Poly(carbazole-co-1,4-dimethoxybenzene): Synthesis, Electrochemiluminescence Performance, and Application in Detection of Fe3+

Abstract

In this study, four polycarbazole derivatives (PCMB-Ds) with different alkyl side chains were designed and synthesized via Wittig–Horner reaction. A novel solid-phase electrochemiluminescence (ECL) system was prepared by immobilizing PCMB-D on an indium tin oxide (ITO) electrode with polyvinylidene fluoride (PVDF) in the presence of tripropylamine (TPrA). It could be found that the increase in alkyl side chain length had little effect on the ECL signal of PCMB-D, while the increase in the degree of polymerization (DP) greatly enhanced the ECL signal. Furthermore, the P-3/ITO ECL sensor based on the polyoctylcarbazole derivative (P-3) with the best ECL performance was successfully constructed and detected Fe3+ under the optimal experimental conditions. The ECL signal steadily diminished with the increased concentration of Fe3+ because of the competition and complexation between Fe3+ and P-3 under the condition of pH 7.4. This P-3/ITO platform could realize a highly sensitive and selective detection of Fe3+ with a wide detection range (from 6 × 10−8 mol/L to 1 × 10−5 mol/L) and low detection limit of 2 × 10−8 mol/L, which could allow the detection of Fe3+ in multiple scenarios, and would have a great application prospect.

Electrochemiluminescence Systems for Metal‐Ion Detection: A Systematic Review

“…Fe(III) was measured in the range of 3×10 À 7 -2.5×10 À 8 M and the LOD value was obtained about 4.1×10 À 10 M. Moreover, Hou et al developed a poly(octylcarbazole-co-1,4-dimethoxybenzene) (P-3) coating ITO electrode as ECL emitter in the solution of TPrA as co-reactant. [35] It was found that the ECL signal intensity constantly reduced with the increase of Fe(III). Two pathways were proposed to explain the reduced ECL signal: the competition between Fe(III) and P-3 for the TPrA co-reactant or the complexation between Fe(III) and P-3 that consumed the luminescent materials.…”

“…Au@SiO 2 nanomembrane and polycarbazole derivatives were immobilized onto the surface of the ITO electrode to detect Hg(II) and Fe(III), respectively. [35,66] ITO electrode was also modified by poly(aniline-luminol)/graphene oxide/chitosan (P(Ani-Lu)/GO/ CS) to detect Hg(II). High conductivity and large specific surface area of polyaniline facilitate the charge transfer process on the electrode interface; hence, the modified electrode has lower impedance and smaller diameter of the semicircular.…”

“…Fe(III) was measured in the range of 3×10 −7 –2.5×10 −8 M and the LOD value was obtained about 4.1×10 −10 M. Moreover, Hou et al. developed a poly(octylcarbazole‐co‐1,4‐dimethoxybenzene) (P‐3) coating ITO electrode as ECL emitter in the solution of TPrA as co‐reactant [35] . It was found that the ECL signal intensity constantly reduced with the increase of Fe(III).…”

“…Moreover, several studies have developed modified ITO electrodes to design the solid‐phase ECL system. Au@SiO 2 nanomembrane and polycarbazole derivatives were immobilized onto the surface of the ITO electrode to detect Hg(II) and Fe(III), respectively [35,66] . ITO electrode was also modified by poly(aniline‐luminol)/graphene oxide/chitosan (P(Ani‐Lu)/GO/CS) to detect Hg(II).…”

“…Their measurement values reveal excellent sensitivity and very low detection limits compared to other measuring instruments, namely 3.3×10 À 16 M for Hg(II), [31] 1.9×10 À 16 M for Pb(II), [32] and 3.33×10 À 15 M for Cu(II), [33] as shown in Table 1. In addition, other metals are also being studied for ECL system applications, such as Cd(II), [34] Fe(III), [35] Co(II), [36] Cr(III), [37] Cr(VI), [38] Ag(I), [39] Ni(II) [40] and As(III). [41] Furthermore, the ECL system demonstrates high selectivity for metal measurement, providing a distinctive and specific signal of the luminophore used.…”