Protect from light. Luminol is a very versatile chemical that exhibits chemuluminescence with a striking blue glow when reacted with an appropriate oxidizing agent. Luminol is soluble in most polar organic solvents but is insoluble in water. Luminol is used by forensic investigators to detect amounts of blood left at crime scenes, as it reacts with iron found in hemoglobin. It is used in cellular assays for the detection of copper, iron and cyanides, as well as of specific proteins by Western blot assay. In a laboratory setting, the catalyst used is often potassium ferricyanide. When Luminol reacts with the hydroxide ion, a dianion is formed. The oxygen produced from the hydrogen peroxide then reacts with the Luminol dianion. DNA can be successfully extracted from samples treated with Luminol reagent.