Green synthesis of cyclodextrin-capped AuNPs decorated on polystyrene microspheres for a furazolidone-responsive electrode

Herein, a glassy carbon electrode modified with polystyrene microspheres decorated with β-cyclodextrin-capped gold nanoparticles (denoted P/CD@AuNPs/GCE) was designed to scrutinize the electrochemical sensing behavior of furazolidone (FZ) for the first time. Various spectroscopic and microscopic techniques were applied to characterize the physiochemical attributes of the prepared P/CD@AuNPs. Compared to bare GCE, P/CD@AuNPs/GCE unveils higher peak currents with lower peak potentials. Due to the presence of a combination of monodispersed CD@AuNPs on the PS surface, it benefits from high electrical conductivity, ghost-guest interaction, and rapid electron transfer ability, thus warranting competent electrocatalytic performance. The sensor showed great sensitivity, wide linear range (0.05–715 μM), low limit of detection (2.03 nM), superior selectivity, good repeatability, and reproducibility (1.29%) toward FZ detection. The sensor was successfully validated on a real human blood serum sample, and excellent recovery values (90%−101.2%) were achieved. The devised sensor offers a competent and promising sustainable electrocatalyst for monitoring FZ in human blood serum.