Electrogenerated chemiluminescence of ZnO nanorods and its sensitive detection of cytochrome C.

Various kinds of ZnO nanoparticles have been successfully used in gas sensing applications, however, these nanomaterials have been rarely investigated in electrogenerated chemiluminescence (ECL). In the present work, ZnO nanorods (ZnONRs) were synthesized by hydrothermal method, and characterized by field emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD). ECL behaviors of ZnONRs were investigated in neutral aqueous condition in the presence of K2S2O8. Cyclic voltammetry (CV) results revealed that ZnONRs can react with K2S2O8 to generate strong light emission, revealing that K2S2O8 can act as coreactant of ZnONRs ECL. ZnONRs synthesized under different pH conditions exhibited different ECL intensities, and the most intense ECL signal was obtained at pH 7.0. Cytochrome C could compete with ZnONRs to react with K2S2O8, and exhibited apparent inhibiting effect on ZnONRs ECL, which can be sensitively detected in the range of 1.0 × 10-11-5.0 × 10-9molL-1, with a detection limit of 4.7 × 10-12molL-1 (3σ). The present ECL system exhibited high sensitivity and good stability, which is suitable for the fabrication of novel ECL sensors.