Hoechst 33258 is a blue fluorescent dyes used to stain DNA. A concentration of 0.1-12 µg/ml is commonly used to stain DNA in bacteria or eukaryote cells. Cells are stained for 1-30 min (dependent on section thickness) at room temperature or 37 °C and then washed to remove unbound dye. Dye is excited by ultraviolet light at around 350 nm, and emits blue-cyan fluorescent light around an emission spectrum maximum at 461 nm.
This dye is used as substitutes for another nucleic acid stain called DAPI Catalog # 09224.