Voltammetry of resazurin at a mercury electrode

Cakir S., Arslan E. Y.

CHEMICAL PAPERS, cilt.64, sa.3, ss.386-394, 2010 (SCI İndekslerine Giren Dergi) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 64 Konu: 3
  • Basım Tarihi: 2010
  • Doi Numarası: 10.2478/s11696-010-0007-9
  • Sayfa Sayıları: ss.386-394


Electrochemical behavior of resazurin on HMDE in Britton-Robinson (B-R) buffers (pH 2.0-10.0) was studied using the square-wave voltammetry (SWV), square-wave adsorptive stripping voltammetry (SWAdSV), and cyclic voltammetry (CV) techniques. The voltammogram of resazurin in B-R buffer at pH < 4.0 exhibited two cathodic reduction peaks. The voltammetric peaks were obtained at -0.144 V (reversible) and -1.250 V (irreversible) at pH 3.2, and correspond to the reduction of resorufin to dihydroresorufin and to the catalytic hydrogen wave, respectively. At pH > 4.0, a new irreversible cathodic reduction peak, assigned to the protonation of N-oxide on the phenoxazin ring, was observed. Electrochemical parameters (I (p)/E (p), I (p)/v, I (p)/pH, I (p)/t (acc)) of the compound were determined. From the voltammetric data, electrochemical reduction mechanisms for all peaks have been suggested. Maximum peak current for the reversible peak was obtained at pH 4.1. A linear relationship between the current and concentration was determined, and also the lowest detection limit was found as 3.25 x 10(-8) mol L-1 and 1.98 x 10(-10) mol L-1 for SWV and SWAdSV, respectively.