Enzymatically Catalyzed Generation of Electronically Excited States in a Synthetic Copolymer with a Schiff Base in Pendant Groups
The copolymer of N -(2-hydroxypropyl)methacrylamide and N -[ N -( N -methacryloylglycyl)glycyl]hexane- 1,6-diamine (17.6 mole %) was prepared as a model compound for investigation of the mechanism of enzymatically catalyzed generation of electronically excited states in proteins. The amino end groups of the copolymer side chains were transformed into a Schiff base by reaction with glycolaldehyde. The modified copolymer was characterized by its ultraviolet, visible and fluorescence spectra. The enzymatically catalyzed oxidation of the modified copolymer was carried out in a phosphate buffer at pH 7 using horseradish peroxidase as the enzyme. The generation of electronically excited states was demonstrated by chemiluminescence measurement and by a spectroscopic procedure based on transfer of the excitation energy to bilirubin.