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Abstract The influence of strongly electron donating amino groups on a hydroxyaromatic 1,2,3‐triazolyl anion chemosensor was investigated with spectroscopic studies (ultraviolet‐visible [UV‐vis], fluorescence, and nuclear magnetic resonance [NMR]) and computational analyses. This work focused on2‐,3‐and4‐aminoderivatives of the parent molecule, 2‐(4‐phenyl‐1H‐1,2,3‐triazol‐1‐yl)phenol (PTP). The effect on signal‐output, selectivity, sensitivity, and the mechanism of response was explored. In all cases, the incorporation of the amino group enhances fluorescence during anion detection while retaining key properties (the receptor site, a blue‐fluorescent response, and the ability to detect F−, H2PO4−, and AcO−—strongest response to F−). Specifically, sensitivity to F−is impacted by the amino group's location. The2‐aminois most responsive to F−, more thanPTPand the other amino regioisomers. Results from this work are important for developing predictive, structure‐signal tuning models, which will be used in the targeted design of sensors based on thePTPscaffold.
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1,2,3-Triazoles: Controlled Switches in Logic Gate Applications
A 1,2,3-triazole-based chemosensor is used for selective switching in logic gate operations through colorimetric and fluorometric response mechanisms. The molecular probe synthesized via “click chemistry” resulted in a non-fluorescent 1,4-diaryl-1,2,3-triazole with a phenol moiety (PTP). However, upon sensing fluoride, it TURNS ON the molecule’s fluorescence. The TURN-OFF order occurs through fluorescence quenching of the sensor when metal ions, e.g., Cu2+, and Zn2+, are added to the PTP-fluoride ensemble. A detailed characterization using Nuclear Magnetic Resonance (NMR) spectroscopy in a sequential titration study substantiated the photophysical characteristics of PTP through UV-Vis absorption and fluorescence profiles. A combination of fluorescence OFF-ON-OFF sequences provides evidence of 1,2,3-triazoles being controlled switches applicable to multimodal logic operations. The “INH” gate was constructed based on the fluorescence output of PTP when the inputs are F− and Zn2+. The “IMP” and “OR” gates were created on the colorimetric output responses using the probe’s absorption with multiple inputs (F− and Zn2+ or Cu2+). The PTP sensor is the best example of the “Write-Read-Erase-Read” mimic.
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- PAR ID:
- 10472096
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Sensors
- Volume:
- 23
- Issue:
- 15
- ISSN:
- 1424-8220
- Page Range / eLocation ID:
- 7000
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/s23157000
