Close Btn

Select Your Regional site


Electrolytic ESR - Generation of p-Benzoquinone anion radical -


Overview of Electrolytic ESR Cell

ESR has been applied to inorganic and organic compounds in an attempt to capture the reaction product of the oxidation or reduction of a single electron by an electrochemical reaction in solution. In this study, the helix electrode electrolytic cell (ES-EL30) was used for the electrolytic ESR. In this cell, the gold wire is coiled to increase the effective area of the working electrode and to suppress microwave absorption by the dielectric liquids. Since this electrolytic cell has high electrolytic efficiency, it can produce anion and cation radicals easily. This cell can be used with a variable temperature controller.

Generation of p-Benzoquinone anion radical

The sample was prepared by mixing the following reagents.

  • Sample :p-Benzoquinone (C6H4O2) 1 mM
  • Supporting Electrolyte:Tetrapropylammonium Bromide  100 mM
  • Solvent :Dimethylformamide


Figure1. p-Benzoquinone structure.

ESR signal was observed by applying a constant voltage between two electrodes in the electrolytic cell. ESR spectrum of five lines with a splitting constant of 0.24 mT and a signal intensity ratio of 1:4:6:4:1 was observed by applying a voltage of 1.0 V for about 17 minutes. This spectrum shows the generation of p-Benzoquinone anion radical (BQ-・) due to its hyperfine structure by the four equivalent protons on the benzene ring[1].

Figure 2. ESR spectrum of p-Benzoquinone anion radical (Voltage:1.0V)

Figure 2. ESR spectrum of p-Benzoquinone anion radical (Voltage:1.0V).


[1] H.Park et al (2002): In-Situ ESR Detection of Radical Species of p-Benzoquinone in Aqueous Media, Electroanalysis,14, No21, 1501-1507.

Please see the PDF file for the additional information.
Another window opens when you click.




Are you a medical professional or personnel engaged in medical care?



Please be reminded that these pages are not intended to provide the general public with information about the products.

Science Basics

Easy explanation about mechanisms and
applications of JEOL products


JEOL provides a variety of support services to ensure that our customers can use our products with peace of mind.
Please feel free to contact us.