Countess II FL Automated Cell Counter
The only cell counter with the option for a reusable hemocytometer and fluorescence capabilities
With the option for a reusable slide and fluorescence capabilities—brightfield and two user-changeable fluorescence channels—the Invitrogen Countess II FL Automated Cell Counter can count cells, monitor fluorescent protein expression, and measure cell viability.
- Affordable—option for reusable slide to significantly reduce consumables cost
- Accuracy—eliminate the subjectivity of manual cell counting and minimize user-to-user variability
- Speed—count live and dead cells and measure viability and average cell size in as little as 10 seconds
Now affordable—option for reusable or disposable slides
The mounting costs of disposable slides and tips have deterred many labs from giving up tedious manual cell counting. In response to this, the Countess II FL instrument was designed to work with a reusable glass slide , which significantly reduces the long-term consumable costs of automated counting. For researchers who want the convenience of disposable slides, the Countess II FL instrument can also use the same PMMA plastic slides developed for the original Invitrogen Countess cell counter.
"It outperformed all other competitor's models that we tried."Michael DaCosta, The Jackson Laboratory
Advanced autofocusing and counting algorithms
The Countess automated cell counters contain advanced autofocusing and counting algorithms to allow you to quickly and accurately identify and count cells within a population (Figure 1). Countess instruments are compatible with a broad range of cell types and cell lines, and we have validated their use on a number of commonly used cell lines. Upon insertion of the slide the Countess instrument will automatically focus on cells, which helps to minimize user variation associated with manual focusing. Cells between ~7 µm and 60 µm and in suspension at a density of 1 x 104 to 1 x 107 cells/mL are optimal for counting.
- Download the application note: Comparison of cell counting using Countess II Automated Cell Counters vs. hemocytometers
Figure 1. User variability counting with a hemocytometer compared to using a Countess II instrument. Identical samples of A549, COS-7, HeLa, and U2OS cells were counted by three different operators using a Countess II Cell Counter and then manually with a hemocytomer and microscope. The user-to-user variability for the hemocytometer is much higher than for the Countess II instrument.
The additional time it takes to manually count cells using a hemocytometer (up to 5 minutes) compared to counting with the Countess II automated cell counters (10 seconds) is often overlooked as an added cost. An individual counting five slides per day (two samples per slide) can save ~10 hours per month by switching to an automated counter with a reusable slide. The time savings increases to ~15 hours per month when using disposable slides (Figure 2). This additional time can be applied to other activities in the lab, resulting in a significant advantage when switching from manual to automated cell counting.
Figure 2. Estimated hours saved per month when switching from counting cells with a hemocytometer to using an automated cell counter.
Accuracy comparable to flow cytometry
Flow cytometry and manual cell counting with a hemocytometer and microscope are the gold standards for fluorescent protein expression analysis, but both require advanced training for users and relatively expensive instrumentation. The Countess II FL Automated Cell Counter has two optional, user-interchangeable fluorescent channels. The colors collected are determined by the insertion of individual light cubes; more than 20 light cubes are available.
The Countess II FL Automated Cell Counter is able to count fluorescent cells with comparable accuracy, but with faster turnaround and greater cost-effectiveness while reducing user-to-user variability (Figure 3).
Figure 3. Comparison to flow cytometry with PBMCs. Invitrogen EVOS GFP and Texas Red dye light cubes were installed in the Countess II FL instrument. PBMCs were labeled with 5 and 3 μg/mL acridine orange and ethidium homodimer, to identify all cells and dead cells, respectively. The same sample was analyzed in parallel on an Invitrogen Attune NxT Flow Cytometer, where the Countess II FL results were confirmed.
Full spectrum of fluorescence detection—not limited to GFP and RFP
The Countess II FL instrument has two fluorescence channels. The fluorescent colors collected are determined by the insertion of individual light cubes. With 20 light cubes to choose from, the Countess II FL instrument is not limited to detection of GFP- and RFP-expressing cells. Looking to measure the transfection efficiency of cells transduced with an RFP-expression construct with a blue nuclear counterstain? No problem. Simply add the RFP and DAPI light cubes, and you can effectively count the number of cells expressing the RFP fusion within the total population and accurately determine the transfection efficiency.
