Ethylenediaminetetraacetic acid intercalated MgAl-layered double-hydroxides nanocomposite as an efficient platform in the development of electrochemical sensor for the detection of iron (II)

The significance of iron in maintaining physiological homeostasis in the human body is well recognized. However, the presence of unbound iron, specifically the non-transferrin bound iron (NTBI), can potentially induce tissue damage in crucial organs, such as the heart, kidney, and liver. Consequently, there arises a critical need to establish a sensing platform with the capability of detecting exceedingly low concentrations of iron (II). To address this imperative, a layered double-hydroxide (LDH) structure comprising Mg 2+ and Al 3+ with ethylenediaminetetraacetic acid (EDTA) intercalated between the layers has been successfully synthesized. The proposed methodology involves the utilization of a differential pulse voltammetric detection approach to identify Fe 2+ on an EDTA-MgAl LDHs composite-modified glassy carbon electrode. Scanning Electron Microscopy (SEM) analysis of the EDTA-MgAl LDHs revealed the stratified structure of sheets with thicknesses ranging from 95 to 160 nm. Voltammetry studies further demonstrated the effective Fe 2+ capturing ability of EDTA and confirmed the existence of multi-layered MgAl LDHs, which contribute to the electrocatalytic oxidation of Fe 2+ to Fe 3+ . The developed sensor exhibited an elevated sensitivity (0.061 µA µM −1 ) towards Fe 2+ and a wide linear detection ranges from 0.1 to 102.1 µM, with an exceptionally low detection limit of 50 nM. Furthermore, the applicability of a two-segmented piecewise linear function to estimate the breakpoint Fe 2+ concentration, above and below which the sensor's response behaviour changes, was assessed for the direct determination of Fe 2+ in a 0.1 M KCl solution. In conclusion, the developed sensor possesses several advantageous attributes, including a rapid response time, effective Fe 2+ capturing ability, electrocatalytic capability, wide linearity, and resistance to interference from other metal ions. These characteristics collectively render it a highly promising and efficient sensing platform for diverse Fe 2+ detection applications. Graphical abstract