Abstract:

A novel water-soluble poly(p-phenylenevinylene) derivative was electropolymerized at glass carbon electrode by cyclic voltammetric method or two-potential steps method to develop a sensitive nitric oxide(NO) sensor.  The experimental results show  that the sensor exhibits apparent current response to NO by cyclic voltammetry.  Two anodic peaks potential  significantly shifted negatively copared with bare GCE.  The oxidation current(measured by chronoamperometry) is linear with NO concentration ranging from 1.8×10^-7 to 1.0×10^-4 mol/L with a linear coefficient of 0.999 3.  The detection limit of NO is 2.3×10^-8 mol/L(S/N=3).  The electrochemical behavior of NO on this sensor was also characterized by rotating disk electrode.  The results also indicate that the oxidation of NO proceeds in two steps.  Rotating disk experiments yield a diffusion coefficient of NO in 0.1 mol/L PBS at 20 ℃, that is DNO=2.92×10^-5 cm²/s.  The value of DNO was validated by chronocoulometry.

Key words: Poly(p-phenylenevinylene) derivative; Sensor; Rotating disk electrode; Nitric oxide; Diffusion coefficient