Catalog # Availability Size / Price Qty
DAPI | CAS No. 28718-90-3 | Fluorescent DNA Stains
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Description: Fluorescent DNA dye; DAPI can be used for cell staining and assessing apoptosis; suitable for flow cytometry; DAPI mw and DAPI ex/em, provided
Alternative Names: DAPI Dye

Chemical Name: 2-[4-(Aminoiminomethyl)phenyl]-1H-Indole-6-carboximidamide hydrochloride

Purity: ≥95%

Product Details

Biological Activity

DAPI is a fluorescent DNA stain / dye. DAPI stain binds to AT-rich regions of DNA and fluorescence increases by approximately 20-fold when bound to double-stranded DNA. DAPI stain can be used in flow cytometry, DNA visualization and quantification in histochemistry/biochemistry, to assess apoptosis, and to visualize mouse embryos or fetal organs. DAPI stain can be used in fixed cells and is cell-permeable at high concentrations providing effective cell staining. It is reported to be more photostable than Hoechst 33342 (Cat. No. 5117). Em/Ex λ = 350/470 nm respectively.

Use of DAPI Stain as Nuclear Counterstain in HeLa Cells

DAPI stain as nuclear counterstain on HeLa cells

3-plex RNAScope™ Multiplex Fluorescent v2 Assay on HeLa cells with TSA Vivid dyes 520, 570 and 650. Nuclei are counter-stained with DAPI stain (blue). All dyes were used at 1:1500 dilution. Markers shown are Polr2a (green), PPIB (red) and UBC (white).

Optical Data for DAPI

DAPI Dye Spectra
Emission Color Blue
λabs 350 nm
λem 470 nm
Application Flow cytometry, ISH

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Use our spectra viewer to interactively plan your experiments, assessing multiplexing options. View the excitation and emission spectra for our fluorescent dye range and other commonly used dyes.

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Technical Data

Soluble to 100 mM in DMSO and to 10 mM in water with gentle warming
Store at -20°C

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.
Tocris products are intended for laboratory research use only, unless stated otherwise.

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