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Propidium Iodide - CAS 25535-16-4 - Calbiochem

Membrane impermeable DNA intercalator.

Propidium Iodide - CAS 25535-16-4 - Calbiochem
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
MDL number:

Quality Level





storage condition

OK to freeze
protect from light


dark red


sample type intact cells


λex ~536 nm
λem ~617 nm

shipped in


storage temp.




InChI key


Related Categories

General description

Extinction coefficient(493 nm): 5900 M -1cm-1;(287 nm): 55,700 M -1cm-1;
Membrane impermeable DNA intercalator. Has red fluorescence at 488 nm. Useful for flow cytometry for staining apoptotic cells and nuclei. Can be used to differentiate between apoptotic and necrotic cell death while stains only necrotic cells. Can be used together with common green fluorescent probes labeled with fluorescein isothiocyanate (FITC).
Membrane impermeable DNA intercalator. Has red fluorescence at 488 nm. Useful for staining apoptotic cells and nuclei by flow cytometry. Can be used to differentiate between apoptotic and necrotic cell death. Can be used together with common green fluorescent probes labeled with fluorescein isothiocyanate. Has the following spectral properties: extinction coefficient: 5,900 M-1cm-1 (493 nm); 55,700 M-1cm-1 (287 nm); 13,800 M-1cm-1 (252.5 nm); excitation maximum: 536 nm; emission maximum: 617 nm.


1 g in Plastic ampoule
250 mg in Plastic ampoule
50, 100 mg in Glass bottle

Biochem/physiol Actions

Primary Target
Membrane impermeable DNA intercalator
Product does not compete with ATP.
Reversible: no
Cell permeable: no


Toxicity: Irritant (B)

Preparation Note

Solubility may be improved by first dissolving in a very small amount of DMSO, then adding material to an aqueous solution.


Following reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C.

Other Notes

Belloc, F., et al. 1994. Cytometry 17, 59.
Crompton, T., et al. 1992. Biochem. Biophys. Res. Commun. 183, 532.
Darzynkiewicz, Z., et al. 1992. Cytometry13, 795.
de Caestecker, M.P., et al. 1992. J. Immunol. Methods154, 11.
Pollice, A.A., et al. 1992. Cytometry13, 432.

Legal Information

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany


Health hazard

Signal Word


Hazard Statements

Hazard Classifications

Muta. 2

Storage Class Code

11 - Combustible Solids



Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Certificate of Analysis

Certificate of Origin

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