New strategy for simultaneous and selective voltammetric determination of norepinephrine, acetaminophen and folic acid using ZrO2 nanoparticles-modified carbon paste electrode

A novel ZrO2 nanoparticles-modified carbon paste electrode (ZONMCPE) was fabricated and used to study the electrooxidation of norepinephrine (NE), acetaminophen (AC), folic acid (FA) and their mixtures by electrochemical methods. Using differential pulse voltammetry (DPV), a highly selective and simultaneous determination of NE, AC and FA has been explored at the modified electrode. Differential pulse voltammetry peak currents of NE, AC and FA increased linearly with their concentrations at the ranges of 1.0 × 10−7–2.0 × 10−3 M, 1.0 × 10−6–2.5 × 10−3 M and 2.0 × 10−5–2.5 × 10−3 M, respectively and the detection limits for NE, AC and FA were 8.95 × 10−8, 9.12 × 10−7and 9.86 × 10−6 M, respectively. The modified electrode displayed strong function for resolving the overlapping voltammetric responses of NE, AC and FA into three well-defined voltammetric peaks. In the mixture containing NE, AC and FA, the three compounds can well separate from each other with potential differences of 220, 290 and 510 mV between NE–AC, AC–FA and NE–FA, respectively, which was large enough to determine NE, AC and FA individually and simultaneously.