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Svítok A, Blahut J, Urbanovský P, Hermann P. Dynamics of Coordinated Phosphonate Group Directly Observed by 17O-NMR in Lanthanide(iii) Complexes of a Mono(ethyl phosphonate) DOTA Analogue. Chemistry 2024; 30:e202400970. [PMID: 38624256 DOI: 10.1002/chem.202400970] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/17/2024]
Abstract
Biological phosphates can coordinate metal ions and their complexes are common in living systems. Dynamics of mutual oxygen atom exchange in the tetrahedral group in complexes has not been investigated. Here, we present a direct experimental proof of exchange ("phosphonate rotation") in model Ln(III) complexes of monophosphonate H4dota analogue which alters phosphorus atom chirality of coordinated phosphonate monoester. Combination of macrocycle-based isomerism with P-based chirality leads to several diastereoisomers. (Non)-coordinated oxygen atoms were distinguished through 17O-labelled phosphonate group and their mutual exchange was followed by various NMR techniques and DFT calculations. The process is sterically demanding and occurs through bulky bidentate (κ2-PO2)- coordination and was observed only in twisted-square antiprism (TSA) diastereoisomer of large Ln(III) ions. Its energy demands increase for smaller Ln(III) ions (298ΔG≠(exp./DFT)=51.8/52.1 and 61.0/71.5 kJ mol-1 for La(III) and Eu(III), respectively). These results are helpful in design of such complexes as MRI CA and for protein paramagnetic NMR probes. It demonstrates usefulness of 17O NMR to study solution dynamics in complexes involving phosphorus acid derivatives and it may inspire use of this method to study dynamics of phosphoric acid derivatives (as e. g. phosphorus acid-based inhibitors of metalloenzymes) in different areas of chemistry.
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Affiliation(s)
- Adam Svítok
- Department Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 12843, Prague 2, Czech Republic
| | - Jan Blahut
- Institute of Organic Chemistry and Biochemistry, Czech Academy of Science, Flemingovo náměstí 2, 16000, Prague 6, Czech Republic
| | - Peter Urbanovský
- Department Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 12843, Prague 2, Czech Republic
| | - Petr Hermann
- Department Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 2030, 12843, Prague 2, Czech Republic
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El-Baz N, Nunn BM, Bates PJ, O’Toole MG. The Impact of PEGylation on Cellular Uptake and In Vivo Biodistribution of Gold Nanoparticle MRI Contrast Agents. BIOENGINEERING (BASEL, SWITZERLAND) 2022; 9:bioengineering9120766. [PMID: 36550972 PMCID: PMC9774698 DOI: 10.3390/bioengineering9120766] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Revised: 11/23/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022]
Abstract
Gold nanoparticles (GNPs) have immense potential in biomedicine, but understanding their interactions with serum proteins is crucial as it could change their biological profile due to the formation of a protein corona, which could then affect their ultimate biodistribution in the body. Grafting GNPs with polyethylene glycol (PEG) is a widely used practice in research in order to decrease opsonization of the particles by serum proteins and to decrease particle uptake by the mononuclear phagocyte system. We investigated the impact of PEGylation on the formation of protein coronae and the subsequent uptake by macrophages and MDA-MB-231 cancer cells. Furthermore, we investigated the in vivo biodistribution in xenograft tumor-bearing mice using a library of 4 and 10 nm GNPs conjugated with a gadolinium chelate as MRI contrast agent, cancer-targeting aptamer AS1411 (or CRO control oligonucleotide), and with or without PEG molecules of different molecular weight (Mw: 1, 2, and 5 kDa). In vitro results showed that PEG failed to decrease the adsorption of proteins; moreover, the cellular uptake by macrophage cells was contingent on the different configurations of the aptamers and the length of the PEG chain. In vivo biodistribution studies showed that PEG increased the uptake by tumor cells for some GNPs, albeit it did not decrease the uptake of GNPs by macrophage-rich organs.
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Affiliation(s)
- Nagwa El-Baz
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40292, USA
| | - Betty M. Nunn
- Department of Bioengineering, University of Louisville, Louisville, KY 40292, USA
| | - Paula J. Bates
- Department of Medicine, University of Louisville, Louisville, KY 40202, USA
| | - Martin G. O’Toole
- Department of Bioengineering, University of Louisville, Louisville, KY 40292, USA
- Correspondence:
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3
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Wang G, Martin H, Amézqueta S, Ràfols C, Bonnet CS, Angelovski G. Insights into the Responding Modes of Highly Potent Gadolinium-Based Magnetic Resonance Imaging Probes Sensitive to Zinc Ions. Inorg Chem 2022; 61:16256-16265. [PMID: 36007145 DOI: 10.1021/acs.inorgchem.2c01960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Zn ions (Zn2+) play an important biological role in many diseases; hence, an imaging method for monitoring the Zn2+ distribution in tissues could provide important clinical insights. Recently, we reported a potent Zn-sensitive probe based on the Gd-DO3A (DO3A = 1,4,7,10-tetraazacyclododecane-1,4,7-tricarboxylic acid), modified tyrosine. and di(2-picolyl)amine chelator for this metal cation, which generates an outstanding magnetic resonance imaging (MRI) response. Here we further explored the origin of this unprecedented response and expanded the choice of potential MRI probes by preparing the free acid version of the initial MRI sensor. We report a detailed investigation of the 1H NMR dispersion, 17O NMR, and isothermal titration calorimetry properties of these two MRI probes upon interaction with Zn2+. The performed experiments confirm selective interaction of the MRI probes and target metal cation, which causes substantial changes in the coordination sphere of the paramagnetic center. It also evidenced some aggregation, which enhances the relaxivity response. Interestingly, conversion of the methyl ester to the free carboxylic acid of the tyrosine moiety changes the nature of the aggregates and leads to a smaller relaxivity response. The probes interact with human serum albumin (HSA) in the absence of Zn2+, which leads to a possible modification of the coordination sphere of Gd3+ or a substantial change in the exchange rate of second-sphere water molecules. In the presence of Zn2+, the interaction with HSA is very weak, demonstrating the importance of the Zn2+ coordination sphere in the behavior of these systems.
