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NMR spectrometers are part of Rede Nacional de RMN (PTNMR), supported by FCT-MCTES","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}]},{"name":"The NMR spectrometers are part of Rede Nacional de RMN (PTNMR), supported by FCT-MCTES","award":["UIDP\/50006\/2020"],"award-info":[{"award-number":["UIDP\/50006\/2020"]}]},{"name":"The NMR spectrometers are part of Rede Nacional de RMN (PTNMR), supported by FCT-MCTES","award":["UI\/BD\/153617\/2022"],"award-info":[{"award-number":["UI\/BD\/153617\/2022"]}]},{"name":"The NMR spectrometers are part of Rede Nacional de RMN (PTNMR), supported by FCT-MCTES","award":["RECI\/BBB-BEP\/0124\/2012"],"award-info":[{"award-number":["RECI\/BBB-BEP\/0124\/2012"]}]},{"name":"The NMR spectrometers are part of Rede Nacional de RMN (PTNMR), supported by FCT-MCTES","award":["ROTEIRO\/0031\/2013\u2014PINFRA\/22161\/2016"],"award-info":[{"award-number":["ROTEIRO\/0031\/2013\u2014PINFRA\/22161\/2016"]}]},{"name":"FEDER through 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several coumarin-3-carboxamides with different azacrown ether moieties were designed and tested as potential luminescent sensors for metal ions. The derivative containing a 1-aza-15-crown-5 as a metal chelating group was found to yield the strongest response for Ca2+ and Pb2+, exhibiting an eight- and nine-fold emission increase, respectively, while other cations induced no changes in the optical properties of the chemosensor molecule. Job\u2019s plots revealed a 1:1 binding stoichiometry, with association constants of 4.8 \u00d7 104 and 8.7 \u00d7 104 M\u20131, and limits of detection of 1.21 and 8.04 \u00b5M, for Ca2+ and Pb2+, respectively. Computational studies suggest the existence of a PET quenching mechanism, which is inhibited after complexation with each of these two metals. Proton NMR experiments and X-ray crystallography suggest a contribution from the carbonyl groups in the coumarin-3-carboxamide fluorophore in the coordination sphere of the metal ion.<\/jats:p>","DOI":"10.3390\/molecules29020527","type":"journal-article","created":{"date-parts":[[2024,1,22]],"date-time":"2024-01-22T11:36:41Z","timestamp":1705923401000},"page":"527","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Development of Fluorescent Chemosensors for Calcium and Lead Detection"],"prefix":"10.3390","volume":"29","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4810-2770","authenticated-orcid":false,"given":"Liliana J.","family":"Gomes","sequence":"first","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1940-8703","authenticated-orcid":false,"given":"Mani","family":"Outis","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3672-0045","authenticated-orcid":false,"given":"Clara S. B.","family":"Gomes","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4331-714X","authenticated-orcid":false,"given":"Augusto C.","family":"Tom\u00e9","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3285-4919","authenticated-orcid":false,"given":"Artur J.","family":"Moro","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Departamento de Qu\u00edmica, Faculdade de Ci\u00eancias e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"7105","DOI":"10.1039\/C7CS00240H","article-title":"Fluorescent Chemosensors: The Past, Present and Future","volume":"46","author":"Wu","year":"2017","journal-title":"Chem. 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