Studies are given to illustrate surface adsorption of144Ce,90Sr,232Th,235U,239Pu, and241Am on diethylene-glycol-succinate, DGS. Adsorption of these elements was studied from aqueous and phosphate solutions. Adsorption was found to depend on pH, age of the tracer solution, hydrolysis states of the radioelement and the ionic strength of the solution. The adsorption phenomenon which was particularly well observed could be used as a separation stage in a method for the determination of gross activity in urine. Recoveries of about 85% were obtained.