Rapid radioiodination of rose bengal at room temperature

Published methods for radioiodination of rose bengal require reaction times of 1 hr or more at temperature from 50 to 120 degrees C. Through the use of an acidified ethanol solvent and potassium iodate oxidant, purified rose bengal is radioiodinated at room temperature within 15 min with chemical yields ranging between 93 and 97%. Radiochemical impurities are sufficiently minimized to permit preparation in a single 10-ml serum vial, requiring no additional purification steps. The method reported here is readily adaptable to cold-kit preparation.