Electrodeposited β-Ni(OH)₂ as Sensing Platform for Spermine and Spermidine in Black Chickpeas

Sensing spermine and spermidine in food matrices remains a challenge due to their structural similarity and non-redox nature. In this study, β-Ni(OH)₂ was electrochemically deposited onto a glassy carbon (GC) electrode using amperometry technique by applying a cathodic potential of − 1.5 V for 10 s. The physicochemical properties of the β-Ni(OH)₂/GC electrode, including surface morphology and chemical composition, were characterized using field emission scanning electron microscopy (FE-SEM) and X-ray photoelectron spectroscopy (XPS), respectively. The sensing behavior of the β-Ni(OH)₂/GC electrode towards spermine and spermidine was evaluated in a 0.1 M NaOH. Voltammetry analysis revealed that the β-Ni(OH)₂/GC electrode could effectively discriminate spermidine from spermine and vice versa. They exhibited a wide response range from 1.0 to 500.0 µM for both analytes, with detection limits of 0.17 µM for spermine and 0.34 µM for spermidine. Additionally, it demonstrated high sensitivity, with values of 5.0 × 10⁻² µA µM⁻¹ for spermine and 4.7 × 10⁻² µA µM⁻¹ for spermidine. The electrodeposited β-Ni(OH)₂ exhibited good stability and reproducibility for sensing spermine and spermidine, even in the complex matrix of black chickpea extract. Thus, the electrodeposited β-Ni(OH)₂/GC electrode offers a reliable approach for ensuring food quality.