Ultrasensitive SWASV-based electrochemical determination of total arsenic in environmental and biological matrices using a cauliflower-like AuAg/GCE: Towards public health risk assessment

Arsenic contamination is a major threat to public health and environmental protection, necessitating the development of a rapid, sensitive, and reliable analytical approach for its monitoring. Here, a cauliflower-like gold‑silver nanostructured modified glassy carbon electrode (CF-AuAg/GCE) was fabricated as a novel electrochemical sensor for ultrasensitive determination of total arsenic using square-wave anodic stripping voltammetry (SWASV). The properties of the proposed sensor were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and square-wave anodic stripping voltammetry. The CF-AuAg/GCE has a high electrochemically active surface area (ECSA) and good electrical conductivity for efficient arsenic determination. Meanwhile, the proposed sensor exhibits excellent anti-interference properties, repeatability, long-term stability, and reproducibility. Under optimal conditions, peak current was proportional to arsenic concentration over 0 to 300 μg/L linear dynamic range (LDR), with a limit of detection (LOD) of 0.06 μg/L. Finally, CF-AuAg/GCE was successfully applied to determine total arsenic in industrial wastewater, medicinal herbs (licorice root, ginseng root, astragalus root, and chrysanthemum flower), and artificial saliva, yielding high recoveries and good practicability. The excellent electrochemical sensing performance, with a low detection limit and high sensitivity at the μg/L level, is attributed to the unique structure of CF-AuAg/GCE and fast electron-transfer kinetics. Therefore, CF-AuAg/GCE is a robust and promising approach for arsenic determination in environmental and biological matrices. Download: Download high-res image (150KB) Download: Download full-size image