Delayed luminescence of luminol initiated by a membrane-bound peroxidase

The luminescense of the luminol-H2O2 system was initiated by either free or membrane-bound horseradish peroxideae (HRP). The instantaneous luminescene decayed rapidly and was followed by the delayed luminescence in the presence of excess luminol. The delayed luminescence was characterized by a chain reaction, in which luminescence intensity increased exponentially. Membrane-bound HRP demonstrated that the delayed luminescence took place even in the absence of HRP if the instantaneous luminescence was initiated by HRP. A mechanism for the nonenzymatic luminescence is proposed and discussed.