Amperometric and Impedimetric Determination of Hydrazine at a Novel Trimethine Cyanine Dye Film Modified Glassy Carbon Electrode

In this study, we report the amperometric and impedimetric determination of hydrazine at a novel trimethine cyanine dye, 1H-Benz[e]indolium, 2–[3–(3–butyl–1, 3–dihydro–1, 1–dimethyl–2H-benz[e]indol–2–ylidene)–1–propenyl]–1, 1, 3–trimethyl–, hexafluorophosphate (DVD-R dye A4) or (DVDR) film modified glassy carbon electrode (GCE). The DVDR film was electrochemically deposited on a GCE surface by performing 20 consecutive cyclic voltammograms at the scan rate of 100 mV s-1 in the potential range between-0.8 and 2.0 V in 0.1 mM DVDR in 0.1 M H2SO4 solution. The SEM and AFM results revealed that DVDR film surface possess both flake and bead like structures. Cyclic voltammetry (CV) results demonstrated that DVDR film was electrochemically active and it showed a pair of well-defined redox peaks at a formal potential (E°′) of 5.5 mV in pH 7. Electrochemical impedance spectroscopy (EIS) results showed that rapid electron transfer process occurs at the DVDR/GCE surface than the bare/GCE surface. The electron transfer resistance (Ret) values obtained at the DVDR film increased linearly with increase in hydrazine concentrations between 0.05 mM–1.07 mM, which confirmed the excellent impedimetric hydrazine quantification. The DVDR film showed rapid amperometric i-t response towards hydrazine in the linear concentratio