Reversal of a Fluorescent Fluoride Chemosensor from Turn-Off to Turn-On Based on Aggregation Induced Emission Properties

Abstract

Here we present a new approach for the development of fluoride chemosensors taking advantage of aggregation induced emission (AIE) properties. Although AIE-based chemosensors have been described, they rely primarily on the analyte causing aggregation and hence fluorescence. We propose a new concept in the use of AIE for the development of fluorescent sensors. Our hypothesis is based on the fact that a turn-off chemosensor in solution can be transformed into turn-on in the solid state if the properties of ACQ and AIE are properly combined between the fluorescent molecules involved. To demonstrate this hypothesis, we have selected a fluorescent chemosensor for the fluoride anion with a conjugated structure of bis(styryl)pyrimidine that, while showing turn-off behavior in solution, becomes turn-on when it is brought to the solid state. We have also combined it with the advantages of a detection system based on the microfluidic paper-based analytical devices (μPAD). The system is fully characterized spectroscopically both in solution and in the solid state, and quantum mechanical calculations were performed to explain how the sensor works. The prepared device presents a high sensitivity, with no interference and with an LoD and LoQ that allow determination of fluoride concentrations in water 2 orders of magnitude below the maximum allowed by WHO.

Metal–organic framework-derived photoelectrochemical sensors: structural design and biosensing technology

“…112,113 However, luminescence switching takes on the ''turn-off'' type are difficult to quantitative signal decrease and ensure its sensing sensitivity. [114][115][116][117] To address this issue, Yan et al prepared a luminescent Eu-doped MOF for the quantitative analysis of urinary chemical carcinogens. 98 The mechanism for 1-hydroxytryptamine (1-HP) detection depends on the ligand-to-metal resonance energy transfer.…”

Trimeric and Tetrameric Cationic Styryl Dyes as Novel Fluorescence and CD Probes for ds-DNA and ds-RNA

“…This building block can be found among several antiviral, antifungal [ 15 , 16 ], antibacterial [ 17 ], and anticancer medicines [ 18 ] and inhibitors of HIV integrase [ 19 ]. This class of compounds has attracted a lot of interest because of its electroluminescence and photochromic capabilities, which might make them useful in optical devices [ 20 , 21 ] or as sensors [ 22 ] and biosensors [ 23 , 24 , 25 ]. Further, a 4-aminostyryl derivative of 6-methylquinoline showed potential therapeutic and diagnostic characteristics against Alzheimer’s disease [ 26 ].…”

In Situ Ni(II) Complexation Induced Deprotonation of Bis-Thiourea-Based Tweezers in DMSO–Water Medium: An Approach toward Recognition of Fluoride Ions in Water with Organic Probe Molecules

“…However, most of these methods involve sophisticated instrumentation requiring expertise knowledge and are not cost-effective for routine monitoring, specifically in remote areas. Among these, the ISE is relatively cost-effective and the most widely used for the assessment of the F – ion in groundwater, but the presence of the Al­(III) ion in water severely undermines the detection efficiency of F – through the formation of an Al­(III)–fluoride complex. , On the contrary, optical methods (colorimetric and fluorometric) are potential alternatives because of their easy operation and higher sensitivity. − The SPADNS-zirconium method has been one of the standard colorimetric estimation methods for the fluoride ion in aqueous medium. Although the performance of this method is satisfactory, the method is susceptible to interference by Al 3+ , Cl – , Fe 3+ , SO 4 2– , and PO 4 3– ions, demanding the removal of the interfering ions from the sample prior to estimation .…”