Selective Determination of Acetaminophen in Presence of Ascorbic Acid at Poly (p-Methoxyphenol) Electrode

Abstract

In the present work, we discuss the modification of a gold electrode with p-methoxyphenol and its application as a sensor for acetaminophen (ACP) in a phosphate buffer solution (pH = 7.4). The modified electrode was subsequently employed to determine acetaminophen in the presence of ascorbic acid (AA) using differential pulse voltammetry (DPV). The peak positions and relative sensitivity of ACP/AA were influenced by the potential window used during polymerization. For polymerization between 0 and 1.0 V, the peak potentials recorded in the phosphate buffer solution (pH = 7.4) were 488 mV for ACP and 280 mV vs. Ag/AgCl for AA. Furthermore, the effects of pH and electrolyte type on the linearity range and detection limit were investigated. The high selectivity and sensitivity for ACP were attributed to charge discrimination and analyte accumulation. The detection limit for the 3σ-test was determined to be 0.2 nM. This study highlights the potential of the modified gold electrode for selective and sensitive detection of acetaminophen, even in the presence of interfering substances such as ascorbic acid. The optimization of polymerization conditions and the comprehensive analysis of pH and electrolyte effects contribute to the electrode's superior performance.