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Affiliation(s)
- Gaoji Wang
- MR Neuroimaging Agents, Max Planck Institute for Biological Cybernetics, Tuebingen 72076, Germany.,School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, P. R. China
| | - Harlei Martin
- Centre de Biophysique Moléculaire, UPR 4301, CNRS, Université d'Orléans, rue Charles Sadron, Orléans 45071, France
| | - Susana Amézqueta
- Departament d'Enginyeria Química i Química Analítica, Facultat de Química, Universitat de Barcelona, c/Martí i Franquès, 1, Barcelona 08028, Spain.,Institut de Biomedicina, Universitat de Barcelona, Barcelona 08028, Spain
| | - Clara Ràfols
- Departament d'Enginyeria Química i Química Analítica, Facultat de Química, Universitat de Barcelona, c/Martí i Franquès, 1, Barcelona 08028, Spain.,Institut de Biomedicina, Universitat de Barcelona, Barcelona 08028, Spain
| | - Célia S Bonnet
- Centre de Biophysique Moléculaire, UPR 4301, CNRS, Université d'Orléans, rue Charles Sadron, Orléans 45071, France
| | - Goran Angelovski
- MR Neuroimaging Agents, Max Planck Institute for Biological Cybernetics, Tuebingen 72076, Germany.,Laboratory of Molecular and Cellular Neuroimaging, International Center for Primate Brain Research, Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 20031, P. R. China
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Holzapfel M, Baldau T, Kerpa S, Guadalupi G, Qi B, Liu Y, Parak WJ, Maison W. Solution Structure and Relaxivity of Ln‐DOTXAZA Derivatives. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Malte Holzapfel
- Fraunhofer Institute for Applied Polymer Research: Fraunhofer-Institut fur Angewandte Polymerforschung IAP Center for Applied Nanoscience GERMANY
| | - Torben Baldau
- Universität Hamburg: Universitat Hamburg Department of Chemistry GERMANY
| | - Svenja Kerpa
- Universität Hamburg: Universitat Hamburg Department of Chemistry GERMANY
| | | | - Bing Qi
- Universität Hamburg: Universitat Hamburg Center for Hybrid Nanostructure GERMANY
| | - Yang Liu
- Universität Hamburg: Universitat Hamburg Center for Hybrid Nanostructure GERMANY
| | - Wolfgang J. Parak
- Universität Hamburg: Universitat Hamburg Center for Hybrid Nanostructure GERMANY
| | - Wolfgang Maison
- University of Hamburg Chemistry Bundesstr. 45 20146 Hamburg GERMANY
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How the catalysis of the prototropic exchange affects the properties of lanthanide(III) complexes in their applications as MRI contrast agents. Inorganica Chim Acta 2022. [DOI: 10.1016/j.ica.2021.120730] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Zapolotsky EN, Qu Y, Babailov SP. Lanthanide complexes with polyaminopolycarboxylates as prospective NMR/MRI diagnostic probes: peculiarities of molecular structure, dynamics and paramagnetic properties. J INCL PHENOM MACRO 2021; 102:1-33. [PMID: 34785985 PMCID: PMC8582344 DOI: 10.1007/s10847-021-01112-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 10/05/2021] [Indexed: 11/29/2022]
Abstract
The paramagnetic lanthanide complexes with polyaminopolycarboxylate (PAPC) ligands attract considerable attention from the standpoint of potential applications thereof as relaxation agents used in medical magnetic resonance imaging (MRI) and in luminescent materials, as well as owing to promising use thereof as paramagnetic labels for studying the properties of biopolymers since they exhibit thermodynamic stability, good solubility in aqueous media and moderate toxicity. For the last decades, the NMR methods have been used to determine the physical and chemical properties of paramagnetic Ln compounds. The studies concerning paramagnetic NMR lanthanide-induced shifts (LISs) in dissolved Ln complexes, as well as the analysis of band shape as a function of temperature make it possible to obtain valuable information on the structure, intra- and intermolecular dynamics and paramagnetic properties thereof. This review is devoted solely to the following features: firstly, the processes of intramolecular dynamics of lanthanide complexes with polyamino-polycarboxylate ligands such as DOTA, EDTA and DTPA and their derivatives studied by NMR; secondly, the LISs of lanthanide complexes with EDTA, DOTA, DTPA and some of their derivatives depending on temperature and pH. Moreover, in this review, for the first time, the dependence of the activation energy of molecular dynamics in complexes with polydentate ligands on the atomic number of the lanthanide cation is analyzed and a monotonic change in energy is detected, which is due to the effect of lanthanide contraction. It should be noted that this phenomenon is quite general and may also appear in the future in many other series of lanthanide complexes with both other multidentate ligands and with bidentate and monodentate ligands. In the future, it is possible to predict the dependence of the properties of certain lanthanide complexes on the ionic radius of the lanthanide cation based on the approaches presented in the review. In this review, we have also presented the dynamic NMR as the main research method widely used to analyze the processes of molecular dynamics, and the structural studies based on the NMR relaxation spectroscopy and LIS analysis.
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Affiliation(s)
- Eugeny N. Zapolotsky
- A.V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Av. Lavrentyev 3, Novosibirsk, Russia 630090
| | - Yanyang Qu
- Institute of Chemical Materials, CAEP, P. O. Box 919-311, Mianyang, 621900 Sichun China
| | - Sergey P. Babailov
- A.V. Nikolaev Institute of Inorganic Chemistry, Siberian Branch of the Russian Academy of Sciences, Av. Lavrentyev 3, Novosibirsk, Russia 630090
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Laine S, Morfin JF, Galibert M, Aucagne V, Bonnet CS, Tóth É. Lanthanide DO3A-Complexes Bearing Peptide Substrates: The Effect of Peptidic Side Chains on Metal Coordination and Relaxivity. Molecules 2021; 26:2176. [PMID: 33918899 PMCID: PMC8069257 DOI: 10.3390/molecules26082176] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/02/2021] [Accepted: 04/07/2021] [Indexed: 12/22/2022] Open
Abstract
Two DO3A-type ligands conjugated to substrates of urokinase (L3) and caspase-3 (L4) via a propyl-amide linker were synthesized and their lanthanide(III) (Ln3+) complexes studied. A model compound without peptide substrate (L2) and an amine derivative ligand mimicking the state after enzymatic cleavage (L1) were also prepared. Proton Nuclear Magnetic Relaxation Dispersion (NMRD) profiles recorded on the gadolinium(III) (Gd3+) complexes, complemented with the assessment of hydration numbers via luminescence lifetime measurements on the Eu3+ analogues, allowed us to characterize the lanthanide coordination sphere in the chelates. These data suggest that the potential donor groups of the peptide side chains (carboxylate, amine) interfere in metal coordination, leading to non-hydrated LnL3 and LnL4 complexes. Nevertheless, GdL3 and GdL4 retain a relatively high relaxivity due to an important second-sphere contribution generated by the strongly hydrophilic peptide chain. Weak PARACEST effects are detected for the amine-derivative EuL1 and NdL1 chelates. Unfortunately, the GdL3 and GdL4 complexes are not significantly converted by the enzymes. The lack of enzymatic recognition of these complexes can likely be explained by the participation of donor groups from the peptide side chain in metal coordination.
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Affiliation(s)
| | | | | | | | | | - Éva Tóth
- Centre de Biophysique Moléculaire, CNRS UPR 4301, Rue Charles Sadron, CEDEX 2, 45071 Orléans, France; (S.L.); (J.-F.M.); (M.G.); (V.A.); (C.S.B.)
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Urbanovský P, Kotek J, Císařová I, Hermann P. Selective and clean synthesis of aminoalkyl- H-phosphinic acids from hypophosphorous acid by phospha-Mannich reaction. RSC Adv 2020; 10:21329-21349. [PMID: 35518776 PMCID: PMC9059144 DOI: 10.1039/d0ra03075a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 05/15/2020] [Indexed: 12/25/2022] Open
Abstract
Aminoalkyl-H-phosphinic acids, also called aminoalkylphosphonous acids, are investigated as biologically active analogues of carboxylic amino acids and/or as valuable intermediates for synthesis of other aminoalkylphosphorus acids. Their synthesis has been mostly accomplished by phospha-Mannich reaction of a P–H precursor, an aldehyde and an amine. The reaction is rarely clean and high-yielding. Here, reaction of H3PO2 with secondary amines and formaldehyde in wet AcOH led to aminomethyl-H-phosphinic acids in nearly quantitative yields and with almost no by-products. Surprisingly, the reaction outcome depended on the basicity of the amines. Amines with pKa > 7–8 gave the desired products. For less basic amines, reductive N-methylation coupled with oxidation of H3PO2 to H3PO3 became a relevant side reaction. Primary amines reacted less clearly and amino-bis(methyl-H-phosphinic acids) were obtained only for very basic amines. Reaction yields with higher aldehydes were lower. Unique carboxylic–phosphinic–phosphonic acids as well as poly(H-phosphinic acids) derived from polyamines were obtained. Synthetic usefulness of the aminoalkyl-H-phosphinic was illustrated in P–H bond oxidation and its addition to double bonds, and in selective amine deprotection. Compounds with an ethylene-diamine fragment, e.g. most common polyazamacrocycles, are not suitable substrates. The X-ray solid-state structures of seventeen aminoalkyl-phosphinic acids were determined. In the reaction mechanism, N-hydroxyalkyl species R2NCH2OH and [R2N(CH2OH)2]+, probably stabilized as acetate esters, are suggested as the reactive intermediates. This mechanism is an alternative one to the known phospha-Mannich reaction mechanisms. The conditions can be utilized in syntheses of various aminoalkylphosphorus compounds. Acetic acid was used as a new solvent for phospha-Mannich reaction leading to clear reaction mixtures and high yields of the aminoalkylphosphonous acids (AHPA), and hydroxymethylated species were suggested as key intermediates in the reaction.![]()
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Affiliation(s)
- Peter Urbanovský
- Department of Inorganic Chemistry, Faculty of Science, Universita Karlova (Charles University) Hlavova 8/2030, 12843 Prague 2 Czech Republic +420-22195-1253 +420-22195-1263
| | - Jan Kotek
- Department of Inorganic Chemistry, Faculty of Science, Universita Karlova (Charles University) Hlavova 8/2030, 12843 Prague 2 Czech Republic +420-22195-1253 +420-22195-1263
| | - Ivana Císařová
- Department of Inorganic Chemistry, Faculty of Science, Universita Karlova (Charles University) Hlavova 8/2030, 12843 Prague 2 Czech Republic +420-22195-1253 +420-22195-1263
| | - Petr Hermann
- Department of Inorganic Chemistry, Faculty of Science, Universita Karlova (Charles University) Hlavova 8/2030, 12843 Prague 2 Czech Republic +420-22195-1253 +420-22195-1263
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Urbanovský P, Kotek J, Císařová I, Hermann P. The solid-state structures and ligand cavity evaluation of lanthanide(iii) complexes of a DOTA analogue with a (dibenzylamino)methylphosphinate pendant arm. Dalton Trans 2020; 49:1555-1569. [PMID: 31932828 DOI: 10.1039/c9dt04056k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A series of lanthanide(iii) complexes of a monophosphinate analogue of H4dota, 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic-10-methyl[(N,N-dibenzylamino)methyl]phosphinic acid (H4do3apDBAm = H4L1), were prepared and their solid-state structures were studied using single-crystal X-ray diffraction. In all structures, the ligand anion was octadentately coordinated to the Ln(iii) or Sc(iii) ions similarly to other DOTA-like ligands, i.e. forming parallel N4- and O4-planes. The lighter lanthanide(iii) complexes (till dysprosium) were nonacoordinated in the twisted square-antiprismatic (TSA) configuration with the apical coordination of water molecules or oxygen atoms from the neighbouring complex unit. The heavier lanthanide(iii) complexes (from terbium) were found as the "anhydrous" octacoordinated twisted square-antiprismatic (TSA') isomer. For the terbium(iii) ion, both forms were structurally characterized. The structural data of the Ln(iii)-H4L1 complexes and complexes of several related DOTA-like ligands were analysed. It clearly showed that the structural parameters for the square-antiprismatic (SA) isomers were clustered in a small range while those for the TSA/TSA' isomers were significantly more spread. The analysis also gave useful information about the influence of various pendant arms on the structure of the complexes of the DOTA-like ligands. The twist angle (torsion) of the chelate ring containing a larger phosphorus atom was similar to those of the remaining three acetate pendants. It led to a larger separation of the N4O4 planes and to smaller trans-O-Ln-O angles than the parameters found in the complexes of H4dota and its tetraamide derivatives dotam(R). It resulted in a relatively long bond between the metal ion and the coordinated water molecule. It led, together with the negative charge of the oxygen atoms forming the O4-plane, to an extremely fast water exchange rate reported for the Gd(iii)-H4L1 complex and, generally, to a fast water exchange of Gd(iii) complexes with the monophosphorus acid analogues of H4dota, H5do3ap/H4do3apR.
