ELECTROGENERATED CHEMILUMINESCENCE .57. EMISSION FROM SODIUM 9,10-DIPHENYLANTHRACENE-2-SULFONATE,THIANTHRENECARBOXYLIC ACIDS, AND CHLORPROMAZINE IN AQUEOUS-MEDIA

The anodic oxidation of aqueous sodium 9,10-diphenylanthracene-2-sulfonate (DPAS) and 1- and 2-thianthrene-carboxylic acid (1- and 2-THCOOH) in the presence of tri-n-propylamine as a coreactant in aqueous solution produces electrogenerated chemiluminescence (ECL), In addition, the cathodic reduction of DPAS in the presence of peroxydisulfate as a coreactant also produces ECL in an acetonitrile-water solution (1:1 v/v), For DPAS, both the oxidative and the reductive ECL spectra are characteristic of DPAS fluorescence, with peak intensities at 430 nm, In contrast, the ECL spectra for 1- and 2-THCOOH are significantly red-shifted from the fluorescence spectra, indicating that the emission arises from a product of THCOOH rather than the excited state of the intact acid, The oxidation of chlorpromazine produces an ECL emission in the absence of an added coreactant following an unprecedented ''self-annihilation'' mechanism. These new aqueous ECL reactions should be useful in the design of new labels for ECL analysis of biomolecules (i.e., immunoassays, DNA probes).