Electrochemical behavior of 2,6-dicholorophenol-indophenol in aqueous solutions

2,6-Dichlorophenolindophenol is part of the Hill reagents family, which has been widely used as a redox dye in determination of the rate of photosynthesis [1], vitamin C [2] and NADH [3]. It has also, acid-base indicator properties. Its color is red in acidic media and blue in alkaline media [4]. So, it is used as indicator in various acid-base titrations. The absorption spectra of the acidic and basic forms of the indicator are presented. Therefore detailed mechanistic information is important in the understanding of the stability and identifying the intermediates structure resulting from the oxidation/reduction of this compound. In this work we study the electrochemical behavior of 2,6-dicholorophenol-indophenol using cyclic voltammetry technique at the surface of glassy carbon at various scan rate and pH in aqueous solutions. Accoring to voltammetric data, we propose the following Scheme for the electrochemical oxidation/reduction of 2,6-dicholorophenol-indophenol in aqeous solutions.