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Affiliation(s)
- Peter Urbanovský
- Universita Karlova (Charles University), Department of Inorganic Chemistry, Hlavova 2030, 128 43 Prague 2, Czech Republic.
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Bárta J, Hermann P, Kotek J. Coordination Behavior of 1,4-Disubstituted Cyclen Endowed with Phosphonate, Phosphonate Monoethylester, and H-Phosphinate Pendant Arms. Molecules 2019; 24:E3324. [PMID: 31547345 PMCID: PMC6767212 DOI: 10.3390/molecules24183324] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 09/06/2019] [Accepted: 09/08/2019] [Indexed: 11/17/2022] Open
Abstract
Three 1,4,7,10-tetraazacyclododecane-based ligands disubstituted in 1,4-positions with phosphonic acid, phosphonate monoethyl-ester, and H-phosphinic acid pendant arms, 1,4-H4do2p, 1,4-H2do2pOEt, and 1,4-H2Bn2do2pH, were synthesized and their coordination to selected metal ions, Mg(II), Ca(II), Mn(II), Zn(II), Cu(II), Eu(III), Gd(III), and Tb(III), was investigated. The solid-state structure of the phosphonate ligand, 1,4-H4do2p, was determined by single-crystal X-ray diffraction. Protonation constants of the ligands and stability constants of their complexes were obtained by potentiometry, and their values are comparable to those of previously studied analogous 1,7-disubstitued cyclen derivatives. The Gd(III) complex of 1,4-H4do2p is ~1 order of magnitude more stable than the Gd(III) complex of the 1,7-analogue, probably due to the disubstituted ethylenediamine-like structural motif in 1,4-H4do2p enabling more efficient wrapping of the metal ion. Stability of Gd(III)-1,4-H2do2pOEt and Gd(III)-H2Bn2do2pH complexes is low and the constants cannot be determined due to precipitation of the metal hydroxide. Protonations of the Cu(II), Zn(II), and Gd(III) complexes probably takes place on the coordinated phosphonate groups. Complexes of Mn(II) and alkali-earth metal ions are significantly less stable and are not formed in acidic solutions. Potential presence of water molecule(s) in the coordination spheres of the Mn(II) and Ln(III) complexes was studied by variable-temperature NMR experiments. The Mn(II) complexes of the ligands are not hydrated. The Gd(III)-1,4-H4do2p complex undergoes hydration equilibrium between mono- and bis-hydrated species. Presence of two-species equilibrium was confirmed by UV-Vis spectroscopy of the Eu(III)-1,4-H4do2p complex and hydration states were also determined by luminescence measurements of the Eu(III)/Tb(III)-1,4-H4do2p complexes.
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Affiliation(s)
- Jiří Bárta
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague 2, Czech Republic.
| | - Petr Hermann
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague 2, Czech Republic.
| | - Jan Kotek
- Department of Inorganic Chemistry, Faculty of Science, Charles University, Hlavova 8, 128 43 Prague 2, Czech Republic.
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Targeted Gold Nanoparticle⁻Oligonucleotide Contrast Agents in Combination with a New Local Voxel-Wise MRI Analysis Algorithm for In Vitro Imaging of Triple-Negative Breast Cancer. NANOMATERIALS 2019; 9:nano9050709. [PMID: 31067749 PMCID: PMC6566234 DOI: 10.3390/nano9050709] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Revised: 04/26/2019] [Accepted: 04/28/2019] [Indexed: 01/23/2023]
Abstract
Gold nanoparticles (GNPs) have tremendous potential as cancer-targeted contrast agents for diagnostic imaging. The ability to modify the particle surface with both disease-targeting molecules (such as the cancer-specific aptamer AS1411) and contrast agents (such as the gadolinium chelate Gd(III)-DO3A-SH) enables tailoring the particles for specific cancer-imaging and diagnosis. While the amount of image contrast generated by nanoparticle contrast agents is often low, it can be augmented with the assistance of computer image analysis algorithms. In this work, the ability of cancer-targeted gold nanoparticle–oligonucleotide conjugates to distinguish between malignant (MDA-MB-231) and healthy cells (MCF-10A) is tested using a T1-weighted image analysis algorithm based on three-dimensional, deformable model-based segmentation to extract the Volume of Interest (VOI). The gold nanoparticle/algorithm tandem was tested using contrast agent GNP-Gd(III)-DO3A-SH-AS1411) and nontargeted c-rich oligonucleotide (CRO) analogs and control (CTR) counterparts (GNP-Gd(III)-DO3A-SH-CRO/CTR) via in vitro studies. Remarkably, the cancer cells were notably distinguished from the nonmalignant cells, especially at nanomolar contrast agent concentrations. The T1-weighted image analysis algorithm provided similar results to the industry standard Varian software interface (VNMRJ) analysis of T1 maps at micromolar contrast agent concentrations, in which the VNMRJ produced a 19.5% better MRI contrast enhancement. However, our algorithm provided more sensitive and consistent results at nanomolar contrast agent concentrations, where our algorithm produced ~500% better MRI contrast enhancement.
