– HOE 32020 is a Hoechst stain, a blue fluorescent dyes, used to stain DNA. Hoechst dyes are soluble in water and in organic solvents such as dimethyl formamide or dimethyl sulfoxide. Concentrations can be achieved of up to 10 mg/mL. Aqueous solutions are stable at 2-6°C for at least six months when protected from light. For long-term storage the solutions are instead frozen at ≤-20°C.