{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T06:51:24Z","timestamp":1772261484613,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,3,13]],"date-time":"2025-03-13T00:00:00Z","timestamp":1741824000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT)","award":["IDB\/00100\/2020"],"award-info":[{"award-number":["IDB\/00100\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT)","award":["UIDP\/00100\/2020"],"award-info":[{"award-number":["UIDP\/00100\/2020"]}]},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia (FCT)","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]},{"name":"DCRRNI ID Concurso de avalia\u00e7\u00e3o no \u00e2mbito do Programa Plurianual de Financiamento de Unidades de I&amp;D (2017\/2018)\u2014Financiamento Base","award":["IDB\/00100\/2020"],"award-info":[{"award-number":["IDB\/00100\/2020"]}]},{"name":"DCRRNI ID Concurso de avalia\u00e7\u00e3o no \u00e2mbito do Programa Plurianual de Financiamento de Unidades de I&amp;D (2017\/2018)\u2014Financiamento Base","award":["UIDP\/00100\/2020"],"award-info":[{"award-number":["UIDP\/00100\/2020"]}]},{"name":"DCRRNI ID Concurso de avalia\u00e7\u00e3o no \u00e2mbito do Programa Plurianual de Financiamento de Unidades de I&amp;D (2017\/2018)\u2014Financiamento Base","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]},{"name":"DCRRNI ID Concurso de avalia\u00e7\u00e3o no \u00e2mbito do Programa Plurianual de Financiamento de Unidades de I&amp;D (2017\/2018)\u2014Financiamento Program\u00e1tico","award":["IDB\/00100\/2020"],"award-info":[{"award-number":["IDB\/00100\/2020"]}]},{"name":"DCRRNI ID Concurso de avalia\u00e7\u00e3o no \u00e2mbito do Programa Plurianual de Financiamento de Unidades de I&amp;D (2017\/2018)\u2014Financiamento Program\u00e1tico","award":["UIDP\/00100\/2020"],"award-info":[{"award-number":["UIDP\/00100\/2020"]}]},{"name":"DCRRNI ID Concurso de avalia\u00e7\u00e3o no \u00e2mbito do Programa Plurianual de Financiamento de Unidades de I&amp;D (2017\/2018)\u2014Financiamento Program\u00e1tico","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]},{"name":"FCT","award":["IDB\/00100\/2020"],"award-info":[{"award-number":["IDB\/00100\/2020"]}]},{"name":"FCT","award":["UIDP\/00100\/2020"],"award-info":[{"award-number":["UIDP\/00100\/2020"]}]},{"name":"FCT","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]},{"name":"DCRRNI ID Concurso para Atribui\u00e7\u00e3o do Estatuto e Financiamento de Laborat\u00f3rios Associados","award":["IDB\/00100\/2020"],"award-info":[{"award-number":["IDB\/00100\/2020"]}]},{"name":"DCRRNI ID Concurso para Atribui\u00e7\u00e3o do Estatuto e Financiamento de Laborat\u00f3rios Associados","award":["UIDP\/00100\/2020"],"award-info":[{"award-number":["UIDP\/00100\/2020"]}]},{"name":"DCRRNI ID Concurso para Atribui\u00e7\u00e3o do Estatuto e Financiamento de Laborat\u00f3rios Associados","award":["LA\/P\/0056\/2020"],"award-info":[{"award-number":["LA\/P\/0056\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The development of gadolinium-based magnetic resonance imaging (MRI) contrast agents (CAs) is a highly challenging and demanding research field in metal-coordination medicinal chemistry. The recognized high capacity of hydroxypyridinone (HOPO)-based compounds to coordinate Gd (III) led us to evaluate the set of physic\u2013chemical\u2013biological properties of a new Gd (III) complex with a hexadentate tripodal ligand (H3L) containing three 3,4-HOPO chelating moieties attached to an anchoring cyclohexane backbone. In particular, the thermodynamic stability constants of the complex were evaluated by potentiometry, showing the formation of a highly stable (1:1) Gd-L complex (log \u03b2GdL = 26.59), with full coordination even in an acid-neutral pH under the experimental conditions used. Molecular simulations of the Gd (III) complex revealed a minimum energy structure with somewhat-distorted octahedral geometry, involving full metal hexa-coordination by the three bidentate moieties of the ligand arms, indicating that an extra water molecule should be coordinated to the metal ion, an important feature for the CAs (and the required enhancement of water proton relaxivity). In vivo biodistribution studies with the 67Ga complex, as a surrogate of the corresponding Gd complex, showed in vivo stability and rapid excretion from the animal body. Though deserving further investigation, these results may give an input on future perspectives towards new MRI diagnostic agents.<\/jats:p>","DOI":"10.3390\/molecules30061295","type":"journal-article","created":{"date-parts":[[2025,3,13]],"date-time":"2025-03-13T10:16:45Z","timestamp":1741861005000},"page":"1295","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Gadolinium Complex with Tris-Hydroxypyridinone as an Input for New Imaging Probes: Thermodynamic Stability, Molecular Modeling and Biodistribution"],"prefix":"10.3390","volume":"30","author":[{"given":"In\u00eas","family":"Dias","sequence":"first","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Institute of Molecular Sciences, Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7186-2060","authenticated-orcid":false,"given":"Lurdes","family":"Gano","sequence":"additional","affiliation":[{"name":"Centro de Ci\u00eancias e Tecnologias Nucleares, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Estrada Nacional 10 (km 139,7), Loures, 2695-066 Bobadela, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8554-4992","authenticated-orcid":false,"given":"S\u00edlvia","family":"Chaves","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Institute of Molecular Sciences, Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4069-9368","authenticated-orcid":false,"given":"M. Am\u00e9lia","family":"Santos","sequence":"additional","affiliation":[{"name":"Centro de Qu\u00edmica Estrutural, Institute of Molecular Sciences, Departamento de Engenharia Qu\u00edmica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"957","DOI":"10.1021\/acs.chemrev.8b00363","article-title":"Chemistry of MRI contrast agents: Current challenges and new frontiers","volume":"119","author":"Wahsner","year":"2019","journal-title":"Chem. Rev."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1562","DOI":"10.1016\/j.ccr.2006.03.015","article-title":"High sensitivity lanthanide(III) based probes for MR-medical imaging","volume":"250","author":"Aime","year":"2006","journal-title":"Coord. Chem. 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