MDCK cells, Phase Contrast, red outlines are marking the cell borders. Courtesy of Prof. Ralf Jacob, University of Marburg, Germany
MDCK cells, Phase Contrast, red outlines are marking the cell borders. Courtesy of Prof. Ralf Jacob, University of Marburg, Germany

Confluency Check with PAULA Cell Imager

Monitor your cell culture around the clock with PAULA and know the perfect time-point for your experiment

Many cell-based experiments require cells in a certain state. This can include their morphology, fluorescent protein expression, and the confluency of the cell layer. Researchers check their cells regularly to determine these attributes. Confluency estimation can be very difficult! This guess work is biased by every individual researcher, and can result in lab error.

MDCK cells, Phase Contrast, red outlines are marking the cell borders. Courtesy of Prof. Ralf Jacob, University of Marburg, Germany


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How to determine cell confluency

PAULA – the Personal AUtomated Lab Assistant from Leica Microsystems – helps you to automate confluency checks and find the perfect time-point for your experiment. With the help of the Confluence app, PAULA precisely measures the confluency of your cell culture. PAULA can even be operated at 37°C, 5% CO2, and in humidity so that you can observe your cells in their natural state. Thus, PAULA helps you to do your cell culture experiments always at the right time point.


  • Adjustment free phase contrast
  • Red/green fluorescence
  • Operation inside cell incubator (37°C, CO2, ~90% humidity)
  • Automated cell confluency measurement
  • Monitor your cells from anywhere, at any time

Confluency Check Workflow

Typical fields of research: Cell culture, Cell monitoring, Confluence check, Stem cell research, Organoids, Spheroids, Wound healing

Step 1: Cell Seeding

Seed your cells on your preferred cell culture container. Just do your routine work and place the cells at the stage of PAULA – inside your incubator! Set your desired illumination method and focus the cells.

Step 2: Cell Growth

Let the cells settle down and start growing. Cell confluency, morphology, and growth can be hard to determine when you're busy! PAULA constantly observes your cells so you don't have to. 

Cell Growth

Step 3: Cell Confluency - Check

Check your cells remotely with PAULA and your mobile device via the Confluence App. You can determine the confluency of your cells – live. In addition, the system will also track, document, and analyze growth. PAULA can email you when a specific confluency has been reached. You'll never have to worry about checking your cells again. 

Step 4: Transfection

After you are notified of the desired confluency status of your cells, they can be transfected.  Just do your routine transfection assay and give your cells back to PAULA inside the incubator.

Step 5: Cell Check – Transfection Result

Continue watching your cells remotely. Check your transfection with the help of Phase Contrast and Red/Green fluorescence. 

You can document your results easily with a single touch. All data will be saved and can be exported later on. 

Step 6: Analysis

Now the cells are ready for your experiment. Analyze the cells with your preferred analytical approach:

  • Fluorescence microscopy
  • Confocal microscopy
  • TIRF microscopy
  • Super-Resolution microscopy
  • Biochemistry
  • Molecular biology 

PAULA Cell Imager

Your Personal Automated Lab Assistant for Cell Monitoring

Cell culture monitoring has never been easier. PAULA measures your cell culture confluency automatically and reproducibly. PAULA enables you to watch your cells around the clock remotely if you wish, without even being in the cell culture lab.

With PAULA in your lab, you will always find the right time for your downstream experiments.

Further information

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