Nonenzymatic Sensor for Hydrogen Peroxide using a Carbon Paste Electrode Modified with a Composite Consisting of Silver Nanoparticles, poly(o-aminobenzoic acid) and Magnetite

摘要

A nonenzymatic hydrogen peroxide (H2O2) sensor using a carbon paste electrode (CPE) modified witha composite consisting of silver nanoparticles (AgNPs), poly(o-aminobenzoic acid) (P(ABA)) andmagnetite (Fe3O4) is reported. The AgNPs-P(ABA)-Fe3O4 composite was prepared under sonicationand characterized using transmission electron microscopy (TEM), thermogravimetric analysis (TGA),and vibrating sample magnetometer (VSM). Electrochemical investigations indicated that a carbonpaste electrode modified with AgNPs-P(ABA)-Fe3O4 exhibits excellent performance in theelectrochemical reduction of H2O2 at an applied potential of -0.4 V versus Ag/AgCl (sat. 3.0 M KCl)in phosphate buffer solution. Under optimum condition, the calibration curve for H2O2 was obtained ina wide range of 5 M to 5.5 mM with the limit of detection (LOD) of 1.74 M (S/N = 3). The AgNPs- P(ABA)-Fe3O4 modified electrode has a good stability in practical conditions. In addition, thefabricated sensor was applied to determine H2O2 in real samples with good results.