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  • 32670 - 4′,6-Diamidino-2-phenylindole dihydrochloride

32670 Sigma

4′,6-Diamidino-2-phenylindole dihydrochloride

BioReagent, suitable for fluorescence, ≥95.0% (HPLC)

Synonym: 2-(4-Amidinophenyl)-6-indolecarbamidine dihydrochloride, DAPI dihydrochloride

  • CAS Number 28718-90-3

  • Empirical Formula (Hill Notation) C16H15N5 · 2HCl

  • Molecular Weight 350.25

  •  Beilstein Registry Number 4894417

  •  EC Number 249-186-7

  •  MDL number MFCD00012681

  •  PubChem Substance ID 57648699



Related Categories Biochemicals and Reagents, Detection, Fluorescent Enzyme Substrates, Fluorescent Enzyme Substrates for Electrophoresis, Fluorescent Probes, Labels, Particles and Stains,
product line   BioReagent
assay   ≥95.0% (HPLC)
solubility   DMF: soluble
  H2O: soluble
fluorescence   λex 340 nm; λem 488 nm (nur DAPI)
  λex 364 nm; λem 454 nm (DAPI-DNA-Komplex)
  λex 374 nm; λem 461 nm in 10 mM Tris; 1 mM EDTA; pH 8.0; DNA
suitability   suitable for fluorescence


Frequently Asked Questions

Frequently Asked Questions are available for this Product.

Biochem/physiol Actions

Cell permeable fluorescent minor groove-binding probe for DNA. Binds to the minor groove of double-stranded DNA (preferentially to AT rich DNA), forming a stable complex which fluoresces approximately 20 times greater than DAPI alone.


Bottomless glass bottle. Contents are inside inserted fused cone.


DAPI is several times more sensitive than ethidium bromide for staining DNA in agarose gels. It may be used for photofootprinting of DNA, to detect annealed probes in blotting applications by specifically visualizing the double-stranded complex, and to study the changes in DNA and analyze DNA content during apoptosis using flow cytometry. DAPI staining has also been shown to be a sensitive and specific detection method for mycoplasma.

Price and Availability

Safety & Documentation

Safety Information

NONH for all modes of transport
WGK Germany 
Protocols & Articles


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Keywords: Amplification, Applications, Biochemistry, Clinical, Glycosylations, Methods, Microscopy, Protocols, Tools

Nancy-520 for DNA Detection and Quantitation

Nancy-520 is a fluorescent stain for double stranded DNA (dsDNA) on agarose electrophoresis gels, with higher sensitivity than ethidium bromide and an easy, fast, and robust staining procedure. It is...
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BioFiles 2009, 4.1, 4.
Keywords: Catalytic combustion detector, Electrophoresis

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