100ml Iodine (Lugol) Solution

Lugol's solution is an aqueous iodine and potassium iodide solution, supplied as 100 ml of laboratory grade liquid. The potassium iodide holds the elemental iodine in solution, giving a stable dark brown reagent.

It is used in the laboratory as a stain for starch and glycogen, as the mordant step in Gram staining, and in microscopy of plant and algal tissue. It also serves as an iodine source for titrations and other analytical work, and as a topical antiseptic. The solution stains skin, fabric and bench surfaces readily.