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DOE OSTI · 2345191

Aqueous phosphate detection using Eu(acac) 3

Anderson, Benjamin R.·Gese, Natalie·Nawani, Pranav·Eilers, Hergen
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Abstract

Currently, the majority of phosphate-sensitive phosphors reported in literature are metal-based complexes that require complicated and expensive synthesis to prepare. Here, in this study, we investigate the phosphate detecting capabilities of an inexpensive off-the-shelf phosphor: Eu(acac) 3 . We characterize its phosphate sensitivity as a function of sensor concentration and find that the quenching coefficient is inversely proportional to sensor concentration. This results in the limit-of-detection scaling linearly with sensor concentration. We determine its concentration-independent sensitivity to be 1.558 ± 0.012, which results in our lowest sensor concentration (44 μM) having a limit-of-detection of 3.39 ± 0.68 μM. We also find that for phosphate concentrations less than the sensor concentration, the fluorescence intensity ratio behaves linearly, but transitions to a non-linear functionality as the phosphate concentration exceeds the sensor concentration.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS

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Anderson, Benjamin R., Gese, Natalie, Nawani, Pranav, Eilers, Hergen. 2023-11-11. Aqueous phosphate detection using Eu(acac) 3. https://doi.org/10.1007/s00340-023-08134-4

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