College of Veterinary Medicine

Flow Cytometry Laboratory

Use of Propidium Iodide for Labeling Dead Cells for Flow Cytometry


  1. Label cells with primary and secondary antibodies using the standard procedure and FITC conjugates.
  2. After the final wash, resuspend the cells in 200 ml of a 1:1000 dilution of PI stock. Stock PI is 0.5 mg/ml in PBS. Dilute 10 ml stock in 10 ml PBS before using. Analyze on flow cytometer immediately.
  3. The dead cells will be labeled with PI and will show up in FL3.
Last Edited: Feb 17, 2010 5:57 PM   

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