Radiation stability of angiotensin II-amide and of its tritiated derivatives

The gamma-radiolysis of aqueous solutions of the peptide hormone angiotensin II-amide and the beta-autoradiolysis of its tritiated preparations were studied. The radiation loss and the decrease of biological activity of angiotensin II-amide was evaluated. The main fractions of radiation products were separated and compared with the products formed during the storage of tritiated angiotensin II-amide. The principal radiation processes taking place during the irradiation of angiotensin II-amide were discussed.