Measurement of Budding Yeast Growth Rate With MOSFET-Based Microfluidic Coulter Counters

Abstract

Many bioassays are performed on an ensemble of cells and assay results depend crucially on the state of cells relative to one another. If the cells in the ensemble are disordered with respect to one variable, then the measurements that depend on that variable are confounded by averaging. One solution to this is to maintain the cell cycle synchrony for the cells in the ensemble. To do this, it is extremely important to accurately measure the cell growth rate. For example, the volume growth rate of budding yeast is closely linked to many aspects of the cell cycle. Therefore, investigation of the volume growth rate of budding yeast has become an appealing research topic because of its important implications in achieving cell cycle synchrony. In this paper, we report on applications of novel microfluidic sensing technique to measure the volume growth rate of individual budding yeast. We apply our recently developed MOSFET-based microfluidic Coulter counters to detect the volume of budding yeast when it is translocated through the sensing aperture forth and back, controlled by adjusting the direction of electroosmotic flow inside the microfluidic device. Our results indicate that because of the enhanced sensitivity of the MOSFET-based microfluidic Coulter counter, it is possible to measure the volume growth rate of individual budding yeast over its whole cell cycle. The measurement results clearly showed the volume growth of the individual budding yeast.