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Urbanovský P, Kotek J, Carniato F, Botta M, Hermann P. Lanthanide Complexes of DO3A-(Dibenzylamino)methylphosphinate: Effect of Protonation of the Dibenzylamino Group on the Water-Exchange Rate and the Binding of Human Serum Albumin. Inorg Chem 2019; 58:5196-5210. [PMID: 30942072 DOI: 10.1021/acs.inorgchem.9b00267] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Protonation of a distant, noncoordinated group of metal-based magnetic resonance imaging contrast agents potentially changes their relaxivity. The effect of a positive charge of the drug on the human serum albumin (HSA)-drug interaction remains poorly understood as well. Accordingly, a (dibenzylamino)methylphosphinate derivative of 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was efficiently synthesized using pyridine as the solvent for a Mannich-type reaction of tBu3DO3A, formaldehyde, and Bn2NCH2PO2H2 ethyl ester. The ligand protonation and metal ion (Gd3+, Cu2+, and Zn2+) stability constants were similar to those of the parent DOTA, whereas the basicity of the side-chain amino group of the complexes (log KA = 5.8) was 1 order of magnitude lower than that of the free ligand (log KA = 6.8). The presence of one bound water molecule in both deprotonated and protonated forms of the gadolinium(III) complex was deduced from the solid-state X-ray diffraction data [gadolinium(III) and dysprosium(III)], from the square antiprism/twisted square antiprism (SA/TSA) isomer ratio along the lanthanide series, from the fluorescence data of the europium(III) complex, and from the 17O NMR measurements of the dysprosium(III) and gadolinium(III) complexes. In the gadolinium(III) complex with the deprotonated amino group, water exchange is extremely fast (τM = 6 ns at 25 °C), most likely thanks to the high abundance of the TSA isomer and to the presence of a proximate protonable group, which assists the water-exchange process. The interaction between lanthanide(III) complexes and HSA is pH-dependent, and the deprotonated form is bound much more efficaciously (∼13% and ∼70% bound complex at pH = 4 and 7, respectively). The relaxivities of the complex and its HSA adduct are also pH-dependent, and the latter is approximately 2-3 times increased at pH = 4-7. The relaxivity for the supramolecular HSA-complex adduct ( r1b) is as high as 52 mM-1 s-1 at neutral pH (at 20 MHz and 25 °C). The findings of this study stand as a proof-of-concept, showing the ability to manipulate an albumin-drug interaction, and thus the blood pool residence time of the drug, by introducing a positive charge in a side-chain amino group.
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Affiliation(s)
- Peter Urbanovský
- Department of Inorganic Chemistry , Universita Karlova (Charles University) , Hlavova 2030 , 12843 Prague 2 , Czech Republic
| | - Jan Kotek
- Department of Inorganic Chemistry , Universita Karlova (Charles University) , Hlavova 2030 , 12843 Prague 2 , Czech Republic
| | - Fabio Carniato
- Dipartimento di Scienze e Innovazione Tecnologica , Università del Piemonte Orientale "A. Avogadro" , Viale T. Michel 11 , 15121 Alessandria , Italy
| | - Mauro Botta
- Dipartimento di Scienze e Innovazione Tecnologica , Università del Piemonte Orientale "A. Avogadro" , Viale T. Michel 11 , 15121 Alessandria , Italy
| | - Petr Hermann
- Department of Inorganic Chemistry , Universita Karlova (Charles University) , Hlavova 2030 , 12843 Prague 2 , Czech Republic
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Zhou Z, Yang L, Gao J, Chen X. Structure-Relaxivity Relationships of Magnetic Nanoparticles for Magnetic Resonance Imaging. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1804567. [PMID: 30600553 PMCID: PMC6392011 DOI: 10.1002/adma.201804567] [Citation(s) in RCA: 201] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 10/17/2018] [Indexed: 05/17/2023]
Abstract
Magnetic nanoparticles (MNPs) have been extensively explored as magnetic resonance imaging (MRI) contrast agents. With the increasing complexity in the structure of modern MNPs, the classical Solomon-Bloembergen-Morgan and the outer-sphere quantum mechanical theories established on simplistic models have encountered limitations for defining the emergent phenomena of relaxation enhancement in MRI. Recent progress in probing MRI relaxivity of MNPs based on structural features at the molecular and atomic scales is reviewed, namely, the structure-relaxivity relationships, including size, shape, crystal structure, surface modification, and assembled structure. A special emphasis is placed on bridging the gaps between classical simplistic models and modern MNPs with elegant structural complexity. In the pursuit of novel MRI contrast agents, it is hoped that this review will spur the critical thinking for design and engineering of novel MNPs for MRI applications across a broad spectrum of research fields.
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Affiliation(s)
- Zijian Zhou
- † State Key Laboratory of Physical Chemistry of Solid Surfaces, The Key Laboratory for Chemical Biology of Fujian Province, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
- ‡ Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Lijiao Yang
- † State Key Laboratory of Physical Chemistry of Solid Surfaces, The Key Laboratory for Chemical Biology of Fujian Province, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Jinhao Gao
- † State Key Laboratory of Physical Chemistry of Solid Surfaces, The Key Laboratory for Chemical Biology of Fujian Province, and Department of Chemical Biology, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xiaoyuan Chen
- ‡ Laboratory of Molecular Imaging and Nanomedicine, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
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14
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Caravan P, Esteban-Gómez D, Rodríguez-Rodríguez A, Platas-Iglesias C. Water exchange in lanthanide complexes for MRI applications. Lessons learned over the last 25 years. Dalton Trans 2019; 48:11161-11180. [DOI: 10.1039/c9dt01948k] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Coordination chemistry offers convenient strategies to modulate the exchange of coordinated water molecules in lanthanide-based contrast agents.
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Affiliation(s)
- Peter Caravan
- The Institute for Innovation in Imaging and the A. A. Martinos Center for Biomedical Imaging
- Massachusetts General Hospital
- Harvard Medical School
- Charlestown
- USA
| | - David Esteban-Gómez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química
- Universidade da Coruña
- 15008 A Coruña
- Spain
| | - Aurora Rodríguez-Rodríguez
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química
- Universidade da Coruña
- 15008 A Coruña
- Spain
| | - Carlos Platas-Iglesias
- Centro de Investigacións Científicas Avanzadas (CICA) and Departamento de Química
- Universidade da Coruña
- 15008 A Coruña
- Spain
- The Institute for Innovation in Imaging and the A. A. Martinos Center for Biomedical Imaging
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15
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Kurbatov IA, Kharchenko VI, Mirochnik AG, Petrochenkova NV, Zhikhareva PA, Vovna VI. Vibrational Structure of Methacrylates Europium(Iii) and Lanthanum(Iii): Dft and Ir Spectroscopy Study. J STRUCT CHEM+ 2018. [DOI: 10.1134/s0022476618020105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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16
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Krchová T, Herynek V, Gálisová A, Blahut J, Hermann P, Kotek J. Eu(III) Complex with DO3A-amino-phosphonate Ligand as a Concentration-Independent pH-Responsive Contrast Agent for Magnetic Resonance Spectroscopy (MRS). Inorg Chem 2017; 56:2078-2091. [PMID: 28170242 DOI: 10.1021/acs.inorgchem.6b02749] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A new DOTA-like ligand H5do3aNP with a 2-[amino(methylphosphonic acid)]ethyl-coordinating pendant arm was prepared, and its coordinating properties were studied by NMR spectroscopy and potentiometry. The study revealed a rare slow exchange (on the 1H and 31P NMR time scale) between protonated and unprotonated complex species with a corresponding acidity constant pKA ∼ 8.0. This unusually slow time scale associated with protonation is caused by a significant geometric change from square-antiprismatic (SA) arrangement observed for protonated complex SA-[Eu(Hdo3aNP)]- to twisted-square-antiprismatic (TSA) arrangement found for deprotonated complex TSA-[Eu(do3aNP)]2-. This behavior results in simultaneous occurrence of the signals of both species in the 31P NMR spectra at approximately -118 and +70 ppm, respectively. Such an unprecedented difference in the chemical shifts between species differing by a proton is caused by a significant movement of the principal magnetic axis and by a change of phosphorus atom position in the coordination sphere of the central Eu(III) ion (i.e., by relative movement of the phosphorus atom with respect to the principal magnetic axis). It changes the sign of the paramagnetic contribution to the 31P NMR chemical shift. The properties discovered can be employed in the measurement of pH by MRS techniques as presented by proof-of-principle experiments on phantoms.
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Affiliation(s)
- Tereza Krchová
- Department of Inorganic Chemistry, Faculty of Science, Charles University , Hlavova 2030, Prague 2 128 43, Czech Republic
| | - Vít Herynek
- Department of Radiodiagnostic and Interventional Radiology, Magnetic Resonance Unit, Institute for Clinical and Experimental Medicine , Vídeňská 1958/9, Prague 4 140 21, Czech Republic
| | - Andrea Gálisová
- Department of Radiodiagnostic and Interventional Radiology, Magnetic Resonance Unit, Institute for Clinical and Experimental Medicine , Vídeňská 1958/9, Prague 4 140 21, Czech Republic
| | - Jan Blahut
- Department of Inorganic Chemistry, Faculty of Science, Charles University , Hlavova 2030, Prague 2 128 43, Czech Republic
| | - Petr Hermann
- Department of Inorganic Chemistry, Faculty of Science, Charles University , Hlavova 2030, Prague 2 128 43, Czech Republic
| | - Jan Kotek
- Department of Inorganic Chemistry, Faculty of Science, Charles University , Hlavova 2030, Prague 2 128 43, Czech Republic
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17
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Younis M, Darcos V, Paniagua C, Ronjat P, Lemaire L, Nottelet B, Garric X, Bakkour Y, El Nakat JH, Coudane J. MRI-visible polymer based on poly(methyl methacrylate) for imaging applications. RSC Adv 2016. [DOI: 10.1039/c5ra23646k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Macromolecular contrast agents are very attractive to afford efficient magnetic resonance imaging (MRI) visualization of implantable medical devices.
