Last Updated on
September 27, 2023
When Robert Hooke first discovered the cell in the 17th century, researchers were just becoming aware of the microscopic units that built up all life. Since that discovery, scientists have taken great pains to refine how we see the human body through a microscopic lens. Such efforts have culminated in a deep appreciation for the cell’s role in keeping our bodies healthy and our world together.
With investigations into cell biology come additional efforts to count cells. For centuries, researchers have known that disturbances in blood strongly indicate that a person is sick. After cells were first discovered, subsequent research allowed researchers to count all kinds of cells in the blood. Inventions such as the hemocytometer made manual cell counting possible, but further technological advances have since automated this process. With such advances, cell counting has become that much easier and more accurate.
At Excedr, we will help you push your cell counting efforts forward by giving you a primer on the subject and showcasing the cell counters we can lease.
Cell counting represents any method researchers use to count the number of cells in a sample. Researchers can count cells through several approaches, both manually and automated (insert link to automated liquid handlers here). Scientists also classify cell counting under cytometry, the ability to measure cells by their size and characteristics.
In most cases, scientists measure cell viability, which determines the number of viable cells and dead cells in cell culture. However, researchers can also measure many other traits in cells, including cell size, cell type, activity level, DNA content, and the proteins they produce inside and at the membrane.
Measuring these traits allows researchers to distinguish different kinds of cells as they conduct total cell counts. Irrespective of the approach, having an accurate cell count represents the primary goal of cell counting techniques.
Having an accurate count of viable cells is essential for many experimental pipelines. In fact, many protocols require researchers to accurately count the number of cells for downstream experiments:
Irrespective of the experimental workflow, cell counting always involves three steps: sampling and processing, cell counting, and calculations.
Distinguishing cells by their characteristics depends on having a way to differentiate them when counting cells. Staining a cell sample represents one such approach. Cell staining relies on dyes that interact with cellular components to color them. Scientists have developed several dyes to characterize cells, most of which distinguish a cell membrane’s integrity:
Irrespective of the dye employed, preparing samples for cell counting is a sequential process. From the total volume of the sample, cell lines must first be pelleted with a centrifuge. Then, the cell pellet must be isolated and washed. After obtaining a purified cell fraction, staining can occur. Scientists then use a pipette to transfer the sample volume into a cell counter for counting.
Amid that process, scientists must consider several factors to ensure the success of cell counting efforts:
Hemocytometers (also spelled hemacytometers) are inexpensive tools used to manually count cells with light microscopy. All hemocytometers look like microscopy slides, but they have large squares and smaller squares that make manual cell counting easier.
For its ability to The cell counting apparatus also contains a slit where samples are introduced in microliter volumes. Then once the samples are added, researchers place a coverslip on top to prevent samples from evaporating.
Hemacytometers were first developed to count red blood cells. Since then, researchers also count unicellular organisms and other cells dispersed from multicellular organisms with a hemocytometer. Over the next century, scientists developed multiple kinds of hemocytometers with varying counting grid arrangements.
The different layouts produce varying counting areas that allow researchers to count different types of cells at varying abundances.
Hemocytometers are an affordable tool for counting cells within a sample. However, the variation in sample counts increases with more dilute samples, leaving a lower limit of detection of 25000 cells/mL of sample. This stems from the 10000-fold dilutions that take place when pipetting the sample volumes into the hemacytometer.
Counting multiple sample aliquots can increase accuracy. Nonetheless, obtaining multiple aliquots can be challenging should little samples be available. That’s why researchers have also turned to cell counters for their cell counting efforts.
Cell counters are the hardware that detects characteristics inherent in specific cell types. The first automated cell counters harnessed the Coulter Principle to count cells. Under the Coulter Principle, cells are insulators that reduce electric current within a saline solution.
The first cell counter had an aperture where an electric current was passed through. There, the cells would pass through the aperture and cause transient reductions in electric current. Since then, newer cell counters have automated identifying cells through algorithms.
Excedr boasts several automated cell counters from diverse vendors that streamline your cell counting efforts. Each of these counters boasts unique features that will help you with any of your experimental needs:
Cell counting is one of the earliest techniques researchers use to diagnose a person’s health through blood. In recent years, researchers have also expanded its uses to count other kinds of cells, both human and microbial.
While hemacytometers have historically enabled manual cell counting efforts, an automated cell counting process will allow more experiments to be done quickly and reproducibly. With many experiments requiring accurate cell counts as controls, companies are following suit with their lines of cell counters.
If you want reproducible counts for your experiments, speak with us today. We can provide you with cost-effective hemacytometer and automated cell counter leases for high-throughput cell counting. Because we don’t carry an inventory, you can decide which system works best for your research needs. Take advantage of our brand-agnostic leasing program and push your cell counting efforts forward today!
Are you interested in leasing a hemacytometer or a cell counter? Let us know!