Image of NucRed® Live 647 ReadyProbes® Reagent

Nuclear stain for live cells

NucRed Live 647 ReadyProbes Reagent is a bright far-red cell-permeant nuclear stain for live or fixed cells. 

This protocol can be used for:

  • Nuclear staining to identify nuclear condensation in apoptotic cells using fluorescence microscopy

This protocol should not be used for:

  • Flow cytometry

You will need the following for this protocol:


1. Culture cells in an appropriate medium and vessel for fluorescence microscopy.
2. Add two drops of NucRed Live 647 Reagent per milliliter of medium.
3. Incubate for 15–30 minutes. 
4. Image the cells.
Spectral information and storage
Excitation/Emission (nm)642/661
Standard filter setCy®5
EVOS Light CubeCy®5
Storage conditionsRoom temperature


Protocol tips

  • In some cases, more or fewer drops may be needed to achieve optimal staining intensity.
  • Image quality may be improved by replacing the culture medium with Live Cell Imaging solution.

Nuclear staining in live hUVECs
Nuclear staining in live hUVECs. hUVECs were grown overnight, stained with NucRed Live 647 ReadyProbes Reagent for 20 minutes at 37°C, and then imaged.