Application of Chitosan@Fe₃O₄ Nanoparticle-Modified Screen-Printed Graphene-Based Electrode for Simultaneous Analysis...

In this work, the development of screen-printed electrodes modified with chitosan-coated magnetite nanoparticles (CTS@Fe₃O₄/SPGNE) for the simultaneous determination of nitrite (NO₂^-) and ascorbic acid (AA^-) is presented. The study investigated various ratios of graphene to chitosan-coated magnetite nanoparticles (CTS@Fe₃O₄), as well as the optimal pH. These factors were examined due to their impact on the selectivity and sensitivity of the analysis. The results indicated that a graphene paste to CTS@Fe₃O₄ ratio of 16:1.0 g and a pH of 4 were optimal for the analysis of both NO₂^- and AA^-. Additionally, the behavior of the proposed electrode, its analytical performance, and interference studies were thoroughly examined. Furthermore, the CTS@Fe₃O₄/SPGNE electrode shows potential for the simultaneous determination of NO₂^- and AA^- in hydroponics and fruit juice samples.