A Texas Red light cube is available for optimal analysis of mCherry expressing cells, a very popular and commonly expressed fluorescent protein. To obtain viability information for these cells, simply utilize one of the Invitrogen LIVE/DEAD fixable dyes that are offered in a range of colors to meet the application need. This spectrum of flexibility is possible using the user-interchangeable EVOS light cubes with the Countess II FL (Figure 4).
- Read the application note: Fluorescent viability assays on the Countess II FL Automated Cell Counter
- Download the application note: Blood cell counting using the Countess II FL Automated Cell Counter
Figure 4. Detection of GFP- and Texas Red dye–expressing cells. Live and heat-killed cells were mixed, and then stained with calcein AM and ethidium homodimer supplied with the Invitrogen LIVE/DEAD Viability/Cytotoxicity Kit. The resultant solution was then evaluated using the GFP and Texas Red light cubes with the Countess II FL automated cell counter.
Up to two optional user-changeable light cubes
Central to the fluorescence detection technology inside the Countess II FL instrument are the proprietary Invitrogen EVOS LED light cubes. Each cube contains an LED, illuminating optics, and filters. Light cubes are user-changeable and auto-configured by the Countess system with plug-and-play capability . Our wide selection provides flexibility for multiple fluorescence research applications, such as cell viability analysis.
|Included in the box||
Researchers use Invitrogen Countess II and Countess II FL Cell Imaging Systems in their labs every day. Here's what some of our users have to say:
"Fast count and nice instruments, easy to use!! I love the small counter!"Dr. Xin Xu, Baylor College of Medicine
"It's very easy to use and it also allows me to quickly update my lab notebook so that each experiment uses the same number of cells. Quick and efficient."Lakeisha Tillery, Meharry Medical College
"It outperformed all other competitor's models that we tried."Michael DaCosta, The Jackson Laboratory
"It's very consistent!"Kim Sylvia, Sanford Burnham Medical Research Institute
"It is very effective at counting cells. It works very well."Mairead Bretney, Sanford Burnham Medical Research Institute
"The Countess II makes it very easy to count cells accurately and quickly - the fact that it tells you the dead cell and live cell count is icing on the cake."Faryal Mir, MIT
"We compared to a hemocytometer and the Countess II always obtained very close results. The fluorescent measurements are a great tool for us to quantify the % transfection and transduction efficiency in our experiments. The light cubes used to detect fluorescence are very easy to switch out when more than two fluorescence sources are needing to be detected. The automatic focusing is very effective and accurate with the option to manually focus."David Waynar, Santa Cruz Biotechnology
"This equipment is very useful for the purposes it is used in our lab. We love it!"Kristin Harwood, BioMarker Strategies, LLC
"Great for a quick check of transfection/transduction efficiency. Easy to use and seems pretty sensitive."Alex Peister, Morehouse College
"Great device. Broad range of cell densities that it can handle. Good at distinguishing clumps and counting cells within clumps."Joanna Rzepka, Veterinary Medical Research & Development
"Low maintenance, fast easy accurate cell counts. Easy for students to use and comprehend."Robert Dean, D'Youville College
"A very accurate cell counter and you can use it to count fluorescent cells as well. Excellent product. I'm very happy with it. I highly recommend it."Massimo Ammirante, University of California, San Diego
The result, image, and data files can be easily exported to a USB drive. The result and image files can be saved as .bmp, .jpg, .tiff, or .png files. The data file is saved as a .csv file that can be easily imported into your current analysis software or viewed in Excel™ software.
