DISSOLVED-OXYGEN DETERMINATION BY ELECTROCATALYSED CHEMILUMINESCENCE WITH IN-LINE SOLID-PHASE MEDIA

Dissolved elemental oxygen is determined in a flowing aqueous stream u sing glucose oxidase to catalyse the reaction between D-glucose and O- 2 to produce hydrogen peroxide. The revels of the resulting H2O2 are d etected and quantified by luminol chemiluminescence using in-line soli d phase media for pH adjustment of the reagent stream and for controll ed release of the luminophore. The reaction is initiated by electroche mical catalysis. By the use of excess D-glucose in the reagent flow st ream, the intensity of chemiluminescence is rendered proportional only to fluctuations in the dissolved O-2 concentration. The methodology p rovides a means for the detection of aqueous O-2 in the range 0-10 mg/ L. (C) 1998 John Wiley & Sons, Ltd.