SONOCHEMISTRY OF AQUEOUS SOLUTIONS OF AMINO ACIDS AND PEPTIDES. A SPIN TRAPPING STUDY.

The sonolysis of argon-saturated neutral aqueous solutions of several amino acids and peptides was investigated by ESR and spin trapping. The water-soluble non-volatile spin trap, 3,5-dibromonitrosobenzene sulfonate, was found to be particularly useful for ESR and spin trapping investigations of sonochemical reactions. By comparison with analogous experiments in which hydroxyl radicals were generated by u. v. -photolysis of solutions containing hydrogen peroxide, the amino acid and peptide radicals produced by sonolysis could be identified. These observations can be explained by the reactions of hydrogen atoms and hydroxyl radicals which are the primary products of the sonolysis of water.