(R8) Lugol's 1% iodine solution for direct examination of fresh or formalin-ether/ethyl acetate concentrated feces

Composition

-     Iodine crystals                                                          1 g

-     Potassium iodide (KI) crystals                                    2 g

-     Distilled water                                                     100 ml

Procedure

-     Dissolve the potassium iodide in 10-20 ml distilled water;

-     Slowly add iodine crystals to get a homogeneous solution;

-     Add the remaining water, stir well and filter.

This solution is quite stable and keeps its staining properties for about one month if stored in a tightly sealed brown glass bottle sheltered from sunlight. A ready to use 1% iodine solution stabilized with PVP (polyvinyl-pyrrolidone) is commercially available and has superior stability (1 year). For use, see: “Microscopic examination with stains for temporary (wet mount) preparations”.