饮用水中的氟化物根据其浓度对健康有益或有害。这凸显了对能够原位监测F-离子的新型低成本便携式传感器的需求。不幸的是,实现高水平的水相容性和氟化物特异性仍然是一个挑战。这里,制备并表征了四种新的基于尿素的离散传感器。含有蒽基-(5)和9H-芴基-(7)信号单元的传感器在二甲基亚砜中表现出强烈的发光发射,前者对氟化物特别敏感和有选择性。在水中,图5显示出较高的灵敏度(871M-1)和低于国际准则的检测极限(8µm),尽管对H2PO4具有交叉敏感性。为了提高性能,5和7嵌入到氟化物印迹的聚合物基质中,以提供固态传感器(5P和7P,分别)。图5P在水中显示出良好的灵敏度(360M-1)和特异性。此外,它具有低的检测极限(35µm)和响应线性范围(118-6300µm),涵盖了环境保护局设定的极限(211µm)。此外,5P还在实际样品测试中显示出良好的可重用性和足够的恢复值(102±2%),构成了低成本阴离子印迹聚合物探针的第一个示例,该探针专门用于选择性感测水性样品中的氟化物。
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 µm) below international guidelines, albeit with cross-sensitivity to H2PO4‾. 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 µm) and a response linear range (118-6300 µm) encompassing the limit established by the Environmental Protection Agency (211 µm). 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.