A comma-separated values (CSV) file stores tabular data (numbers and text) in plaintext form. Plain text means that the file is a sequence of characters, with no data that has to be interpreted as binary numbers. A CSV file can be opened with any third party software or spreadsheet program. The table below describes the categories of the Countess II data saved as a CSV file and opened with a spreadsheet program.
|General||A||Number||Sequential sample run number|
|B||File Name||Name of file|
|C||Date & Time||Date and time of sample run|
|D||Mode||BF-Brightfield or FL-Fluorescence|
|E||Total concentration||Concentration of the entire sample|
|F||Total cells counted||Total number of cells counted in the sample|
|G||Live concentration||Concentration of just the “live” portion of the sample|
|H||Live cells counted||Total number of “live” cells counted|
|I||Dead concentration||Concentration of just the “dead” portion of the sample|
|J||Dead cells counted||Total number of “dead” cells counted|
|K||Viability (%)||Percent viability of the sample based on trypan blue staining|
|L||Average size (μm)||Average cell size in microns|
|Fluorescence||M||Cube 1 name||EVOS light cube name in the first (top) position|
|N||Cube 1 concentration||Concentration of cells showing fluorescence in the first cube position|
|O||Cube 1 (%)||Percentage of the total cells in brightfield that show fluorescence in the first cube position|
|P||Cube 1 cells counted||Total number of cells counted in the first cube position|
|Q||Cube 2 name||EVOS light cube name in the second (bottom) position|
|R||Cube 2 concentration||Concentration of cells showing fluorescence in the second cube position|
|S||Cube 2 (%)||Percentage of the total cells in brightfield that show fluorescence in the second cube position|
|T||Cube 2 cells counted||Total number of cells counted in the second cube position|
|U||Cube 1+2 concentration||Concentration of cells showing fluorescence in the first and second cube positions combined|
|V||Cube 1+2 (%)||Percentage of the total cells in brightfield that show fluorescence in the first and second cube position combined|
|W||Cube 1+2 cells counted||Total number of cells counted in the first and second cube position combined|
|General Details||X||Focus value||Focal position number|
|Y||BF Light intensity||Brightfield light intensity value from 0-100%|
Brightfield Count Parameters
|Z||Live Size min||Minimum size of “live” cells in microns|
|AA||Live Size max||Maximum size of “live” cells in microns|
|AB||Live Brightness min||“Live” adjustment slider value for minimum brightness|
|AC||Live Brightness max||“Live” adjustment slider value for maximum brightness|
|AD||Live Circularity||“Live” adjustment slider value for circularity|
|AE||Dead Size min||Minimum size of “dead” cells in microns|
|AF||Dead Size max||Maximum size of “dead” cells in microns|
|AG||Dead Bright min||“Dead” adjustment slider value for minimum brightness|
|AH||Dead Bright max||“Dead” adjustment slider value for maximum brightness|
|AI||Dead Circ||“Dead” adjustment slider value for circularity|
|Fluorescence Count Parameters||AJ||Cube 1 Light intensity||First (top) light cube light intensity value from 0-100%|
|AK||Cube 2 Light intensity||Second (bottom) light cube light intensity value from 0-100%|
|AL||BF Size min||Minimum size of “Brightfield” cells in microns|
|AM||BF Size max||Maximum size of “Brightfield” cells in microns|
|AN||BF Brightness min||“Brightfield” adjustment slider value for minimum brightness|
|AO||BF Brightness max||“Brightfield” adjustment slider value for maximum brightness|
|AP||BF Circularity||“Brightfield” adjustment slider value for circularity|
|AQ||Cube 1 Brightness min||First (top) light cube adjustment slider value for minimum brightness|
|AR||Cube 1 Brightness max||First (top) light cube adjustment slider value for maximum brightness|
|AS||Cube 2 Brightness min||Second (bottom) light cube adjustment slider value for minimum brightness|
|AT||Cube 2 Brightness max||Second (bottom) light cube adjustment slider value for maximum brightness|
Counting has been successfully performed on the following cell lines using the Countess II FL Automated Cell Counter:
|Adipocytes||Human||Adipose-derived stem cells|
|Aortic smooth muscle||Human||Smooth muscle|
|Pulmonary artery endothelial||Human||Blood vessel|
|Pulmonary artery smooth muscle||Human||Smooth muscle|
|Umbilical vein endothelial||Human||Blood vessel|
|Whole lysed blood||Human||Blood|
NOTE: The reusable slide (Cat. No. A25750) is only compatible with the Countess II FL instrument.