Sodium dodecyl sulfate sensitized electrochemical method for subnanomole level determination of ortho-phenylphenol at a novel disposable electrode

The electrochemical behavior of ortho-phenylphenol (OPP) at a disposable electrode (an improved wax-impregnated graphite electrode) in the presence of sodium dodecyl sulfate (SDS) was studied for the first time. The results demonstrated that the electrocatalytic oxidation process of OPP was accompanied with two-charge-two-proton transference. The electronic transmission coefficient (α) and diffusion coefficient (DR) for OPP were calculated to be 0.8126 and 3.61 × 10−2 cm2/s, respectively. The electrochemical signal was apparently improved by SDS at the disposable electrode and the oxidative peaks current was proportional to the concentration of OPP over the range from 1.0 × 10−9 to 4.0 × 10−6 mol/L with the detection limit of 8.7 × 10−10 mol/L. This novel and highly sensitive method can be successfully applied to detect OPP in the orange rind sample.