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Background and Objective: Single-cell electrical properties(e.g.,specific membrane capacitance(Cspecific membrane))are important label-free biophysical markers for cell status evaluation[l].Previously,we developed a microfluidic system capable of characterizing Cspecific membrane from hundreds of single cellsc2],which,however,requested large cell numbers(quantification of hundreds of cells needs 1 ml cell solution with the concentration of le6 cells per ml).This study aims to propose a new microfluidic platform enabling single-cell Cspecific membrane characterization with decreased cell number requirement.Method: As shown in Figure(a),a T-shape microfluidic device was proposed,which is composed of a cell loading channel,a cell collecting channel and a constriction channel in between.In experiments,a positive pressure was applied at the channel inlet to load cells and a negative pressure was applied at the outlet 2 to aspirate cells through the constriction channel with cell elongation and impedance data quantified and translated to Cspecific membrane and Dcell.Results and Conclusion: Compared to the collected cell numbers of 19.8+13.6 cells per 150 sec based on the previous system at the cell concentration of le6 cells/mlc2],the current system was shown to have a throughput of 11.0+5.5 cells at the cell concentration of le5 cells/ml,an order improvement in throughput(see Figure(b)).Furthermore,comparable values of Cspeciric membrane(1.63±0.52 vs.1.57+0.31 μF/cm2)and DceU(14.4±1.3 vs.14.8±0.9 μm)were obtained by the previous system(n=489)at le6 cells/ml and the current system(n=190)at le5 cells/ml,respectively.These results indicate that the current system has the ability to collect single-cell electrical properties with a lower demand on total cell numbers.