Abstract
The commercially available rose bengal was fractionated into different compounds using Sephadex G-25 column on gelfiltration. Physical properties of each fraction were determined. A fraction that was considered to be composed of the same substances as radiochemical impurities observed by paperchromato graphic analysis of131I-rose bengal was labeled by radioactive iodine. The effect of these labeled compounds on rose bengal liver uptake test and the distribution of the compounds in rat were investigated. The liver uptake levels of the labeled different compounds reached to the maximum at fifteen minutes after i.v. administration. The maximum liver uptake levels of these compounds were proved to be approximately one-half of the radiochemically pure labeled rose bengal liver uptake. It will be indicated that decrease of radiochemical purity of131I-rose bengal might cause the decrease of the liver uptake of131I-rose bengal.
A careful attention should be payed on the purification of the raw material at the manufacturing process of131I-rose bengal, and also confirmation of radiochemical purity should be made when it is used.
