Cell-Deformability-Monitoring Chips Based on Strain-Dependent Cell-Lysis Rates

We present a novel cell-deformability-monitoring chip based on the digitally measured cell-lysis rate which is dependent on the areal strain of the cell membrane. This method offers simple and automated cell-deformability monitoring based on the mechanical property of the cell membrane. We suggest a filter design that considers the areal strain imposed on the cell membrane passing through the filter array with a gradually increased orifice length. In the experiment using erythrocytes, we characterized the cell deformability in terms of the average fracture areal strains that were 0.24 plusmn 0.014 and 0.21 plusmn 0.002 for normal and chemically treated erythrocytes, respectively. We also verified that the areal strain of 0.15 effectively discriminates the deformability difference of the normal and chemically treated erythrocytes. We compared the lysis rates and their difference for the samples from different donors and found that the patient-specific difference is negligible. However, the additional work on clinical demonstration is required to apply the present chips to the diagnostics. The experimental results demonstrate the simple structure and high performance of the present cell-deformability-monitoring chips, which are applicable to simple and cost-effective cell-aging-process monitoring.