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Affiliation(s)
- Mira Younis
- Institut des Biomolécules Max Mousseron (IBMM)
- UMR 5247
- CNRS
- Université Montpellier
- ENSCM
| | - Vincent Darcos
- Institut des Biomolécules Max Mousseron (IBMM)
- UMR 5247
- CNRS
- Université Montpellier
- ENSCM
| | - Cédric Paniagua
- Institut des Biomolécules Max Mousseron (IBMM)
- UMR 5247
- CNRS
- Université Montpellier
- ENSCM
| | - Pauline Ronjat
- Institut des Biomolécules Max Mousseron (IBMM)
- UMR 5247
- CNRS
- Université Montpellier
- ENSCM
| | - Laurent Lemaire
- Micro et Nanomédecines Biomimétiques-MINT
- INSERM UMR-S1066
- Université Angers
- 49933 Angers Cedex 9
- France
| | - Benjamin Nottelet
- Institut des Biomolécules Max Mousseron (IBMM)
- UMR 5247
- CNRS
- Université Montpellier
- ENSCM
| | - Xavier Garric
- Institut des Biomolécules Max Mousseron (IBMM)
- UMR 5247
- CNRS
- Université Montpellier
- ENSCM
| | - Youssef Bakkour
- Laboratory of Applied Chemistry
- Faculty of Science III
- Lebanese University
- Tripoli
- Lebanon
| | | | - Jean Coudane
- Institut des Biomolécules Max Mousseron (IBMM)
- UMR 5247
- CNRS
- Université Montpellier
- ENSCM
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18
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Elhabiri M, Abada S, Sy M, Nonat A, Choquet P, Esteban-Gómez D, Cassino C, Platas-Iglesias C, Botta M, Charbonnière LJ. Importance of Outer-Sphere and Aggregation Phenomena in the Relaxation Properties of Phosphonated Gadolinium Complexes with Potential Applications as MRI Contrast Agents. Chemistry 2015; 21:6535-46. [DOI: 10.1002/chem.201500155] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Indexed: 11/10/2022]
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19
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Synthesis of bifunctional chelating agents based on mono and diphosphonic derivatives of diethylenetriaminepentaacetic acid. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.05.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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20
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Webber BC, Woods M. The confluence of structure and dynamics in lanthanide(III) chelates: how dynamics help define structure in solution. Dalton Trans 2014; 43:251-8. [PMID: 24100299 DOI: 10.1039/c3dt52143e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Coordination exchange processes tend to dominate the solution state behaviour of lanthanide chelates and generally prohibit the study of small conformational changes. In this article we take advantage of coordinatively rigid Eu(3+) chelates to examine the small conformational changes that occur in these chelates as water dissociatively exchanges in and out of the inner coordination sphere. The results show that the time-averaged conformation of the chelate alters as the water exchange rate increases. This conformational change reflects a change in the hydration state (q/r(LnH)(6)) of the chelate. The hydration state has recently come to be expressed as two separate parameters q and r(LnH). However, these two parameters simultaneously describe the same structural considerations which in solution are indistinguishable and intrinsically related to, and dependent upon, the dissociative water exchange rate. This realization leads to the broader understanding that a solution state structure can only be appreciated with reference to the dynamics of the system.
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Affiliation(s)
- Benjamin C Webber
- Department of Chemistry, Portland State University, 1719 SW 10th Ave, Portland, OR 97201, USA.
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21
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Ma H, Xu Y, Meng Q, Zhang L, Wang R, Sun D. Synthesis, Structure, and Luminescent Properties of Three Coordination Compounds Based on in situGenerated Tetrazolate and Carboxylate Ligands. Z Anorg Allg Chem 2014. [DOI: 10.1002/zaac.201300641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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22
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Krchová T, Kotek J, Jirák D, Havlíčková J, Císařová I, Hermann P. Lanthanide(III) complexes of aminoethyl-DO3A as PARACEST contrast agents based on decoordination of the weakly bound amino group. Dalton Trans 2014; 42:15735-47. [PMID: 24051547 DOI: 10.1039/c3dt52031e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
2-Aminoethyl DOTA analogues with unsubstituted (H3L1), monomethylated (H3L2) and dimethylated (H3L3) amino groups were prepared by improved synthetic procedures. Their solid-state structures exhibit an extensive system of intramolecular hydrogen bonds, which is probably present in solution and leads to the rather high value of the last dissociation constant. The protonation sequence of H3L1 in solution corresponds to that found in the solid state. The stability constants of the H3L1 complexes with La(3+) and Gd(3+) (20.02 and 22.23, respectively) are similar to those of DO3A and the reduction of the pK(A) value of the pendant amino group from 10.51 in the free ligand to 6.06 and 5.83 in the La(3+) and Gd(3+) complexes, respectively, points to coordination of the amino group. It was confirmed in the solid state structure of the [Yb(L1)] complex, where disorder between the SA' and TSA' isomers was found. A similar situation is expected in solution, where a fast equilibration among the isomers hampers the unambiguous determination of the isomer ratio in solution. The PARACEST effect was observed in Eu(III)-H3L1/H3L2 and Yb(III)-H3L1/H3L2 complexes, being dependent on pH in the region of 4.5-7.5 and pH-independent in more alkaline solutions. The decrease of the PARACEST effect parallels with the increasing abundance of the complex protonated species, where the pendant amino group is not coordinating. Surprisingly, a small PARACEST effect was also observed in solutions of Eu(III)/Yb(III)-H3L3 complexes, where the pendant amino group is dimethylated. The effect is detectable in a narrow pH region, where both protonated and deprotonated complex species are present in equilibrium. The data points to the new mechanism of the PARACEST effect, where the slow coordination-decoordination of the pendant amine is coupled with the fast proton exchange between the free amino group and bulk water mediates the magnetization transfer. The pH-dependence of the effect was proved to be measurable by MRI and, thus, the complexes extend the family of pH-sensitive probes.
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Affiliation(s)
- Tereza Krchová
- Department of Inorganic Chemistry, Universita Karlova (Charles University), Hlavova 2030, 128 40 Prague 2, Czech Republic.
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23
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Pierre VC, Allen MJ, Caravan P. Contrast agents for MRI: 30+ years and where are we going? J Biol Inorg Chem 2014; 19:127-31. [PMID: 24414380 PMCID: PMC4075138 DOI: 10.1007/s00775-013-1074-5] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 12/08/2013] [Indexed: 12/21/2022]
Abstract
Thirty years ago, Schering filed the first patent application for a contrast agent for magnetic resonance imaging (MRI) covering the forefather of the gadolinium contrast agents and still the most widely used gadolinium probe: gadolinium(III) diethylenetriaminepentaacetate (Magnevist). To date, 11 contrast agents have been approved by the US Food and Drug Administration for intravenous use. Coordination chemists have done a great deal to move the field forward. Our understanding of lanthanide chemistry now makes possible the design of complexes with long rotational correlation times, fast or slow water-exchange rates, high thermodynamic stabilities, and kinetic inertness, leading to sensitive and nontoxic contrast agents. Chemists did not stop there. The last few decades has seen the development of novel classes of probes that yield contrast through different mechanisms, such as paramagnetic chemical exchange saturation transfer agents. Thirty years since the first patent, chemists are still leading the way. The development of high-sensitivity contrast agents for high magnetic fields, safe probes for patients with kidney disorders, and multimodal, targeted, and responsive agents demonstrates that the field of contrast agents for MRI still has much to offer.
