title: The Role of Ligand Topology in the Decomplexation of Luminescent Lanthanide Complexes by Dipicolinic Acid.
abstract: In this study, we present the aqueous solution behavior of two luminescent lanthanide antenna complexes (Eu3+⊂1, Dy3+⊂9) with different ligand topologies in the presence of dipicolinic acid (DPA, pyridine-2,6-dicarboxylic acid). Macrocyclic (1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid, DO3A, 9) and acyclic (1,4,7-triazaheptane-1,1,7,7-tetraacetic acid, DTTA, 1) ligands have been selected to form a ratiometric pair in which Dy3+⊂9 acts as a reference and Eu3+⊂1 acts as a probe for the recognition of DPA. The pair of luminescent complexes in water reveals the capability to work as a DPA luminescent sensor. The change of emission intensity of Eu3+indicates the occurrence of a new sensitization path for the lanthanide cation through excitation of DPA. NMR evidence implies the presence of free 1 and mass spectrometry shows the formation of emitting [EuDPA2]-as a result of a ligand exchange reaction.
authors.affiliation: Dipartimento di Scienze Chimiche Università di Padova and INSTM, Via F. Marzolo 1, 35131, Padova, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Mian
authors.affiliation: ICMATE-CNR and INSTM, Dipartimento di Scienze Chimiche Università di Padova, Via F. Marzolo 1, 35131, Padova, Italy. gregorio.bottaro@cnr.it.
authors.forename: Gregorio
authors.identifier: http://orcid.org/0000-0001-6196-8638
authors.initials: G
authors.lastname: Bottaro
authors.affiliation: ICMATE-CNR and INSTM, Dipartimento di Scienze Chimiche Università di Padova, Via F. Marzolo 1, 35131, Padova, Italy.
authors.forename: Roberta
authors.initials: R
authors.lastname: Seraglia
authors.affiliation: ISTM-CNR, Via C. Golgi 19, 20133, Milano, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Cavazzini
authors.affiliation: ISTM-CNR, Via C. Golgi 19, 20133, Milano, Italy. silvio.quici@istm.cnr.it.
authors.forename: Silvio
authors.initials: S
authors.lastname: Quici
authors.affiliation: Dipartimento di Scienze Chimiche Università di Padova and INSTM, Via F. Marzolo 1, 35131, Padova, Italy.|ICMATE-CNR and INSTM, Dipartimento di Scienze Chimiche Università di Padova, Via F. Marzolo 1, 35131, Padova, Italy.
authors.forename: Lidia
authors.initials: L
authors.lastname: Armelao
mesh_terms: D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D008024:Ligands; D049408:Luminescent Agents / Q000138:chemical synthesis / Q000737:chemistry*; D008163:Luminescent Measurements; D015394:Molecular Structure; D010848:Picolinic Acids / Q000737:chemistry*
chemical_list: D056831:Coordination Complexes; D028581:Lanthanoid Series Elements; D008024:Ligands; D049408:Luminescent Agents; D010848:Picolinic Acids; C004860:dipicolinic acid
keywords: decomplexation; dipicolinic acid; lanthanide complexes; luminescence; ratiometric sensor