Thermo Fisher counter Countess3/3FL - fully automatic cell counting

Thermo Fisher counter Countess3/3FL - fully automatic cell counting

In the fields of cell culture, drug screening, and cell therapy research and development, the accurate evaluation of cell concentration and activity is directly related to the reliability and reproducibility of downstream experimental data. The traditional manual counting of blood cells on a hemocytometer is not only significantly affected by subjective differences among operators, but also falls short when dealing with complex samples containing clustered cells or large amounts of cell debris. Thermo Fisher counter Countess3 and Countess3FL as Invitrogen ™ The new generation of automatic cell counting systems under its umbrella are equipped with high-precision AI image analysis algorithms based on deep learning neural networks, which can automatically complete the entire process of focusing, lighting, counting, and saving in a short period of time. The core parameters of the two are consistent in terms of processing time, sample size, concentration range, etc. The difference is that Countess3 is the basic model of bright field (only trypan blue staining), while Countess3FL adds dual channel fluorescence detection capability on the basis of bright field. Through the replaceable EVOSLED light cube, the application scope is expanded from conventional cell passaging to more in-depth research scenarios such as transfection efficiency evaluation, cell apoptosis detection, and fluorescent protein expression analysis.

Choosing the Thermo Fisher counter Countess3 means equipping your daily cell quality control with a precise and efficient bright field automation solution; Choosing the Thermo Fisher counter Countess3FL means gaining fluorescence analysis capabilities beyond bright field counting, providing multidimensional data support for more complex research needs.

1、 The core positioning difference between the two models: layered selection of bright field and fluorescence

In the Countess3 series product line, the positioning of the two Thermo Fisher counter Countess3/3FL is clear and complementary to each other. Countess3, as a basic model, only performs cell counting and activity detection in bright field (trypan blue staining) mode, replacing traditional manual blood cell counting plates with automated processes, suitable for daily applications such as routine cell passaging, vitality determination, and concentration estimation. Countess3FL retains all the functions of the basic model while adding a dual channel fluorescence detection system, which can count in bright field or fluorescence dual mode. It achieves fluorescence detection capability through two replaceable EVOSLED light cubes, greatly expanding the application range of the device.

Both Countess3/3FL counters from Thermo Fisher have the common characteristics of accuracy, speed, simplicity, and automation. They support cell viability measurement and single-cell data generation, are compatible with reusable counting boards to reduce long-term usage costs, and can be optionally equipped with software modules that comply with 21CFR Part 11 electronic recording compliance requirements.

2、 Comparison of core technical parameters (two identical)

The two Thermo Fisher counter Countess3/3FL are based on the same optical core and algorithm platform, maintaining high consistency in the following key parameters, so users do not need to readjust to the operation process when switching models.

Comparison dimension Countess3 (bright field type) Countess3FL (fluorescence type)

Detection mode: Brightfield+dual fluorescence channel only

Fluorescent cube does not support 2 slots, 14 spectral ranges can be selected

Detection time<30 seconds (bright field about 20 seconds) bright field about 20 seconds/fluorescence about 30 seconds

The sample concentration range is 1 × 10 ⁴ -1 × 10 𔑃 cells/mL, which is the same

The cell diameter range is approximately 4-60 μ m, which is the same

The sample volume is 10 μ L (the detection area is only 0.4 μ L), which is the same

Optical system with a 5-megapixel camera and the same 2.5x optical magnification

The instrument size is 228.6 × 139.7 × 228.6mm, which is the same

Weighing approximately 3.6kg, the same

Touch screen 1280 × 800 high-resolution capacitive screen is the same

Compliance supports optional software that complies with 21CFR Part 11

Application scenarios include conventional cell passaging, vitality detection, concentration determination, transfection efficiency, apoptosis analysis, fluorescent protein expression, etc

The two are consistent in terms of optical performance, automatic focusing, automatic light intensity adjustment and other automation functions, ensuring seamless integration of user experience between different models.

AI Deep Learning Neural Network Algorithm: The Intelligent Core for Accurately Dealing with Complex Samples

Both Countess3/3FL counters from Thermo Fisher are equipped with deep learning neural network algorithms based on artificial intelligence. The system is trained and optimized by professional scientists based on hundreds of culture plates containing dozens of different cell types, and can automatically identify and eliminate cell debris interference. Even for difficult samples containing clustered cells or debris, it can accurately distinguish between live and dead cells.

Unlike traditional algorithms that rely on fixed thresholds, the AI model of the Thermo Fisher counter Countess3/3FL continuously iterates and optimizes through the accumulation of new data. The automatic adjustment of brightness and autofocus functions significantly reduce operational differences between users, and batch CV values can be controlled at a lower level. The repeatability is significantly better than that of manual blood cell counting plates.

Mingchang Counting: An Efficient Experience of Two Step Cell Activity Evaluation

In bright field mode, the operation process of the two Thermo Fisher counter Countess3/3FL is minimalist. Users only need to mix 10 μ L of cell samples with 10 μ L of 0.4% trypan blue staining solution, transfer the solution to a Countess disposable or reusable counting plate, and the instrument will automatically complete the entire process within about 20 seconds after insertion. It will directly display multiple data such as live and dead cell counts, cell viability, average cell size, and cell aggregation percentage. For daily passage operations that require rapid assessment of cell status, this efficiency improvement significantly reduces the time and labor costs required for manual counting.

