1H-n.m.r. investigation of radiolysis products of some irradiated aminoacids and aliphatic peptides

Glycide (gly), glycyl-glycine (gly-gly), α-alanine (α-ala) and glycyl-α-alanine (gly-α-ala), either in dry form or in aqueous solutions, were irradiated by 60Co gamma rays at a dose rate of 1 Mrad/h (100 rads=1 Gy). The main radiolysis products have been identified and characterized using H-n.m.r. techniques. In the case of gly-gly, the major radiolysis product was N-acetyl-glycine (N-ac-glyc) identified by its protons at 2.03 ppm and 3.73 ppm (methyl group and methylene group, respectively). The relative intensity of methyl group protons at 2.3 ppm was found to be proportional to the absorbed dose. Therefore it is suggested that this system can be used as a dosimeter for high dose rate measurements of ionizing radiation. 12 refs., 4 figs., 1 tab. (author)