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DAPI (4',6-diamidino-2-phenylindole) is a fluorescent stain that binds strongly to A-T rich regions in DNA. It is used extensively in fluorescence microscopy.
D 3851 (OTTO) 4',6-Diamidino-2-phenylindole dihydrochloride (DAPI) Cas 28718-90-3 - used to stain DNA and chromosomes for fluorescent microscopy and flow cytometry applications.