Synergistic Effect of Zinc/aluminium-layered Double Hydroxide-clopyralid Carbon Nanotubes Paste Electrode in the Electrochemical Response of Dopamine, Acetaminophen, and Bisphenol A

A voltammetric sensor was developed using multiwalled carbon nanotubes (MWCNTs) paste electrode based zinc/aluminium-layered double hydroxide-clopyralid for simultaneous determination of dopamine (DA), acetaminophen (ACT), and bisphenol A (BPA). Several experimental conditions such as percent of modifier, pH of the solution, and square wave voltammetry parameters were optimized. The effective surface area of the electrodes was determined by chronocoulometry studies. The sensor demonstrated a linear plot of 7.0 × 10-6 – 5.0 × 10-4 M for DA, 3.0 × 10-5 – 5.0 × 10-4 M for ACT, and 3.0 × 10-6 – 5.0 × 10-4 M for BPA, with detection limit of 1.7 × 10-7 M, 1.8 × 10-7 M, and 1.4 × 10-7 M respectively. The interferences from 10 to 40-fold concentration of ascorbic acid, sodium salicylate, glucose, sucrose, glutamic acid, and captopril were negligible. The electrode also applicable for DA, ACT, and BPA determination in urine, pharmaceutical tablets, and plastic products samples with recoveries between 92.3 % and 109.7 %.