Biogenic-magnesium oxide nanoparticles from Bauhinia variegata (Kachnar) flower extract: a sustainable electrochemical approach for vitamin-B12 determination in real fruit juice and milk

Abstract

Vitamin-B₁₂ (Vit-B₁₂) is an essential organo-metallic micronutrient necessary for the proper functioning of the human body. Factors such as convenient lifestyle, starvation, and genetic defects are major contributing reasons for Vit-B₁₂ deficiencies, which can lead to increased morbidities. Today's challenge lies not only in advancing the diagnosis of Vit-B₁₂ but also in making it sustainable. In this context, the electrochemical detection of Vit-B₁₂ was performed utilizing hydrothermally synthesized biogenic-magnesium oxide nanoparticles (B-MgO-NPs) derived from Kachnar (Bauhinia variegata) flower extract. After the synthesis of B-MgO-NPs, XRD, FTIR, Raman, UV-vis, XPS, SEM, EDX, and HR-TEM techniques were used to determine their structural and morphological characteristics. Electrochemical analysis results suggest that the fabrication of electrophoretically deposited B-MgO NPs on an indium tin oxide (ITO) glass substrate-based bioelectrode has more current density when compared with bare ITO. Moreover, it was also evident from cyclic voltammetry analysis that the fabricated bioelectrode exhibited sensitivities of 2.96 × 10⁻³ and 0.17 × 10⁻³ mA pM⁻¹ cm⁻² in a linear concentration range of 1–100 and 200–1200 pM, respectively. Furthermore, it demonstrated a low limit of detection (LOD) of 0.0884 pM and a limit of quantification (LOQ) of 1.3462 pM. Apart from standard sample analysis, the B-MgO NP/ITO bioelectrode was used to quantify real samples, such as preservative juice, fresh milk, orange juice, and vitamin-B₁₂ tablets. Thus, the fabricated bioelectrode is reliable for real sample analysis. This study is important in the field of Vit-B₁₂ detection, aiding in quality control, product development, and nutritional assessments.