Nickel oxide-modified composite electrode for electrochemical detection of polyhydroxyl compounds in liquid chromatographic analysis

摘要

Nickel oxide-modified polymeric composite electrode was prepared for electrochemical detection in liquid chromatography (LC-ECD) or flow injection analysis of polyhydroxyl compounds. The composite electrode was prepared by incorporating semigraphitic carbon black and nickel oxide particles in polystyrene polymer matrix cross-linked with divinylbenzene. The analytical characteristics of the elctrodes in LC-ECD and flow injection anlaysis of polyhydroxyl compounds were evaluated in terms of sensitivity, reproducibility, stability and surface renewability. The electrode revealed three-four orders of dynamic concentration ranges from sub-micromolar to 10~(-3) M with high correlation coefficients from 0.9998 to 0.999 for various poly-hydroxyl compounds. The standard deviation for the surface restoration was <2%. High reproducibility, stability, and the renewability of surface are thought to be due to the catalyst particles highly dispersed through robust polymeric electrode matrix.