A gasometric method to determine erythrocyte catalase activity

Abstract

We describe a new gasometric method to determine erythrocyte catalase activity by the measurement of the volume of oxygen produced as a result of hydrogen peroxide decomposition in a system where enzyme and substrate are separated in a special reaction test tube connected to a manometer and the reagents are mixed with a motor-driven stirrer. The position of the reagents in the test tube permits the continuous measurement of oxygen evolution from the time of mixing, without the need to stop the reaction by the addition of acid after each incubation time. The enzyme activity is reported as K Hb , i.e., mg hydrogen peroxide decomposed per second per gram of hemoglobin (s -1 g Hb -1 ). The value obtained for catalase activity in 28 samples of hemolyzed human blood was 94.4 ± 6.17 mg H 2 O 2 s -1 g Hb -1 . The results obtained were precise and consistent, indicating that this rapid, simple and inexpensive method could be useful for research and routine work. Correspondence

New colorimetric method to determine catalase mimic activity

“…Furthermore, the excessive levels of hydrogen peroxide (H 2 O 2 ) lead to the realization of small bubbles in the solution which cause an error in the measurements [6]. CAT activity can be measured by other approaches such as the titration method, which is the sample does not allow in the spectrophotometer method when the precipitation or pigmentation was formed [1,7]. Goth [8] used other colorimetric methods for CAT by measuring spectrophotometrically the unreacted H 2 O 2 by reacting a compound with the ammonium molybdate.…”

Synthesis and Catalase Mimic Activity of MnO2 Nano Powder Prepared by Hydrothermal Process

“…Moreover, the high levels of H2O2 lead to formation of bubbles in the test cell which cause mistake measurements [8]. Catalase (catalytic) activity can be determined in other methods such as by titrimetric determination of H2O2 concentration, determination of oxygen production from decomposition of H2O2 by oxygen electrode [9,10]. There are simple colorimetric methods such as by Goth [11] for catalase, by measuring of hydrogen peroxide (unreacted) spectrophotometrically by a complex reaction with ammonium molybdate.…”