Synergistic Effect of Bio‐Inspired Nanochannels: Hydrophilic DNA Probes at Inner Wall and Hydrophobic Coating at Outer Surface for Highly Sensitive Detection

Abstract

During the past few decades, bio‐inspired nanochannels have been well developed and applied in biosensing, energy transfer, separation, and so on. Here, inspired by the synergistic effect of biological nanopores, biomimetic solid‐state nanochannels with hydrophilic DNA probes at the inner wall (DNA@IWHydrophilic) and hydrophobic coating at the outer surface (None@OSHydrophobic) are designed. To demonstrate their prompted sensing properties, Hg2+ and its specific probe are selected as target and hydrophilic DNA probes, respectively. Compared with the traditional solid‐state nanochannels with hydrophilic probes distributed on both the inner wall and outer surface, the nanochannels with DNA@IWHydrophilic+None@OSHydrophobic significantly decrease the limit of detection (LOD) by 105‐fold. The obvious improvement of sensitivity (with LOD of 1 nM) is attributed to the synergistic effect: None@OSHydrophobic results in the nanochannel's effective diameter decrease and DNA@IWHydrophilic induces a specific sensing target. Meanwhile, nanomolar detection of Hg2+ in human serum and in vivo fish muscle are achieved. Through molecular dynamics simulation, the synergistic effect can be confirmed by ion fluxes increasement; the relative carbon nanotube increases from 135.64% to 135.84%. This work improves the understanding of nanochannels’ synergistic effect and provides a significant insight for nanochannels with improved sensitivity.

Inner Wall and Outer Surface Distinguished Solid-State Nanopores for Sensing

“…We independently modified hydrophilic DNA probes at the inner wall and a hydrophobic coating at the outer surface. 42 Compared with the traditional solid-state nanopores with the entire surface modification with hydrophilic probes, our independently modified nanopores significantly reduce the detection limit of Hg 2+ by 10 5 -fold. The significant improvement in sensitivity is attributed to the synergistic effect: hydrophobic FE OS results in a decrease in the effective diameter of the pore, and hydrophilic FE IW induces a specific recognition for Hg 2+ .…”

“…In addition, the sensor shows good specificity for four types of interfering bacteria. We independently modified hydrophilic DNA probes at the inner wall and a hydrophobic coating at the outer surface . Compared with the traditional solid-state nanopores with the entire surface modification with hydrophilic probes, our independently modified nanopores significantly reduce the detection limit of Hg 2+ by 10 5 -fold.…”

In situ growth of metal–organic frameworks in nanochannels for highly sensitive microcystin-LR detection

“…24 Among the numerous kinds of solid-state nanochannels, maturely commercialized anodic aluminum oxide (AAO) with an arrayed nanochannel structure and adjustable diameter in the range of 20–300 nm has been widely adopted to construct solid-state nanochannel-based sensing systems. 18 For example, Lu et al modified AAO nanochannels with ZnS for tetracycline detection. A limit of detection (LOD) of 1 mM was realized.…”

“…In recent decades, solid-state nanochannels have attracted extensive attention due to their adjustable structure, physicochemical stability, and good mechanical properties. [14][15][16][17] Through modification with the target DNA aptamer as a specific probe in advance, solid-state nanochannel-based sensing systems have demonstrated great sensitivity and specificity for sensing various analytes, including Hg 2+ , 18 Cr 3+ , 19 ATP, 20 miRNA, 21 chloramphenicol, 22 tyrosine phosphorylation, 23 and MCF-7 cells. 24 Among the numerous kinds of solid-state nanochannels, maturely commercialized anodic aluminum oxide (AAO) with an arrayed nanochannel structure and adjustable diameter in the range of 20-300 nm has been widely adopted to construct solid-state nanochannel-based sensing systems.…”

Engineering Sandwiched Nanochannel Aptasensor for Efficiently Screening Cancer Cells

“…Artificial solid‐state nanochannels have been widely studied in the field of biological analysis due to their superior advantages of special nanoconfined space, excellent stability, and easy modification, which endows rapid and sensitive detection performance [15–21] . In recent years, pioneering scientists subtly combined nanochannels with various nanomaterials to regulate the nanochannels’ properties and endow them with fascinating capabilities.…”