4',6-Diamidino-2-phenylindole dihydrochloride 

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.

Protect from light.

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.

≥98% (HPLC and TLC)

powder

λ_ex 340 nm; λ_em 488 nm (nur DAPI)

λ_ex 364 nm; λ_em 454 nm (DAPI-DNA-Komplex)

H₂O: 10 mg/mL Heat or sonication may be required. Solutions stored in the dark at room temperature or 4 °C should be stable for 2 to 3 weeks.

PBS: insoluble

ε/263 nm, H₂O 30

cell culture tested

2-8°C

Naimski, P., Quantitative fluorescent analysis of different conformational forms of DNA bound to the dye, 4', 6-diamidine-2-phenylindole, and separated by gel electrophoresis. Anal. Biochem. 106, 471, (1980)

Zaitsev, E.N., Kowalczykowski, S.C., Binding of double-stranded DNA by Escherichia coli RecA protein monitored by a fluorescent dye displacement assay. Nucleic Acids Res. 26, 650-654, (1998)

Uphoff, C.C., et al., Sensitivity and specificity of five different mycoplasma detection assays. Leukemia 6, 335-341, (1992)

Hotz, M.A., et al., Flow cytometric detection of apoptosis: comparison of the assays of in situ DNA degradation and chromatin changes. Cytometry 15, 237-244, (1994)

Collins, J.A., Major DNA fragmentation is a late event in apoptosis. J. Histochem. Cytochem. 45, 923, (1997)

Jeppesen, C.,, Nielsen, P.E, Photofootprinting of drug-binding sites on DNA using diazo- and azido-9-aminoacridine derivatives. Eur. J. Biochem. 182, 437, (1989)

Otto, F.J., High-resolution analysis of nuclear DNA employing the fluorochrome DAPI. Methods Cell Biol. 41, 211-217, (1994)

Kapuscinski, J., DAPI: a DNA-specific fluorescent probe. Biotech. Histochem. 70, 220-233, (1995)

Darzynkiewicz, Z. and Li, X., Cotter, T.G. and Martin, S.J., ed., Measurements of cell death by flow cytometry, in Techniques in Apoptosis: A User's Guide. Cytometry London, U.K. , (1996), 91-92

Uphoff, C.C., et al., Mycoplasma contamination in human leukemia cell lines. I. Comparison of various detection methods. J. Immunol. Methods 149, 43-53, (1992)

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