Enhanced Performance of CNT‐doped Imine Based Receptors as Fe(III) Sensor Using Potentiometry and Voltammetry

Abstract

A highly sensitive and selective potentiometric and voltammteric assay for the detection of Fe3+ using (E)‐3‐((2‐(2‐(2‐aminoethylamino) ethylamino) ethylimino)methyl)‐4H‐chromen‐4‐one (IFE(III)) ionophore was developed. To demonstrate the ion‐to‐electron transfer ability of MWCNT, these were incorporated in the ion‐selective membrane and response characteristics of Fe3+ electrode was compared with those of the traditional ion selective electrode. The electrode showed an improved Nernstian slope, lower detection limit, response time of less than 5 s and working in a pH range of 3.0 to 8.0. Differential pulse voltammetric studies were performed for IFE(III)‐Fe3+ complex in DMSO solvent medium at glassy carbon (GC) electrode. A linear relationship between the cathodic peak current and concentration of Fe3+ was observed in the range of 1.6×10−5 to 4.4×10−5 mol/L with a detection limit of 5.2×10−8 mol/L. The electrode shows remarkable selectivity for Fe3+ ions over alkali, alkaline earth, transition and heavy metal ions. The optimized electrode was successfully applied for the determination of Fe3+ ion in different real‐life samples using potentiometric technique. Theoretical calculations were used to support the complexation behavior of Fe3+ with IFE(III).

Potentiometric Sensing

“…) ethylamino) ethylimino)methyl)-4H-chromen-4-one, as an ionophore for potentiometric Fe 3+ sensing. 142 The prepared Fe 3+ -selective electrode with an inner reference solution demonstrated a 21 mV/ decade slope in the concentration range of 10 −6 −10 −1 M. Surprisingly, the authors reported that the additional doping of the membrane matrix with carboxylated MWCNTs improved the lower detection limit of their sensor by almost an order of magnitude. Besides, the MWCNT doping also lowered the selectivity coefficient values for Fe 3+ over different cations by 1−2 orders of magnitude.…”

“…Mittal et al synthesized and tested an imine-based ligand, ( E )-3-((2-(2-(2-aminoethylamino) ethylamino) ethylimino)­methyl)-4 H -chromen-4-one, as an ionophore for potentiometric Fe 3+ sensing . The prepared Fe 3+ -selective electrode with an inner reference solution demonstrated a 21 mV/decade slope in the concentration range of 10 –6 –10 –1 M. Surprisingly, the authors reported that the additional doping of the membrane matrix with carboxylated MWCNTs improved the lower detection limit of their sensor by almost an order of magnitude.…”

Low-cost Pencil-Graphite Multi-electrodes for Simultaneous Detection of Iron and Copper

“…It can be seen in Table 2 that interferences with metal ions including Na + , K + , Mn 2+ , Zn 2+ , Ni 2+ , Co 2+ Fe 2+ , and Cr 3+ are negligible for the developed electrodes since the selectivity coefficient values were lower than 1 (22).…”

Selective Detection of Fe3+ by Nitrogen–Sulfur-Doped Carbon Dots Using Thiourea and Citric Acid

“…Therefore, how to quickly and accurately detect Fe 3+ in the environment has always attracted much attention [13]. At present, there are many detection methods for Fe 3+ , including potential voltammetry [14], atomic absorption spectrometry [15], and colorimetric methods [16]. However, most of these testing methods require expensive tools or instruments, and the more complex testing processes also put forward higher technical requirements for sample processing and operation.…”