Nonenzymatic Electrochemical Sensing of Glucose Using Hydrothermally Synthesized High-Specific-Surface-Area SnO₂...

The successful synthesis of high-surface-area SnO₂ nanoparticles with a spherical surface morphology and an average size of 16 nm was carried out using a hydrothermal chemical approach. The characterization of the as-prepared nanoparticles was carried out using XRD, TEM, FESEM, EDX, and UV-visible DRS techniques. The BET surface area of the SnO₂ nanoparticles was found to be 94.2 m²/g. Electrochemical analysis using cyclic voltammetry, chronoamperometry, and linear sweep voltammetry demonstrated the sensitivity of the nanoparticles toward glucose detection, showing a linear response from 0.25 to 3.0 mM and a low detection limit of 0.11 mM. The chronoamperometric analysis showed a rapid response of an electrode with the successive addition of different glucose concentrations. The SnO₂-modified electrode exhibited a rapid, stable, and selective response to glucose, with only ∼15% signal loss over 15 days of intermittent use. Furthermore, SnO₂ shows good selectivity toward glucose molecules with low interference from glucose analogues such as dopamine and ascorbic acid. These findings suggest the potential application of pristine SnO₂ nanostructures as efficient nonenzymatic electrochemical sensors for glucose monitoring.