The Electrochemical Redox Behaviour of Acid Blue 25 and its Quantitative Measurement at Carbon Paste Electrode: A Voltammetric Study

The electrochemical oxidation and reduction behavior of acid blue 25 (ab 25) at carbon paste electrode (cpe) was investigated by employing cyclic voltammetry (cv) and differential pulse voltammetry (dpv) techniques. ab 25 was an anthraquinonic and anionic dye and it gives two reversible redox systems at potential values ?0.2 v and ?0.56 v respectively. the effect of ph on the anionic dye was studied and it was conformed that the ph-7.0 of phosphate buffer solution (pbs) was the suitable supporting electrolyte for further studies. we have studied the effect of accumulation time, scan rate, concentration, and repeatability. we have proposed a mechanism for the redox behavior of ab 25. it was conformed that one system at 0.2 v was diffusion controlled, where as the other system at 0.56 v was controlled by adsorption process. we have determined the limit of detection (lod) and limit of quantification (loq) values as 3.248×10-8 m and 10.22×10-8 m respectively. by using electrochemical impedance spectroscopic (eis) study we have observed the surface nature of the different electrodes