ENHANCER EFFECT OF FLUORESCEIN ON THE LUMINOL-H2O2-HORSERADISH PEROXIDASE CHEMILUMINESCENCE - ENERGY-TRANSFER PROCESS

The chemiluminescence of the luminol-H2O2-horseradish peroxidase syste m is increased by fluorescein. Fluorescein produces an enhancement of the luminol chemiluminescence similar to that of phenolphthalein, by a n energy transfer process from luminol to fluorescein. The maximum int esity and the total chemiluminescence emission (between 380 and 580 nm ) of luminol with fluorescein was more than three times greater than w ithout fluorescein; however, the emission duration was shorter. The em ission spectra in the presence of fluorescein had two maxima (425 and 535 nm) and the enhancement was dependent on pH and fluorescein concen tration. A mechanism is proposed to explain these effects. (C) 1997 Jo hn Wiley & Sons, Ltd.