This article also applies to meCUT&RUN and Multiomic CUT&RUN.
Important Notes
Trypan Blue is toxic to cells. After adding Trypan Blue dye to cells, move quickly to determine cell viability.
Materials needed
Reagent |
|---|
Trypan Blue solution, 0.4% (e.g. Invitrogen T10282) |
Hemocytometer with brightfield/phase microscope or automated cell counter (e.g.) Countess automated cell counter) |
Protocol
Add 10 µL of 0.4% Trypan Blue to 10 µL washed cells/nuclei. Pipette to mix.
Transfer 10 µL of cell-Trypan Blue mix to a counting slide.
View under brightfield/phase microscope or cell counter.
Assess cell/nuclei morphology and viability and troubleshoot as needed.
Viable cells are impermeable to Trypan Blue and will exclude the dye (Trypan Blue negative; Figure 1A).
Dead cells are permeable to Trypan Blue and will stain Trypan Blue positive (Figure 1A).
Isolated nuclei will stain Trypan Blue positive (Figure 1B).
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Figure 1. (A) Washed K562 cells are mostly viable (bright white and round). A dead cell (blue, Trypan positive) is circled in red. (B) Successful nuclei harvest shows Trypan Blue stained nuclei. An intact cell (bright white, Trypan negative) is circled in red.