Method of preparing D-gluconic acid(U-14C) of high molar activity

The invention claims enzyme action of glucose oxidase on a reaction mixture obtained by acid hydrolysis of polysaccharide(U-14C) soluble in water and separated from radioactive biological material, such as green algae in processing radioactive biomass. The advantages of the method include ease, high yield (around 67%), the possibility of preparing products of an activity higher than 100 mCi/mmol, and the possibility of repeating separation from the reaction mixture of glucose which has not reacted. (J.P.)