The measurement range of the two Thermo Fisher counter Countess3/3FL covers 1 × 10 ⁴ to 1 × 10 ⁷ cells/mL, which is much wider than the measurement range of manual hemocytometers, reducing the need for pre dilution and dilution errors of high concentration samples. The built-in pre dilution calculator and cell passage calculator can be seamlessly integrated into the counting process, further simplifying the experimental preparation steps.

Fluorescence detection: deep functional extension of Countess3FL

The fluorescence ability of the Thermo Fisher counter Countess3FL is its core upgrade compared to the base model. The instrument is equipped with two EVOSLED light cube slots, allowing users to choose two installations from 14 light cubes with different spectral ranges, expanding the application range from GFP and RFP to multispectral fluorescence applications such as DAPI and Cy5.

In the key application of rapid evaluation of transfection efficiency, the Thermo Fisher counter Countess3FL can simultaneously obtain fluorescence signals (such as the proportion of GFP positive cells) while counting in the bright field, visually presenting transfection or transduction efficiency. This is particularly important for cutting-edge research such as CAR-T cell screening and CRISPR gene editing efficiency validation.

In apoptosis analysis, the Countess3FL counter can be paired with fluorescent reagents such as AnnexinV, JC-1, Caspase3/7 to simultaneously identify apoptotic cells as well as live and dead cells, providing multidimensional cell state information for drug screening and toxicity studies.

In terms of optimizing cell nuclear counting, the fluorescence mode of the Countess3FL from the Thermo Fisher counter is significantly more accurate than the bright field in separating cell nuclei, as there are often many cell fragments associated with extracting cell nuclei from tissue samples. The measured data shows that in the counting test of cell nuclei separated from multiple tissue sources, the CV value range can be controlled between -4.8% and 6%, demonstrating good repeatability.

In addition, the Countess3FL from Thermo Fisher counter supports InvitrogenReadyCountGreen/Red reactive dyes (including optimized AO/PI mixtures), which can provide higher sensitivity for distinguishing live/dead cells without changing cell morphology. Compared with the trypan blue method, it has better performance in small cell counting such as PBMC.

Consumables System and Data Management

The two Thermo Fisher counter Countess3/3FL are compatible with both disposable chamber slides and reusable counting plates. Disposable glass slides do not require cleaning, effectively avoiding cross contamination; Reusable counting boards are more environmentally friendly and economical, suitable for laboratories that use them frequently. The data export method of the Thermo Fisher Countess3/3FL counter is flexible and diverse. Users can directly export data to their computer through a USB drive, or wirelessly transfer it to the ThermoFisher Connect cloud platform using a WiFi adapter (sold separately), achieving remote data management and team collaboration.

For laboratories that comply with GLP/GMP standards, the Countess3/3FL counter from Thermo Fisher can be optionally equipped with the CountessSAE software module, which meets 21CFR Part 11 electronic record compliance requirements, including audit trail and electronic signature functions. The data report format covers multiple options such as PNG, JPG, TIFF, PDF, CSV, FSC, etc., adapting to different data processing and archiving needs.

3、 Selection Decision Framework and Price Reference

When choosing the Thermo Fisher counter Countess3/3FL, users can make precise judgments between the bright field model and the fluorescence model based on experimental needs and budget.

Conventional cell culture and passage: Countess3 bright field model can meet the needs of daily cell viability detection and concentration determination. In the 2025 procurement project of Shenzhen University, the winning bid price for 4 Countess3 units is 59600 yuan per unit.

Transfection efficiency evaluation and fluorescence application: For fluorescence application scenarios such as CAR-T cell screening, CRISPR editing efficiency validation, cell apoptosis detection, and fluorescent protein expression analysis, Countess3FL model should be selected.

Cell nucleus counting and complex samples: Countess3FL has an advantage in extracting cell nucleus counts from tissue samples or processing complex samples containing more fragments due to its higher sensitivity in fluorescence detection.

Compliance requirements: The application must meet 21CFR Part 11 electronic record compliance, and both models can be equipped with SAE software modules.

Consumables pairing: For frequent use, it is recommended to choose a reusable counting board to reduce long-term costs; Use disposable glass slides to avoid cross contamination scenarios.

summary

The Countess3 of Thermo Fisher counter meets the daily needs of cell passaging and vitality detection with bright field counting. The Countess3FL of Thermo Fisher counter expands the deep application of transfection efficiency evaluation, apoptosis detection, and complex sample analysis with dual fluorescence channels. Both share the same core parameters, AI deep learning algorithms, and 21CFR Part 11 compliance support, allowing the laboratory to flexibly upgrade according to actual needs without changing operational processes and consumables configurations. Choosing the appropriate model based on your experimental type, sample complexity, and budget conditions will help improve the efficiency and data reliability of cell analysis work.

Thermo Fisher counter Countess3/3FL - fully automatic cell countingThe instruments in Hangzhou Qiannuo Biological Warehouse can be ordered online.