CHEMICAL INDICATORS AS ENHANCERS OF THE CHEMILUMINESCENT LUMINOL H2O2HORSERADISH-PEROXIDASE REACTION

The chemiluminescent emission from the luminol-H2O2-horseradish peroxi dase system was enhanced between 2 and 80 times, during the first 5 mi n, by chemical indicators, such as phenolphthalein, cresolphthalein, p henol red, cresol red, benzidine and o-tolidine. Phenol derivatives sh owed emission maxima at pH 8.5, while aniline derivatives showed emiss ion maxima at pH 10.5. The enhancers with a methyl group at the ortho or para position to the OH and NH2 groups in the benzene ring showed a n inhibitory effect when their concentrations were increased.