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Abstract In this review, recent research efforts that aimed at developing nanopore sensors for detection of metal ions, which play a crucial role in environmental safety and human health, are highlighted. Protein pores use three stochastic sensing‐based strategies for metal ion detection. The first strategy is to construct engineered nanopores with metal ion binding sites, so that the interaction between the target analytes and the nanopore can slow the movement of metal ions in the nanochannel. Second, large molecules such as nucleic acids and especially peptides can be utilized as external selective molecular probes to detect metal ions based on the conformational change of the ligand molecules induced by the metal ion–ligand chelation/coordination interaction. Third, enzymatic reactions can also be used as an alternative to the molecule probe strategy in the situation that a sensitive and selective probe molecule for the target analyte is difficult to obtain. On the other hand, by taking advantage of steady‐state analysis, synthetic nanopores mainly use two strategies (modification and modification‐free) to detect metals. Given the advantages of high sensitivity and selectivity, and label‐free detection, nanopore‐based metal ion sensors should find useful application in many fields, including environmental monitoring, medical diagnosis, and so on.
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Detection of Ethylene with Defined Metal Complexes: Strategies and Recent Advances
Abstract Despite its relative simplicity, ethylene is an interesting molecule with wide‐ranging impact in modern chemistry and biology. Stemming from ethylene's role as a critical plant hormone, there has been significant effort to develop selective and sensitive molecular sensors for ethylene. Late transition metal complexes have played an important role in detection strategies due to ethylene's lack of structural complexity and limited reactivity. Two main approaches to ethylene detection are identified: (1) coordination‐based sensors, wherein ethylene binds reversibly to a metal center, and (2) activity‐based sensors, wherein ethylene undergoes a reaction at a metal center, resulting in the formation and destruction of covalent bonds. Herein, we describe the advantages and disadvantages of various approaches, and the challenges remaining for sensor development.
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- Award ID(s):
- 1900482
- PAR ID:
- 10401431
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Analysis & Sensing
- Volume:
- 3
- Issue:
- 2
- ISSN:
- 2629-2742
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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