Redox probes are sometimes considered to be equivalent and to react with all free radicals equally, so choosing one may seem tricky. However, they tend to be more reactive towards one than others and so the suitability should be considered depending on the aim of the experiments and the samples to be tested. In this blog post, we are going to show the differences, similarities, reactiveness and recommendations for each probe from our catalogue, hoping to shed some light into this topic:

DHE, DCFH-DA and DHR-123


DHE – KP06002

Reacts directly with:

  • O2
  • H2Oin the presence of Fe2+ or cytocrome c


  • 2-OH-E+


Suitable for detection of intracellular oxidants However, red fluorescence measurements using fluorescence or confocal microscopy will not be able to distinguish between E+ and 2-OH-E+.

Measurement of H2O2 in the presence of Fe2+ or cytochrome c; and O2



Reacts directly with:

  • OH
  • Compounds I and II
  • NO2 formed from the myeloperoxidase/ H2O2/NO2 system
  • Hypoclorus acid (HOCl)
  • Reactive species formed form peroxynitrite (ONOO/ONOOH) decomposition
  • H2Oin the presence of Fe2+

Reacts indirectly with:

  • H2O2


  • Heme proteins: hemoglobin, cytochrome c released during apoptosis
  • O2 : Artifactual amplification of the fluorescence signal intensity


Suitable as a redox indicator probe for uncovering new redox signaling mechanisms keeping in mind the various caveats.

Measurement of H2O2, ROO· and ONOO