ON THE PRODUCTS OF RADIATION-CHEMICAL TRANSFORMATIONS OF HUMAN SERUM-ALBUMIN IN AQUEOUS-SOLUTIONS

Polymeric products are formed upon radiolysis of human serum albumin ( HSA) in air- or N2O-saturated berate buffer (pH 7.4), as shown by gel chromatography and electrophoresis. Products with fluorescence at lamb da(max)(f) = 410-420 nm and lambda(max)(ex) = 335-337 nm were detected in irradiated HSA solutions. The scavenger technique (tert-butanol, s odium formate, and KBr were used as scavengers) demonstrated that thes e products are formed by an attack of OH radicals on the tryptophan an d tyrosine residues.