Simple Spectrophotometric Method for Analysis of Serum Catalase Activity
Dr. Mahmoud Hussein Hadwan,
Al-Imam Ali St. Hilla, Hilla City, Babil, Iraq.
Introduction: Catalase is a principal constituent of the antioxidant system that attenuates the oxidative stress, which is ubiquitously associated with several types of pathological disorders.
Aim: This paper describes a discontinuous assay for the assessment of catalase activity using the titanium tetrachloride/sulfuric acid reagent.
Materials and Methods: Samples containing catalase are incubated with hydrogen peroxide for three minutes prior to fast mixing of aliquots of the incubation mixtures with titanium tetrachloride/sulfuric acid reagent, which measures remaining hydrogen peroxide (H2O2). Absorbance is then read at 405 nm. Dissociation of hydrogen peroxide is proportional to catalase activity in the used sample. One-way analysis of variance (ANOVA) was used to analyse the resulted data. p-value <0.05 was considered to be statistically significant using SPSS Statistics 17.0 software.
Results: The current method characterizes the use of a correction factor to exclude the interference that arises from the presence of a yellow background colour of serum and/or reducing agents that reduce titanium (IV) to titanium (III). The imprecision of the method was considered by calculating the coefficient of variation, which equals to 3.6% within run and 5.7% between run. The catalase assay measured using the kinetic method produced a good correlation (r=0.9771).
Conclusion: The study explains a simple discontinuous method for catalase activity assessment which can be completed with few steps, and which allows catalase to be measured in the presence of high concentration of other molecules as well as at low levels of H2O2.