A technique for monitoring hydrogen peroxide concentration off-line and on-line

A simple technique using a low flow gas meter is described for the off-line and on-line measurement of hydrogen peroxide. The volume of oxygen produced from the reaction of the enzyme catalase with hydrogen peroxide was followed. A linear correlation was demonstrated between total O 2 evolution and H 2O 2 concentration in the range 0.25–1.5% for on-line assays and 25–500 mg/l and 0.38–3% for the off-line method. A response time of 17 min was obtained for the off-line for hydrogen peroxide concentrations of 25–500 mg/l. The response time of an on-line version of the method was approximately 5 min for hydrogen peroxide concentrations of 0.25–1.5%. The technique was not significantly temperature sensitive in the range 25–45°C.