Novel Tin-Oxide Nanoparticle-Modified Glassy Carbon Electrode for the Highly Selective and Simultaneous Detection of Dopamine, Uric Acid, and Ascorbic Acid

Abstract

A novel electrochemical sensor has been developed using tin oxide nanoparticles (SnOxNPs)- modified glassy carbon electrodes (GCEs) for the simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). Hydrothermal synthesis produced SnOxNPs, which were analyzed using several structural characterization techniques, confirming their nanoscale dimensions and crystalline structure. The electrocatalytic performance of SnOxNPs-GCE improved due to enhanced electrical conductivity and better interactions at the electrode surface. The enhancement in analytical response stems from well-defined interactions between the analytical compounds and the SnOxNPs-GCE surface during electrochemical measurements. The electrode demonstrated low detection limits of 0.148 µM, 0.544 µM, and 12.56 µM for DA, UA, and AA, respectively. The constructed sensor effectively resisted external interference from substances such as glucose, citric acid, and L-cysteine, as well as urea and metal ions (Na+, Mg2+, and Ca2+). This proposed electrode also exhibits excellent analytical characteristics, including high sensitivity, stability, and reproducibility toward DA, UA, and AA.