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Affiliation(s)
- Valérie C. Pierre
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455
| | - Matthew J. Allen
- Department of Chemistry, Wayne State University, Detroit, MI 48202
| | - Peter Caravan
- A. A. Martinos Center for Biomedical Imaging, Department of Radiology, MassachusettsGeneral Hospital and Harvard Medical School, Charlestown, MA 02129
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24
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Milne M, Lewis M, McVicar N, Suchy M, Bartha R, Hudson RHE. MRI ParaCEST agents that improve amide based pH measurements by limiting inner sphere water T2exchange. RSC Adv 2014. [DOI: 10.1039/c3ra43537g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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25
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Synthesis and Characterisation of First Generation Luminescent Lanthanide Complexes Suitable for Being Adapted for Uptake via the Mannose Receptor. ACTA ACUST UNITED AC 2013. [DOI: 10.1155/2013/498598] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
With the aim of directing lanthanide complex uptake via the mannose receptor, a first generation of luminescent lanthanide complexes has been developed with an α-D-mannose targeting motif. Four complexes were produced to investigate photophysical properties and determine the effect of the coordinated mannose residue on emission intensity. The free hydroxyls of the α-D-mannose residue quenched lanthanide phosphorescence due to their close proximity, though they did not bind the lanthanide centre as observed by q-values ≈1.0 for all complexes between pH 3 and 10. Fluorescent emission was found to vary significantly with pH, though phosphorescent emission was relatively insensitive to pH. This lack of pH sensitivity has the potential to provide stable emission for the visualisation of the endosome-lysosome system where acidic pH is often encountered.
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26
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Verma KD, Forgács A, Uh H, Beyerlein M, Maier ME, Petoud S, Botta M, Logothetis NK. New calcium-selective smart contrast agents for magnetic resonance imaging. Chemistry 2013; 19:18011-26. [PMID: 24353083 DOI: 10.1002/chem.201300169] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2013] [Revised: 08/25/2013] [Indexed: 11/06/2022]
Abstract
Calcium plays a vital role in the human body and especially in the central nervous system. Precise maintenance of Ca(2+) levels is very crucial for normal cell physiology and health. The deregulation of calcium homeostasis can lead to neuronal cell death and brain damage. To study this functional role played by Ca(2+) in the brain noninvasively by using magnetic resonance imaging, we have synthesized a new set of Ca(2+) -sensitive smart contrast agents (CAs). The agents were found to be highly selective to Ca(2+) in the presence of other competitive anions and cations in buffer and in physiological fluids. The structure of CAs comprises Gd(3+)-DO3A (DO3A=1,4,7-tris(carboxymethyl)-1,4,7,10-tetraazacyclododecane) coupled to a Ca(2+) chelator o-amino phenol-N,N,O-triacetate (APTRA). The agents are designed to sense Ca(2+) present in extracellular fluid of the brain where its concentration is relatively high, that is, 1.2-0.8 mM. The determined dissociation constant of the CAs to Ca(2+) falls in the range required to sense and report changes in extracellular Ca(2+) levels followed by an increase in neural activity. In buffer, with the addition of Ca(2+) the increase in relaxivity ranged from 100-157%, the highest ever known for any T1-based Ca(2+)-sensitive smart CA. The CAs were analyzed extensively by the measurement of luminescence lifetime measurement on Tb(3+) analogues, nuclear magnetic relaxation dispersion (NMRD), and (17)O NMR transverse relaxation and shift experiments. The results obtained confirmed that the large relaxivity enhancement observed upon Ca(2+) addition is due to the increase of the hydration state of the complexes together with the slowing down of the molecular rotation and the retention of a significant contribution of the water molecules of the second sphere of hydration.
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Affiliation(s)
- Kirti Dhingra Verma
- Max Planck Institute for Biological Cybernetics, Dept. of Physiology of Cognitive Processes, 72076 Tübingen (Germany); Present address: Case NFCR Center for Imaging Research, Dept. of Radiology, Case Western Reserve University, Cleveland, OH (USA).
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27
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Kotková Z, Helm L, Kotek J, Hermann P, Lukeš I. Gadolinium complexes of monophosphinic acid DOTA derivatives conjugated to cyclodextrin scaffolds: efficient MRI contrast agents for higher magnetic fields. Dalton Trans 2013; 41:13509-19. [PMID: 23018269 DOI: 10.1039/c2dt30858d] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Middle-molecular-weight MRI contrast agents based on conjugates of a phosphinic acid DOTA analogue, 1,4,7,10-tetraazacyclododecane-4,7,10-triacetic-1-{methyl[(4-aminophenyl)methyl]phosphinic acid} (DO3AP(ABn)), with amino-substituted cyclodextrins were prepared and studied by a variety of physico-chemical methods. The conjugates were formed by reaction of the corresponding isothiocyanate with per-6-amino-α/β-cyclodextrin and were complexed with the Ln(III) ion to get the final complexes, (LnL)(6)-α-CD and (LnL)(7)-β-CD. Solution structure of the complexes was estimated by investigation of the Eu(III) complexes. The Gd(III) conjugate complexes are endowed with a short water residence time (τ(M) ∼ 10-15 ns at 298 K) and a high abundance of the twisted-square antiprismatic diastereoisomer. They show a high (1)H relaxivity at high fields due to a convenient combination of the fast water exchange rate and the slow rate of the molecular tumbling given by their macromolecular nature. The (1)H relaxation enhancements per molecule of a contrast agent (CA) are very high reaching for a larger (GdL)(7)-β-CD conjugate ∼140 s(-1) mM(-1) and ∼100 s(-1) mM(-1) at 25 °C and magnetic fields 1.5 T and 3 T, respectively, which is the highest reported longitudinal relaxivity for kinetically stable contrast agents of an intermediate molecular mass (<10 kDa) with one water molecule in the first coordination sphere.
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Affiliation(s)
- Zuzana Kotková
- Department of Inorganic Chemistry, Charles University in Prague, Hlavova 2030, 128 40 Prague 2, Czech Republic
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28
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Strategies for optimizing water-exchange rates of lanthanide-based contrast agents for magnetic resonance imaging. Molecules 2013; 18:9352-81. [PMID: 23921796 PMCID: PMC3775326 DOI: 10.3390/molecules18089352] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Revised: 07/28/2013] [Accepted: 07/31/2013] [Indexed: 11/16/2022] Open
Abstract
This review describes recent advances in strategies for tuning the water-exchange rates of contrast agents for magnetic resonance imaging (MRI). Water-exchange rates play a critical role in determining the efficiency of contrast agents; consequently, optimization of water-exchange rates, among other parameters, is necessary to achieve high efficiencies. This need has resulted in extensive research efforts to modulate water-exchange rates by chemically altering the coordination environments of the metal complexes that function as contrast agents. The focus of this review is coordination-chemistry-based strategies used to tune the water-exchange rates of lanthanide(III)-based contrast agents for MRI. Emphasis will be given to results published in the 21st century, as well as implications of these strategies on the design of contrast agents.
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Avedano S, Botta M, Haigh JS, Longo D, Woods M. Coupling fast water exchange to slow molecular tumbling in Gd3+ chelates: why faster is not always better. Inorg Chem 2013; 52:8436-50. [PMID: 23841587 PMCID: PMC3769110 DOI: 10.1021/ic400308a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The influence of dynamics on solution state structure is a widely overlooked consideration in chemistry. Variations in Gd(3+) chelate hydration with changing coordination geometry and dissociative water exchange kinetics substantially impact the effectiveness (or relaxivity) of monohydrated Gd(3+) chelates as T1-shortening contrast agents for MRI. Theory shows that relaxivity is highly dependent upon the Gd(3+)-water proton distance (rGdH), and yet this distance is almost never considered as a variable in assessing the relaxivity of a Gd(3+) chelate as a potential contrast agent. The consequence of this omission can be seen when considering the relaxivity of isomeric Gd(3+) chelates that exhibit different dissociative water exchange kinetics. The results described herein show that the relaxivity of a chelate with "optimal" dissociative water exchange kinetics is actually lower than that of an isomeric chelate with "suboptimal" dissociative water exchange. When the rate of molecular tumbling of these chelates is slowed, an approach that has long been understood to increase relaxivity, the observed difference in relaxivity is increased with the more rapidly exchanging ("optimal") chelate exhibiting lower relaxivity than the "suboptimally" exchanging isomer. The difference between the chelates arises from a non-field-dependent parameter: either the hydration number (q) or rGdH. For solution state Gd(3+) chelates, changes in the values of q and rGdH are indistinguishable. These parametric expressions simply describe the hydration state of the chelate--i.e., the number and position of closely associating water molecules. The hydration state (q/rGdH(6)) of a chelate is intrinsically linked to its dissociative water exchange rate kex, and the interrelation of these parameters must be considered when examining the relaxivity of Gd(3+) chelates. The data presented herein indicate that the changes in the hydration parameter (q/rGdH(6)) associated with changing dissociative water exchange kinetics has a profound effect on relaxivity and suggest that achieving the highest relaxivities in monohydrated Gd(3+) chelates is more complicated than simply "optimizing" dissociative water exchange kinetics.
