Factors affecting the preparation of 99mTc-sulfur colloid

Some factors, such as the effect of mannitol as 'stabilizer', increased concentration of thiosulfate, autoclaving conditions, etc., that can affect the preparation of 99mTc-sulfur colloid and consequently its biodistribution into different tissues are discussed. Also discussed are parameters, such as distribution with respect to time, effect of storage, preloading dose, etc., that can influence the uptake of the radiopharmaceutical by the RES in animals and humans.