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Immunofluorescence (Immunocytochemistry)

Immunofluorescent analysis of HeLa cells using COX IV (3E11) Rabbit mAb #4850 (green), β-Catenin (L54E2) Mouse mAb (IF Preferred) #2677 (red) and DAPI (blue).

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Immunofluorescence (Immunocytochemistry)

Immunofluorescent analysis of HUVE cells using VE-Cadherin (D87F2) XP® Rabbit mAb #2500 (green) and DAPI (blue). Actin filaments were labeled with DY-554 phalloidin (red).

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Product Description

DAPI is supplied as a lyophilized powder in 1 mg units. It can be used to examine cellular DNA in fluorescent microscopy applications.

Molecular Formula:

C16H15N5 2(HCl)

Fluorescent Properties

  • Free dye excitation maximum = 340 nm
  • Free dye emission maximum = 488 nm
  • DNA complex excitation maximum = 364 nm
  • DNA complex emission maximum = 454 nm

Product Usage Information

This product is soluble up to 20 mg/ml in deionized water or dimethylformamide yielding a clear yellow solution. Heating and/or sonication may be required. For standard fluorescence based assays, DAPI stock solutions should be diluted in phosphate-buffered saline or mounting medium to a final working concentration of 1 to 0.1 μg/mL.

Storage: Store desiccated and protected from light at 2-8°C. Lyophilized DAPI is stable for 2 years under these conditions. Soluble DAPI is stable for at least 2-3 weeks if protected from light.

4', 6-diamidino-2-phenylindole, dihydrochloride (DAPI) is a blue fluorescent DNA dye that targets double-stranded AT clusters in the DNA minor groove (1). One molecule of dye binds to each 3 base pairs of dsDNA and yields an approximate 20-fold fluorescent enhancement (2). The level of DAPI-DNA fluorescence is proportional to DNA content (3).

1.  Portugal, J. and Waring, M.J. (1988) Biochim Biophys Acta 949, 158-68.

2.  Kapuscinski, J. (1995) Biotech Histochem 70, 220-33.

3.  Manzini, G. et al. (1983) Nucleic Acids Res 11, 8861-76.

For Research Use Only. Not For Use In Diagnostic Procedures.
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