Propidium Iodide

Propidium Iodide - FAQs

View additional product information for Propidium Iodide - FAQs (P1304MP)

3 product FAQs found

I want to use propidium iodide and SYTO 9 to do LIVE/DEAD testing of a bacterial sample. Will anaerobic conditions adversely affect the assay?

Oxygen content should not affect the binding of propidium iodide and SYTO 9 to nucleic acids. SYTO 9 will label all cells, and propidium iodide will label only dead cells or cells with a compromised membrane.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

I have a LIVE/DEAD BacLight Bacterial Viability kit that has SYTO 9 and propidium iodide in it. Will I be able to stain eukaryotic cells that have engulfed bacteria and determine if the bacteria are alive or dead using this kit?

Unfortunately, no. SYTO 9 will label the nuclei of live or dead cells, including the eukaryotic cells. Propidium iodide is cell impermeant, and will only enter dead cells. If the eukaryotic cells are dead, they will label with propidium iodide as well. If the eukaryotic cells are alive, propidium iodide will not be able to enter and thus will not label the bacteria inside, whether the bacteria are alive or dead. We are not aware of any way to do a viability assay of bacteria once they have been engulfed by cells.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.

Is propidium iodide (PI) fixable with glutaraldehyde or paraformaldehyde (PFA)?

PI is not fixable with glutaraldehyde or PFA. Both reagents fix by crosslinking amines. PI and other nucleic acid stains do not inherently bind covalently to nucleic acids and these fixatives do not crosslink the dyes to nucleic acids.
The one fixable nucleic acid stain is Ethidium Monoazide Bromide (EMA), Cat no. E1374); it covalently binds to nucleic acids upon activation by exposure to light.

Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.