Automated cell counters do not all operate in the same way. From flow cytometer to image-based counters, various types of counter are available. This blog briefly introduces the different types of automated cell counter, mostly focusing on brightfield and fluorescence cell counters.
Types of automated cell counter
Automated cell counters are known to provide higher accuracy and consistency than manual counters. These automated counters, however, are not identical. Below are the three types of automated cell counting technique we commonly use today - image-based, flow cytometry and coulter (conductive) techniques.
Image-based cell counter
Image-based cell counter is the most commonly used counter with optical microscopy which takes images and analyzes cells. Cell images are captured using CCD or CMOS image sensor in a digital camera of a microscope and this microscope is divided into two types – brightfield and fluorescence. Choosing the right type for your cell sample is very important for accurate and precise results.[1]
Brightfield
Brightfield microscopy, also known as a light microscope, is the very basic optical microscopy technique. This brightfield technique illuminates sample and allows light to transmit through or reflect to provide an image for us to see. The image of samples will be shown in grayish color in contrast to white background. To use this technique, trypan blue (TB) stain is used to dye samples. One of the advantages of brightfield is it does not alter the color of your sample.[2]
Fluorescence
Fluorescence microscopy is a technique to detect samples labeled with a fluorescent marker or fluorophores using propidium iodide (PI) or acridine orange (AO) dyes. These dyes or fluorophores absorb excitation light of a certain wavelength and emit at a longer wavelength. The emitted light from the sample then passes through the emission filter and reaches the detector. As fluorescence microscopy provides better resolution and accuracy, it is often preferred over brightfield.
References:
1. Wu, Shu Yu, et al. “Investigation of Autofocus Algorithms for Brightfield Microscopy of Unstained Cells.” NASA ADS, vol. 9131, 1 May 2014, p. 91310T, ui.adsabs.harvard.edu/abs/2014SPIE.9131E..0TW/abstract, 10.1117/12.2051944. Accessed 25 Feb. 2022.
2. Chazot CAC, Nagelberg S, Rowlands CJ, Scherer MRJ, Coropceanu I, Broderick K, Kim Y, Bawendi MG, So P, Kolle M. Luminescent Surfaces with Tailored Angular Emission for Compact Dark-Field Imaging Devices. Nat Photonics. 2020 May;14(5):310-315. doi: 10.1038/s41566-020-0593-1. Epub 2020 Feb 24. PMID: 33584848; PMCID: PMC7877670.
Thought about getting your own automated cell counter? We'll help you choose the right one.
An automated cell counter
Analysis time | < 20 seconds/test |
Dye | Trypan blue |
Cell type | Cell line (clumped cell, single cell) |
Measuring range | 1x10E4 to 1x10E7 cell/mL |
The world's fastest automated cell counter
Analysis time | < 1 seconds (manual focus); <10 seconds (auto focus) |
Dye | Trypan blue |
Cell type | Cell line (clumped cell, single cell) |
Measuring range | 1x10E4 to 2x10E7 cell/mL |
A high-throughput automated cell counter
Analysis time | 3 minutes / 48 tests |
Dye | Trypan blue |
Cell size range | Detectable: 1 - 85 μm Optimal: 5 - 80 μm |
Measuring range | Detectable: 1x10E4 to 2x10E7 cells/mL Optimal: 1x10E5 to 1x10E7 cells/mL |
