Iridium-Based Time-Resolved Luminescent Sensor for Ba<sup>2+</sup> Detection
We present a new time-resolved chemosensor for the detection of Ba<sup>2+</sup> ions. Our sensor is based on an iridium(III) compound with dual (fluorescent and phosphorescent) emission. The nature of the luminescence response of the sensor depends on its state; specifically, the phosphorescence emission of the free state at long wavelengths is strongly suppressed, while that of the Ba<sup>2+</sup>-chelated compound is strongly enhanced. Furthermore, the residual phosphorescence emission of the free compound decays with two short decay constants, τ<sub>free</sub><sup>1</sup> ∼ 3.5 ns (88%) and τ<sub>free</sub><sup>2</sup> ∼ 209 ns (12%), while the chelated compound decays with two long decay constants, τ<sub>bound</sub><sup>1</sup> ∼ 429 ns (21%) and τ<sub>bound</sub><sup>2</sup> ∼ 1128 ns (76%). This exceptional behavior, supported by quantum chemical calculations, allows a time-based separation between the signals of the free and the chelated species. Among other applications, our sensor could be the basis of a Ba<sup>2+</sup> tagging detector for neutrinoless double beta decay searches in xenon.
Authors
- Zoraida Freixa (ORCID: https://orcid.org/0000-0002-2044-2725)
- Claire Tonnelé (ORCID: https://orcid.org/0000-0003-0791-8239)
- Fernando P. Cossío (ORCID: https://orcid.org/0000-0002-4526-2122)
- Celia Rogero (ORCID: https://orcid.org/0000-0002-2812-8853)
- A. I. Aranburu (ORCID: https://orcid.org/0000-0002-0373-4662)
- Ariadna Pazos (ORCID: https://orcid.org/0000-0002-6074-6213)
- F. Monrabal (ORCID: https://orcid.org/0000-0002-4047-5620)
- J.J. Gómez-Cadenas (ORCID: https://orcid.org/0000-0002-8224-7714)
- P. Herrero-Gómez (ORCID: https://orcid.org/0000-0002-1517-7779)
- Jose Eduardo Barcelon (ORCID: https://orcid.org/0000-0001-8277-0073)
- Gabriel Molina‐Terriza (ORCID: https://orcid.org/0000-0002-7905-4938)
- A. Brodolin
- P. R. G. Valle
- Mikel Elorza (ORCID: https://orcid.org/0009-0000-4219-6193)
Institutions
- Ikerbasque (ES)
- University of the Basque Country (ES)
- Hebrew University of Jerusalem (IL)
- FZU ‒ Institute of Physics of the Academy of Sciences of the Czech Republic (CZ)
- Material Physics Center (ES)
- Donostia International Physics Center (ES)
Publication Details
- Journal
- ACS Sensors
- Published
- 2025-04-11
- DOI
- https://doi.org/10.1021/acssensors.4c01892
- Citations
- 2
- Primary Topic
- Advanced biosensing and bioanalysis techniques
- Type
- article
- Field-Weighted Citation Impact
- 1.61
Funders
- U.S. Department of Energy
- Welch Foundation
- “la Caixa” Foundation
- Hezkuntza, Hizkuntza Politika Eta Kultura Saila, Eusko Jaurlaritza
- Eusko Jaurlaritza
- Generalitat Valenciana
- Euskal Herriko Unibertsitatea
- Israel Science Foundation
- PAZY Foundation
- Horizon 2020 Framework Programme
- European Research Council
- Fundação para a Ciência e a Tecnologia
- European Regional Development Fund
- Agencia Estatal de Investigación
- Division of Chemistry