response to environmental cues. In this study, we report a microfluidic analog of micropipette aspiration that allows measurement of mechanical properties of thousands of cells in few minutes. This capability is enabled by a novel microfluidic network design that allows capture of individual cells at prescribed locations and subjecting each cell to nearly identical hydrodynamic stresses. We test the device with cancer cells and quantify their linear and nonlinear rheology. By applying models that have been used in the micropipette aspiration literature, we characterize the cortical tension and Young’s modulus of individual cells. Using blebbistatin which inhibits actomyosin contractility, we find that cortical tension and Young’s modulus is reduced. Using paclitaxel which stabilizes microtubule network, we measure higher cortical tension and modulus. We will further discuss how our approach can be used to characterize time-dependent variations in cell mechanics in response to drug treatment.