How to determine the concentration of hydrogen peroxide , by...

Both the intensity and distribution of the stain can be used to determine the extent of DAB staining which is consequently proportional to hydrogen peroxide accumulation levels. Both of these can be worked out using a variety of bioimaging softwares available such as ImageJ or CellProfiler. A bit of effort is required to set up these methods and the best advice I can give is reading the tutorials on these software to learn their capability, then playing around with high resolution photographs of your DAB stains. However, DAB is not a specifically quantitative stain in the protocol that I have described, and I do not know of a way to quantify the actual, accurate concentration of H2O2 with our methods. For that, you can use other methods such as xylenol orange or luminol detection.