Work

Novel Discrete and Imprinted Fluoride‐Selective Sensors: Bridging the Gap from DMSO to Aqueous Samples

Year: 2024

Type: article

Abstract: Fluoride in drinking water has beneficial or harmful health effects depending on its concentration. This highlights the need for new low‐cost and portable sensors capable of in situ monitoring of F − ions. Unfortunately, achieving high levels of water compatibility and fluoride specificity remains a challenge. Here, four new urea‐based discrete sensors are prepared and characterized. The sensors containing anthracenyl‐ ( 5 ) and 9H‐fluorenyl‐ ( 7 ) signaling units exhibit intense luminescent emissions in dimethyl sulfoxide, the former being particularly sensitive and selective to fluoride. In water, 5 displays a superior sensitivity (871 M −1 ) and a detection limit (8 µ m ) below international guidelines, albeit with cross‐sensitivity to H 2 PO 4 ‾. To enhance the performance, 5 and 7 are embedded into a fluoride‐imprinted polymeric matrix to give solid‐state sensors ( 5P and 7P , respectively). 5P shows good sensitivity (360 M −1 ) and specificity in water. Besides, it has a low detection limit (35 µ m ) and a response linear range (118–6300 µ m ) encompassing the limit established by the Environmental Protection Agency (211 µ m ). Furthermore, 5P also displays good reusability and adequate recovery values in real‐sample testing (102 ± 2%), constituting the first example of a low‐cost anion‐imprinted polymeric probe tailored for the selective sensing of fluoride in aqueous samples.

Source: Small

DOI: 10.1002/smll.202402696