Fluorescence lifetime-based sensing of sodium by an optode

Abstract

We report a 1,2,3-triazol fluoroionophore for detecting Na(+) that shows in vitro enhancement in the Na(+)-induced fluorescence intensity and decay time. The Na(+)-selective molecule 1 was incorporated into a hydrogel as a part of a fiber optical sensor. This sensor allows the direct determination of Na(+) in the range of 1-10 mM by measuring reversible fluorescence decay time changes.

Design of Na+‐Selective Fluorescent Probes: A Systematic Study of the Na+‐Complex Stability and the Na+/K+ Selectivity in Acetonitrile and Water

“…[8] The long-wavelength CT absorption for the diethylaminocoumarin derivatives 1-5 centered at around4 10 nm and for 8 and 9 at around 430 nm in CH 3 CN. [8] The long-wavelength CT absorption for the diethylaminocoumarin derivatives 1-5 centered at around4 10 nm and for 8 and 9 at around 430 nm in CH 3 CN.…”

“…The UV/Vis absorption spectra of fluoroionophores 1, 3, 4, 8 and 9 exhibit two charget ransfer (CT) bands in CH 3 CN (see Figures S1-S4, S6 and S7 in the Supporting Information), as already found for fluoroionophore 2. [8] The long-wavelength CT absorption for the diethylaminocoumarin derivatives 1-5 centered at around4 10 nm and for 8 and 9 at around 430 nm in CH 3 CN. The second CT absorption band, which is typical for pconjugated anilino-1,2,3-triazol-1,4-diyl-fluoroionophores,c an be found for 1-4, 8 and 9 at around 290 nm in CH 3 CN corresponding to aC Tf rom the nitrogen lone pair of the aromatic ring (donor) to the 1,2,3-triazolea cceptor unit.…”

“…[7a] Furthermore, we attached different alkoxy groups in the ortho-position of the aniline unit to enhance the K + complex stability andt he K + /Na + selectivity. [8] Fluorescent probe 2 showed ah igh Na + /K + selectivity when embedded in ap olymethacrylate hydrogel and am oderate Na + /K + selectivity under simulated physiological conditions. [8] Fluorescent probe 2 showed ah igh Na + /K + selectivity when embedded in ap olymethacrylate hydrogel and am oderate Na + /K + selectivity under simulated physiological conditions.…”

“…[7b-d] In addition, we successfully transferredt he signal transduction chain to an exclusive Na + sensing by introductiono faN-(o-methoxyphenyl)aza-15-crown-5 ionophore, as shown in fluoroionophore 2 (Scheme 1). [8] Fluorescent probe 2 showed ah igh Na + /K + selectivity when embedded in ap olymethacrylate hydrogel and am oderate Na + /K + selectivity under simulated physiological conditions. [8] In that case, we reached ab etter Na + /K + selectivity and ah igher Na + -induced fluorescence enhancement( FE), when the aniline donor is connected to the position 4o ft he triazole and the coumarin acceptort ot he position 1, as shown in fluorescentp robe 2 (cf.…”

1,2,3‐Triazol‐1,4‐diyl‐Fluoroionophores for Zn2+, Mg2+ and Ca2+ based on Fluorescence Intensity Enhancements in Water

“…The exchange of the aza‐18‐crown‐6 by an aza‐15‐crown‐5 unit (cf. Na1) reduces the cavity of the macrocycle and enables the selective extracellular Na + level detection [12b] . After addition of K + or Na + the PET is interrupted and a fluorescence intensity enhancement (FE) is observed.…”