Sulfathiazole-based novel azo dye as electrode modifier for carbon paste electrode for selective detection of uric acid and paracetamol: synthesis, characterization, and fluorescence studies
摘要
This research explores the synthesis of new azo dye derived from sulfathiazole, with the aim of developing potential applications in electrochemistry. The prepared structure was elucidated using spectroscopic techniques, including NMR, IR, UV–Vis, fluorescence, mass spectrometry, and elemental composition studies. The voltammetric techniques were applied to assess the sensor performance of the synthesized sulfathiazole azo dye. Electrochemical impedance spectroscopy was also employed to investigate the electrochemical response of the sulfathiazole-based azo dye-modified carbon paste electrode (STDMCPE). The STDMCPE was further utilized to examine a range of electrochemical characteristics, including the influence of scan rate, pH, and analyte concentration, as well as to evaluate potential interferences. The electrochemical process for uric acid was found to be diffusion-controlled, whereas paracetamol exhibited adsorption-controlled behavior. The STDMCPE sensor demonstrated a linear response for uric acid and paracetamol over the 10 to 60 µM concentration ranges, with calculated detection limits of 13.1955 × 10⁻7 M and 5.8482 × 10–6 M, respectively. The oxidation peak potentials of paracetamol and uric acid were separated by 0.249 V and 0.313 V using differential pulse voltammetry and cyclic voltammetry, respectively. This separation indicates the ability of the modified electrode to detect both uric acid and paracetamol selectively. Further, the performance of the fabricated electrochemical sensor was validated by assessing its reproducibility and stability, demonstrating satisfactory results.
Graphical abstract