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Affiliation(s)
- Stefano Avedano
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale “Amedeo Avogadro”, Viale T. Michel 11, I-15121 Alessandria, Italy
| | - Mauro Botta
- Dipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale “Amedeo Avogadro”, Viale T. Michel 11, I-15121 Alessandria, Italy
| | - Julian S. Haigh
- Department of Chemistry, Portland State University, 1719 SW 10th Ave, Portland, OR 97201, USA
| | - Dario Longo
- Dipartimento di Biotecnologie Molecolari e Scienze della Salute and Molecular Imaging Center, Università di Torino, Via Nizza 52, I-10126 Torino, Italy
| | - Mark Woods
- Department of Chemistry, Portland State University, 1719 SW 10th Ave, Portland, OR 97201, USA
- Advanced Imaging Research Center, Oregon Health & Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239, USA
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Placidi MP, Botta M, Kálmán FK, Hagberg GE, Baranyai Z, Krenzer A, Rogerson AK, Tóth I, Logothetis NK, Angelovski G. Aryl-Phosphonate Lanthanide Complexes and Their Fluorinated Derivatives: Investigation of Their Unusual Relaxometric Behavior and Potential Application as Dual Frequency1H/19F MRI Probes. Chemistry 2013; 19:11644-60. [DOI: 10.1002/chem.201300763] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Indexed: 11/06/2022]
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Metal-directed syntheses of coordination polymers via in situ ligand reactions from the same precursor, 2-(1H-benzeimidazol-2-yl)-acetonitrile. INORG CHEM COMMUN 2013. [DOI: 10.1016/j.inoche.2013.02.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Lima LMP, Delgado R, Hermann P, Ševčík R, Lubal P, Carvalho HF, Martins AF, Tóth É, Geraldes CFGC. Tris(phosphonomethyl)cyclen Derivatives: Thermodynamic Stability, Kinetics, Solution Structure, and Relaxivity of Ln3+ Complexes. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201101335] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Frullano L, Caravan P. Strategies for the preparation of bifunctional gadolinium(III) chelators. Curr Org Synth 2011; 8:535-565. [PMID: 22375102 DOI: 10.2174/157017911796117250] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The development of gadolinium chelators that can be easily and readily linked to various substrates is of primary importance for the development high relaxation efficiency and/or targeted magnetic resonance imaging (MRI) contrast agents. Over the last 25 years a large number of bifunctional chelators have been prepared. For the most part, these compounds are based on ligands that are already used in clinically approved contrast agents. More recently, new bifunctional chelators have been reported based on complexes that show a more potent relaxation effect, faster complexation kinetics and in some cases simpler synthetic procedures. This review provides an overview of the synthetic strategies used for the preparation of bifunctional chelators for MRI applications.
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Affiliation(s)
- Luca Frullano
- Case Western Reserve University. 11100 Euclid Ave Cleveland, OH 44106
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Verwilst P, Eliseeva SV, Carron S, Vander Elst L, Burtea C, Dehaen G, Laurent S, Binnemans K, Muller RN, Parac-Vogt TN, De Borggraeve WM. A Modular Approach towards the Synthesis of Target-Specific MRI Contrast Agents. Eur J Inorg Chem 2011. [DOI: 10.1002/ejic.201100575] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Zheng SR, Cai SL, Fan J, Xiao TT, Zhang WG. Three new complexes synthesized from an imidazole-based dicarboxylate ligand containing hydroxymethyl group. INORG CHEM COMMUN 2011. [DOI: 10.1016/j.inoche.2011.03.065] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Jacques V, Dumas S, Sun WC, Troughton JS, Greenfield MT, Caravan P. High-relaxivity magnetic resonance imaging contrast agents. Part 2. Optimization of inner- and second-sphere relaxivity. Invest Radiol 2011; 45:613-24. [PMID: 20808234 DOI: 10.1097/rli.0b013e3181ee6a49] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
RATIONALE AND OBJECTIVES The observed relaxivity of gadolinium-based contrast agents has contributions from the water molecule(s) that bind directly to the gadolinium ion (inner-sphere water), long-lived water molecules and exchangeable protons that make up the second-sphere of coordination, and water molecules that diffuse near the contrast agent (outer-sphere). Inner- and second-sphere relaxivity can both be increased by optimization of the lifetimes of the water molecules and protons in these coordination spheres, the rotational motion of the complex, and the electronic relaxation of the gadolinium ion. We sought to identify new high-relaxivity contrast agents by systematically varying the donor atoms that bind directly to gadolinium to increase inner-sphere relaxivity and concurrently including substituents that influence the second-sphere relaxivity. METHODS Twenty gadolinium-1,4,7,10-tetraazacyclo-dodecane-N,N',N″,N'″-tetraacetato derivatives were prepared and their relaxivity determined in presence and absence of human serum albumin as a function of temperature and magnetic field. Data was analyzed to extract the underlying molecular parameters influencing relaxivity. Each compound had a common albumin-binding group and an inner-sphere donor set comprising the 4 tertiary amine N atoms from cyclen, an α-substituted acetate oxygen atom, 2 amide oxygen atoms, an inner-sphere water oxygen atom, and a variable donor group. Each amide nitrogen was substituted with different groups to promote hydrogen bonding with second-sphere water molecules. RESULTS Relativities at 0.47 and 1.4 T, 37°C, in serum albumin ranged from 16.0 to 58.1 mM(-1)s(-1) and from 12.3 to 34.8 mM(-1)s(-1), respectively. The reduction of inner-sphere water exchange typical of amide donor groups could be offset by incorporating a phosphonate or phenolate oxygen atom donor in the first coordination sphere, resulting in higher relaxivity. Amide nitrogen substitution with pendant phosphonate or carboxylate groups increased relaxivity by as much as 88% compared with the N-methyl amide analog. Second-sphere relaxivity contributed as much as 24 and 14 mM(-1)s(-1) at 0.47 and 1.4 T, respectively. CONCLUSIONS Water/proton exchange dynamics in the inner- and second-coordination sphere can be predictably tuned by choice of donor atoms and second-sphere substituents, resulting in high-relaxivity agents.
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High relaxivity magnetic resonance imaging contrast agents. Part 1. Impact of single donor atom substitution on relaxivity of serum albumin-bound gadolinium complexes. Invest Radiol 2011; 45:600-12. [PMID: 20808235 DOI: 10.1097/rli.0b013e3181ee5a9e] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
RATIONALE AND OBJECTIVES The donor atoms that bind to gadolinium in contrast agents influence inner-sphere water exchange and electronic relaxation, both of which determine observed relaxivity. The effect of these molecular parameters on relaxivity is greatest when the contrast agent is protein bound. We sought to determine an optimal donor atom set to yield high relaxivity compounds. METHODS A total of 38 gadolinium-1,4,7,10-tetraazacyclo-dodecane-N,N',N'',N'''-tetraacetato derivatives were prepared and relaxivity was determined in the presence and absence of human serum albumin as a function of temperature and magnetic field. Each compound had a common albumin-binding group and differed only by substitution of different donor groups at one of the macrocycle nitrogens. Oxygen-17 isotope relaxometry at 7.05 T was performed to estimate water exchange rates. RESULTS Changing a single donor atom resulted in changes in water exchange rates ranging across 3 orders of magnitude. Donor groups increased water exchange rate in the order: phosphonate ∼ phenolate > α-substituted acetate > acetate > hydroxamate ∼ sulfonamide > amide ∼ pyridyl ∼ imidazole. Relaxivites at 0.47 and 1.4 T, 37°C, ranged from 12.3 to 55.6 mM(-1)s(-1) and from 8.3 to 32.6 mM(-1)s(-1) respectively. Optimal relaxivities were observed when the donor group was an α-substituted acetate. Electronic relaxation was slowest for the acetate derivatives as well. CONCLUSIONS Water exchange dynamics and relaxivity can be predictably tuned by choice of donor atoms.
