Selective Heavy Element Sensing with a Simple Host–Guest Fluorescent Array

Abstract

A simple three component array of host-fluorophore complexes is capable of sensitive and selective discrimination of heavy metal ions, including lanthanide and actinide salts in aqueous solution. Instead of applying optical sensors that only use "single-mode" detection, i.e., coordination of the metal to a specific ligand and monitoring the change in emission of an appended fluorophore, we exploit a series of host-fluorophore complexes that are affected by the presence of small amounts of metal ions in aqueous solution in different ways. Variable host-metal and host-guest-metal interactions lead to both turn-on and turn-off fluorescence sensing mechanisms, enhancing the discriminatory properties of the array. The limit of detection for certain metals is as low as 70 nM, and highly similar metals such as lanthanides and actinides can be easily distinguished at low micromolar concentrations in complex salt mixtures.

Single‐Component Chemical Nose with a Hemicyanine Probe for Pattern‐Based Discrimination of Metal Ions†

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Array-Based Discriminative Optical Biosensors for Identifying Multiple Proteins in Aqueous Solution and Biofluids

“…One way to achieve discriminative sensing is to develop multi-element sensor arrays, which are inspired by mimicking mammalian taste and smell systems and usually consist of multiple cross-reactive elements that generate a combined recognition pattern for each analyte (Stewart et al, 2013 ; Peveler et al, 2016 ; Rana et al, 2016 ). Another way to realize discriminative sensing is to fabricate an environment-sensitive sensor array, which is constructed by changing the solvents (Cao et al, 2014b , 2020 ; Smith et al, 2019 ), probe concentrations (Li et al, 2014 ), or pH values and ionic strengths (Liu et al, 2017 ; Tomita et al, 2017 ; Zhou et al, 2017 ; Lin et al, 2019 ). The third type of discriminative sensing is multi-wavelength cross-reactive single-system-based sensors, which use multiple wavelengths instead of multi-elements to provide response signals (Wu et al, 2011 ; Rout et al, 2012 ).…”

Pattern recognition of toxic metal ions using a single-probe thiocoumarin array

“…13,14 Array-based sensing methodologies have gained increasing prominence over the past decade. [15][16][17] Arrays offer advantages of highthroughput, fast, and straightforward analysis. Arrays typically use a number of distinct chemical probes in combination, and their combined fingerprint response allows the unambiguous identification of an analyte.…”