High-Sensitivity Detection of Iron(III) by Dopamine-Modified Funnel-Shaped Nanochannels

Abstract

Iron as an essential trace element in the human body participates in various biological processes. The demand for efficient and sensitive detection of Fe has drawn wide attentions. Inspired by biological nanochannels, a high-sensitivity, economic, and recyclable Fe detection method is proposed by using dopamine (DOPA)-modified funnel-shaped nanochannels. Along with the Fe concentration changing, different Fe-DOPA chelates are generated in the channel, which affect the wettability and charge distribution of the pore surface, resulting in a change of ionic current through the nanochannels. Meanwhile, the funnel-shaped nanochannel applied in this work with a narrow cylindrical segment (a diameter close to 10 nm) as the critical section can enhance the sensing ability to the ultra-trace level (down to 10 M). We expound the mechanism and feasibility of this method and anticipate that the system can be a good example to design highly sensitive and stable ion detection devices.

Biomolecule‐Functionalized Solid‐State Ion Nanochannels/Nanopores: Features and Techniques

“…It is well known that the biomolecules such as DNA, aptamers, peptides, amino acids, and enzymes often contain amino groups, which facilitates the connection of biomolecules onto the surface of polymer nanochannels/nanopores. As shown in Figure a the dopamine (DOPA) was attached to the inner wall of funnel‐shaped PET nanochannels by the typical two‐step method with amide linkage . However, when the functionalization processes of nanochannels/nanopores have to rely on other functional groups of a biomolecule rather than NH 2 , the thiol‐group (SH), for example, the typical two‐step method would not work.…”

“…Functionalization of polymer nanochannels/nanopores by direct bonding: a) The functionalization of funnel‐shaped FET nanochannel with dopamine (DOPA) by the typical two‐step method. Reproduced with permission . Copyright 2018, American Chemical Society.…”

“…As shown in Figure 13a the dopamine (DOPA) was attached to the inner wall of funnelshaped PET nanochannels by the typical two-step method with amide linkage. [95] However, when the functionalization processes of nanochannels/nanopores have to rely on other functional groups of a biomolecule rather than NH 2 , the thiol-group (SH), for example, the typical two-step method would not work. And then an improved version toward the typical two-step method is necessary.…”

Biomimetic stimuli‐responsive nanochannels and their applications

“…In addition to the above monovalent cations responsive artificial nanochannels, several bivalent and multivalent cations responsive biomimetic nanochannels have also been constructed successfully . Our group demonstrated a copper‐responsive nanochannel system with controllable ion transport properties by immobilizing a Cu 2+ ‐responsive self‐cleaving DNAzyme into PET conical multi‐nanochannels (Fig.…”

“…Most recently, Wen's group reported a high sensitivity and recyclable Fe (III)‐responsive artificial nanodevice by immobilizing dopamine (DOPA) in funnel‐shaped nanochannels (Fig. E) . In the presence of Fe(III), along with the ratio of DOPA and Fe(III), different Fe(III)‐DOPA chelates were generated on the surface of nanochannels.…”