Synergistic Effect of Biosynthesized NiO Nanoparticles and Functionalized Dialdehyde <i>γ</i>-cyclodextrin Schiff Base on the Voltammetric Determination of Bisphenol A

Bisphenol A (BPA) is an endocrine-disrupting compound widely found in plastics, posing serious environmental and health concerns. In this paper, a highly sensitive and selective voltammetric sensor for BPA determination is developed, utilizing biosynthesized nickel oxide nanoparticles (NiO NPs) and a functionalized dialdehyde γ -cyclodextrin camphor thiazole amine Schiff base (DA- γ -CD-CTI). NiO NPs were synthesized via a green approach using Coriandrum sativum extract, providing eco-friendly, cost-effective, and highly conductive nanomaterials. The DA- γ -CD-CTI Schiff base was employed to enhance molecular recognition and improve the sensor’s stability and selectivity. The modified electrode exhibited excellent electrochemical performance, enhanced electron transfer, increased surface area, and superior adsorption capacity. Under optimal conditions, the developed sensor demonstrated a wide linear range (0.03–4.0 μM), a low detection limit (8.2 nM), and high sensitivity for BPA detection. The proposed method was successfully applied to real sample analysis, showing good recovery (95.60% to 100.67%) and reproducibility. The combination of biosynthesized NiO nanoparticles and functionalized γ -cyclodextrin Schiff base provides a promising approach for developing advanced electrochemical sensors for food safety applications.