The determination of actinium-227 in urine

Abstract

A method is described for the determination of actinium-227 in urine. After oxidation of the urine sample with nitric acid, actinium is co-precipitated on barium sulphate. The barium sulphate is converted into carbonate, dissolved in acid and the actinium co-precipitated on iron(III) hydroxide to remove barium and radium. The iron(III) hydroxide precipitate is dissolved in a mixture of nitric and hydrochloric acids and the solution passed through an anion-exchange column upon which iron, thorium and protactinium are absorbed. The column effluent, which contains the actinium, is essentially free from solids. Sources for α-counting may be prepared either by evaporation or by electro-deposition. Actinium recoveries of about 80 per cent. are obtained, with good decontamination from protactinium, thorium, radium, polonium and lead.