Propidium Iodide Ready Flow™ Reagent (Invitrogen™)

Propidium Iodide Ready Flow™ Reagent is a bright, easy-to-use nucleic acid stain for distinguishing dead cells from live cells in flow cytometry assays. This dye has excitation/emission maxima of 535/617 nm.

• Stable at room temperature
• Convenient, ready-to-use format—no need to dilute, weigh. or pipette
• Rapid staining of dead cells without wash steps

Propidium Iodide Ready Flow Reagent is a commonly used dead-cell stain that emits red fluorescence when bound to DNA. Add 2 drops from the dropper bottle directly into 1 x 10⁶ cells, incubate, and analyze.

Propidium iodide is membrane impermeant and therefore excluded from viable cells. It binds to DNA by intercalating between the bases, thereby binding both DNA and RNA. Propidium iodide is commonly excited with the 488 nm laser, but others such as the 532 and 561 nm lasers are also suited for PI excitation.