Merck, B2261-25MG, bisBenzimide H 33342 trihydrochloride

General description
Fluorescent properties of bisBenzimide H 33342:
Free dye: Excitation maximum = 340 nm, Emission maximum = 510 nm (5 mM HEPES, 10 mM NaCl, pH 7.0) DNA complex: Excitation maximum = 355 nm, Emission maximum = 465 nm (5 mM HEPES, 10 mM NaCl, pH 7.0)
Application
Bisbenzimide Hoechst 33342 is a specific stain for AT-rich regions of double-stranded DNA and has been shown to displace several known DNA intercalators. This fluorescent dye has been used in sorting living cells based on DNA content, used in flow cytometry for the determination of DNA content, and for the visualization of chromatin distribution in living cells. It has been used to detect BrdU incorporation into cells and in studying the initial stages apoptosis and cellcycle distribution., Chromosomes that are dividing or replicating will not stain with this dye.
Useful for staining DNA, chromosomes and nuclei. May be used for fluorescence microscopy or flow cytometry.
Excitation max. = 346 nm
Emission max. = 460 nm
Biochem/physiol Actions
Membrane-permeable, fluorescent DNA stains with low cytotoxicity that intercalate in A-T regions of DNA.
Preparation Note
This product is soluble in water (50 mg/ml), yielding a clear solution. The pH of a 2% solution is 1.9. It has been observed that this material will precipitate from phosphate buffer solutions.
Aqueous solutions are stable for 1 month if kept in the dark at 2-8 °C.