Thermal bubble-driven impedance-based high-throughput cell counting chip design

Abstract

Cell identification and enumeration are important methods within clinical and research laboratories for rapid diagnosis of relevant diseases. However, there are still many shortcomings in the current cell counting methods. In order to improve the performance of cell counting, a novel impedance-based cell counting chip based on thermal bubble drive was designed in this study. The chip is fabricated by whole-wafer processing and provides the driving force for cells through a combination of thermal bubble nozzles and microfluidic channels, integrating 100 individual detection units on a 38 mm2 size chip. Experimental and theoretical analyses have demonstrated that the chip can achieve high throughput detection of 45 000 beads/s under extreme conditions. A fourfold difference in detection voltage was obtained for both 14 and 7 µm diameter polystyrene beads. The linear fit coefficient of determination between the cell number measured by the chip and the cell number observed in reality was above 0.999 for both polystyrene beads and 211H cells, and the counting accuracy exceeded previous studies. It turns out that the chip achieves portable, low-cost, high-throughput, and high-accuracy cell counting, which is conducive to the development of impedance cell counting.