Emerging contaminants, such as acetaminophen (APAP) and bisphenol A (BPA), pose significant threats to environmental and human health due to their widespread presence and potential toxicity. The development of sensitive and selective analytical methods for their detection in aqueous environments is crucial. Electrochemical sensors offer a promising avenue due to their inherent simplicity, rapid response, and potential for on-site monitoring. In this study, we present the fabrication and application of a novel electrochemical sensor based on a glassy carbon electrode (GCE) modified with a hierarchical bimodal nanoporous gold (hBNPG) structure (hBNPG@GCE) for the detection of APAP.
The hBNPG material was synthesized and characterized using Brunauer–Emmett–Teller (BET) analysis, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX), confirming its high surface area and nanoporous properties.
The electrochemical behavior of APAP and BPA at the hBNPG@GCE was investigated using cyclic voltammetry (CV) in phosphate-buffered saline (PBS). Square wave voltammetry (SWV) was then employed for quantitative analysis. The hBNPG@GCE exhibited significantly enhanced electrocatalytic activity towards the oxidation of APAP, achieving a limit of detection (LOD) of 100nM and a limit of quantification (LOQ) of 544 nM for acetaminophen. Interference studies conducted in the presence of common inorganic ions found in water demonstrated good selectivity for APAP detection. Furthermore, the modified electrode demonstrated its capability for the simultaneous detection of both APAP and BPA in the same electrolyte solution. Reproducibility studies were conducted by performing three consecutive measurements on the same electrode.
These results highlight the potential of the hBNPG@GCE as a highly sensitive and selective electrochemical sensor for detecting emerging contaminants like APAP. The hierarchical bimodal nanoporous structure of gold offers a large surface area and enhanced mass transport, contributing to the improved analytical performance. This sensor design holds promise for applications in environmental monitoring and water quality assessment.