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Synthesis, Crystal Structures and Thermal Stabilities of Lanthanide Coordination Polymers with 5-Nitroisophthalate. J Inorg Organomet Polym Mater 2011. [DOI: 10.1007/s10904-011-9490-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Yin X, Fan J, Wang Z, Zhang WG. Synthesis, Crystal Structures, and Photoluminescence of Lanthanide Coordination Polymers with 4-Acetamidobenzoate. Z Anorg Allg Chem 2011. [DOI: 10.1002/zaac.201100035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Placidi MP, Engelmann J, Natrajan LS, Logothetis NK, Angelovski G. An aryl-phosphonate appended macrocyclic platform for lanthanide based bimodal imaging agents. Chem Commun (Camb) 2011; 47:11534-6. [DOI: 10.1039/c1cc14437e] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Zheng SR, Cai SL, Pan M, Fan J, Xiao TT, Zhang WG. The construction of coordination networks based on imidazole-based dicarboxylate ligand containing hydroxymethyl group. CrystEngComm 2011. [DOI: 10.1039/c0ce00369g] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Campello MPC, Lacerda S, Santos IC, Pereira GA, Geraldes CFGC, Kotek J, Hermann P, Vanek J, Lubal P, Kubícek V, Tóth E, Santos I. Lanthanide(III) complexes of 4,10-bis(phosphonomethyl)-1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (trans-H6do2a2p) in solution and in the solid state: structural studies along the series. Chemistry 2010; 16:8446-65. [PMID: 20540046 DOI: 10.1002/chem.201000320] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Complexes of 4,10-bis(phosphonomethyl)-1,4,7,10-tetraazacyclododecane-1,7-diacetic acid (trans-H(6)do2a2p, H(6)L) with transition metal and lanthanide(III) ions were investigated. The stability constant values of the divalent and trivalent metal-ion complexes are between the corresponding values of H(4)dota and H(8)dotp complexes, as a consequence of the ligand basicity. The solid-state structures of the ligand and of nine lanthanide(III) complexes were determined by X-ray diffraction. All the complexes are present as twisted-square-antiprismatic isomers and their structures can be divided into two series. The first one involves nona-coordinated complexes of the large lanthanide(III) ions (Ce, Nd, Sm) with a coordinated water molecule. In the series of Sm, Eu, Tb, Dy, Er, Yb, the complexes are octa-coordinated only by the ligand donor atoms and their coordination cages are more irregular. The formation kinetics and the acid-assisted dissociation of several Ln(III)-H(6)L complexes were investigated at different temperatures and compared with analogous data for complexes of other dota-like ligands. The [Ce(L)(H(2)O)](3-) complex is the most kinetically inert among complexes of the investigated lanthanide(III) ions (Ce, Eu, Gd, Yb). Among mixed phosphonate-acetate dota analogues, kinetic inertness of the cerium(III) complexes is increased with a higher number of phosphonate arms in the ligand, whereas the opposite is true for europium(III) complexes. According to the (1)H NMR spectroscopic pseudo-contact shifts for the Ce-Eu and Tb-Yb series, the solution structures of the complexes reflect the structures of the [Ce(HL)(H(2)O)](2-) and [Yb(HL)](2-) anions, respectively, found in the solid state. However, these solution NMR spectroscopic studies showed that there is no unambiguous relation between (31)P/(1)H lanthanide-induced shift (LIS) values and coordination of water in the complexes; the values rather express a relative position of the central ions between the N(4) and O(4) planes.
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Affiliation(s)
- M Paula C Campello
- Departamento de Química, Instituto Tecnológico e Nuclear, Estrada Nacional 10, 2686-953 Sacavém, Portugal
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Kotková Z, Kotek J, Jirák D, Jendelová P, Herynek V, Berková Z, Hermann P, Lukeš I. Cyclodextrin-Based Bimodal Fluorescence/MRI Contrast Agents: An Efficient Approach to Cellular Imaging. Chemistry 2010; 16:10094-102. [DOI: 10.1002/chem.200903519] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Ye S, Fang L, Lu Y, Lin Z, Xue G. Praseodymium/Polyureasulfone Complexes with Unusual Thermal, Luminescent and Magnetic Properties. MACROMOL CHEM PHYS 2010. [DOI: 10.1002/macp.201000027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wang J, Fan J, Guo L, Yin X, Wang Z, Zhang W. Synthesis, crystal structures and photoluminescent properties of lanthanide supramolecular complexes with 4-oxo-1(4H)-quinolineacetate. J SOLID STATE CHEM 2010. [DOI: 10.1016/j.jssc.2009.12.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Fan J, Wang ZH, Yang M, Yin X, Zhang WG, Huang ZF, Zeng RH. Controlled synthesis, structures and properties of one-, two-, and three-dimensional lanthanide coordination polymers based on (8-quinolyloxy)acetate. CrystEngComm 2010. [DOI: 10.1039/b910219a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Mamedov I, Táborský P, Lubal P, Laurent S, Vander Elst L, Mayer HA, Logothetis NK, Angelovski G. Relaxometric, Thermodynamic and Kinetic Studies of Lanthanide(III) Complexes of DO3A‐Based Propylphosphonates. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900149] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Ilgar Mamedov
- Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Spemannstr. 38, 72076 Tübingen, Germany, Fax: +49‐7071‐601‐919
| | - Petr Táborský
- Department of Chemistry, Masaryk University Kotlářská 2, 611 37 Brno, Czech Republic, Fax: +420‐549‐49‐2494
| | - Přemysl Lubal
- Department of Chemistry, Masaryk University Kotlářská 2, 611 37 Brno, Czech Republic, Fax: +420‐549‐49‐2494
| | - Sophie Laurent
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory, University of Mons, Mons, Belgium
| | - Luce Vander Elst
- Department of General, Organic and Biomedical Chemistry, NMR and Molecular Imaging Laboratory, University of Mons, Mons, Belgium
| | - Hermann A. Mayer
- Department for Inorganic Chemistry, Eberhard‐Karls‐Universität Tübingen, Tübingen, Germany
| | - Nikos K. Logothetis
- Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Spemannstr. 38, 72076 Tübingen, Germany, Fax: +49‐7071‐601‐919
- Imaging Science and Biomedical Engineering, University of Manchester, Manchester, United Kingdom
| | - Goran Angelovski
- Physiology of Cognitive Processes, Max Planck Institute for Biological Cybernetics, Spemannstr. 38, 72076 Tübingen, Germany, Fax: +49‐7071‐601‐919
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Młynarz P, Rydzewska A, Śliwińska S, Szymczyk M. The Aza-α-aminophosphonate Macrocycle. PHOSPHORUS SULFUR 2009. [DOI: 10.1080/10426500902947823] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Piotr Młynarz
- a Department of Chemistry , Wrocław University of Technology , Wrocław, Poland
| | - Agata Rydzewska
- a Department of Chemistry , Wrocław University of Technology , Wrocław, Poland
| | - Sylwia Śliwińska
- a Department of Chemistry , Wrocław University of Technology , Wrocław, Poland
| | - Monika Szymczyk
- a Department of Chemistry , Wrocław University of Technology , Wrocław, Poland
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Caravan P, Farrar CT, Frullano L, Uppal R. Influence of molecular parameters and increasing magnetic field strength on relaxivity of gadolinium- and manganese-based T1 contrast agents. CONTRAST MEDIA & MOLECULAR IMAGING 2009; 4:89-100. [PMID: 19177472 DOI: 10.1002/cmmi.267] [Citation(s) in RCA: 377] [Impact Index Per Article: 25.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Simulations were performed to understand the relative contributions of molecular parameters to longitudinal (r(1)) and transverse (r(2)) relaxivity as a function of applied field, and to obtain theoretical relaxivity maxima over a range of fields to appreciate what relaxivities can be achieved experimentally. The field-dependent relaxivities of a panel of gadolinium and manganese complexes with different molecular parameters, water exchange rates, rotational correlation times, hydration state, etc. were measured to confirm that measured relaxivities were consistent with theory. The design tenets previously stressed for optimizing r(1) at low fields (very slow rotational motion; chelate immobilized by protein binding; optimized water exchange rate) do not apply at higher fields. At 1.5 T and higher fields, an intermediate rotational correlation time is desired (0.5-4 ns), while water exchange rate is not as critical to achieving a high r(1). For targeted applications it is recommended to tether a multimer of metal chelates to a protein-targeting group via a long flexible linker to decouple the slow motion of the protein from the water(s) bound to the metal ions. Per ion relaxivities of 80, 45, and 18 mM(-1) s(-1) at 1.5, 3 and 9.4 T, respectively, are feasible for Gd(3+) and Mn(2+) complexes.
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Affiliation(s)
- Peter Caravan
- A. A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital and Department of Radiology, Harvard Medical School, 149 Thirteenth St, Charlestown, MA 02129, USA.
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