{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,9]],"date-time":"2026-03-09T03:55:56Z","timestamp":1773028556486,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,10,25]],"date-time":"2022-10-25T00:00:00Z","timestamp":1666656000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior","doi-asserted-by":"publisher","award":["UIDB\/50006\/2020"],"award-info":[{"award-number":["UIDB\/50006\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior","doi-asserted-by":"publisher","award":["UIDP\/50006\/2020"],"award-info":[{"award-number":["UIDP\/50006\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior","doi-asserted-by":"publisher","award":["PTDC\/QUI-QOR\/29426\/2017"],"award-info":[{"award-number":["PTDC\/QUI-QOR\/29426\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior","doi-asserted-by":"publisher","award":["PTDC\/QUI-QIN\/28142\/2017"],"award-info":[{"award-number":["PTDC\/QUI-QIN\/28142\/2017"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia and Minist\u00e9rio da Ci\u00eancia, Tecnologia e Ensino Superior","doi-asserted-by":"publisher","award":["EXPL\/QUI-OUT\/1554\/2021"],"award-info":[{"award-number":["EXPL\/QUI-OUT\/1554\/2021"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The search for accurate and sensitive methods to detect chemical substances, namely cations and anions, is urgent and widely sought due to the enormous impact that some of these chemical species have on human health and on the environment. Here, we present a new platform for the efficient sensing of Cu2+ and Li+ cations. For this purpose, two novel photoactive diketopyrrolopyrrole-rhodamine conjugates were synthesized through the condensation of a diketopyrrolopyrrole dicarbaldehyde with rhodamine B hydrazide. The resulting chemosensors 1 and 2, bearing one or two rhodamine hydrazide moieties, respectively, were characterized by 1H and 13C NMR and high-resolution mass spectrometry, and their photophysical and ion-responsive behaviours were investigated via absorption and fluorescence measurements. Chemosensors 1 and 2 displayed a rapid colorimetric response upon the addition of Cu2+, with a remarkable increase in the absorbance and fluorescence intensities. The addition of other metal ions caused no significant effects. Moreover, the resulting chemosensor-Cu2+ complexes revealed to be good probes for the sensing of Li+ with reversibility and low detection limits. The recognition ability of the new chemosensors was investigated by absorption and fluorescence titrations and competitive studies.<\/jats:p>","DOI":"10.3390\/molecules27217219","type":"journal-article","created":{"date-parts":[[2022,10,26]],"date-time":"2022-10-26T02:47:26Z","timestamp":1666752446000},"page":"7219","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Synthesis of Novel Diketopyrrolopyrrole-Rhodamine Conjugates and Their Ability for Sensing Cu2+ and Li+"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0485-8023","authenticated-orcid":false,"given":"Carla","family":"Queir\u00f3s","sequence":"first","affiliation":[{"name":"LAQV-REQUIMTE, Department of Chemistry and Biochemistry, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6019-4068","authenticated-orcid":false,"given":"V\u00edtor A. S.","family":"Almod\u00f4var","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal"}]},{"given":"F\u00e1bio","family":"Martins","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Department of Chemistry and Biochemistry, University of Porto, 4169-007 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1967-8853","authenticated-orcid":false,"given":"Andreia","family":"Leite","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Department of Chemistry and Biochemistry, University of Porto, 4169-007 Porto, 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\/0000-0003-0393-1655","authenticated-orcid":false,"given":"Ana M. G.","family":"Silva","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Department of Chemistry and Biochemistry, University of Porto, 4169-007 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1039\/C4CS00248B","article-title":"Diketopyrrolopyrrole: Brilliant red pigment dye-based fluorescent probes and their applications","volume":"44","author":"Kaur","year":"2015","journal-title":"Chem. Soc. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"280","DOI":"10.1002\/adom.201400559","article-title":"Diketopyrrolopyrroles: Synthesis, reactivity, and optical properties","volume":"3","author":"Grzybowski","year":"2015","journal-title":"Adv. Opt. Mater."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Auwalu, M.A., and Cheng, S. (2021). Diketopyrrolopyrrole fluorescent probes, photophysical and biological applications. 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