Automated Hemocytometer-Based Live/Dead Cell Counting

By Brad Larson, Ellaine Abueg, Leonie Rieger, and Peter Banks, Applications Department, BioTek Instruments, Inc.

Cell counting is one of the most common laboratory tasks in the life sciences. It is required for routine cell culture propagation and as a starting point for any cell-based assay. While there are many instruments available for automated cell counting, the reusable hemocytometer remains the inexpensive tool of choice. It is used with another common tool of the laboratory, a bright field optical microscope such that cells can be visualized and counted on a grid of squares.

In this application note, we will demonstrate how the hemocytometer cell counting process can be automated using a Cell Imaging Multi-Mode Reader equipped with contrast enhancement technologies. For total cell counts, the Cell Imager uses automated phase contrast microscopy to count the total number of cells in the field of view which is about 2.9 times larger than the total ruled grid area. This serves to improve the counting statistics relative to counting manually. Furthermore, cell viability can also be determined through the use of automated color imaging of tryptan blue stained cells in the same field of view.