The writer describes an accurate and reliable method for preparing an iodine stain for use in wet preparations containing intestinal protozoa.
To a 1 per cent standardized potassium iodide solution is added 1.5 grams of powdered iodine crystals per 100 cc., in order to provide an amount of iodine considerably in excess of saturation and to compensate for volatilization. The solution is allowed to stand for 4 days and is then filtered.
To insure success in the preparation of the stain, several points must be observed:
The advantages of this new standardized iodine stain over those prepared by the older methods now in use may be summed up as follows: