1
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Ly HGT, Mihaylov TT, Proost P, Pierloot K, Harvey JN, Parac‐Vogt TN. Chemical Mimics of Aspartate‐Directed Proteases: Predictive and Strictly Specific Hydrolysis of a Globular Protein at Asp−X Sequence Promoted by Polyoxometalate Complexes Rationalized by a Combined Experimental and Theoretical Approach. Chemistry 2019; 25:14370-14381. [DOI: 10.1002/chem.201902675] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 08/13/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Hong Giang T. Ly
- Laboratory of Bioinorganic ChemistryDepartment of ChemistryKU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - Tzvetan T. Mihaylov
- Laboratory of Computational Coordination ChemistryDepartment of ChemistryKU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - Paul Proost
- Laboratory of Molecular ImmunologyRega InstituteDepartment of Microbiology, Immunology, and TransplantationKU Leuven Herestraat 49 3000 Leuven Belgium
| | - Kristine Pierloot
- Laboratory of Computational Coordination ChemistryDepartment of ChemistryKU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - Jeremy N. Harvey
- Laboratory of Computational Coordination ChemistryDepartment of ChemistryKU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
| | - Tatjana N. Parac‐Vogt
- Laboratory of Bioinorganic ChemistryDepartment of ChemistryKU Leuven Celestijnenlaan 200F 3001 Leuven Belgium
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2
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Zhou W, Zheng Y, Yuan G, Peng J. Three polyoxometalates-based organic–inorganic hybrids decorated with Cu–terpyridine complexes exhibiting dual functional electro-catalytic behaviors. Dalton Trans 2019; 48:2598-2605. [DOI: 10.1039/c8dt04945a] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Three new polyoxometalates-based organic–inorganic hybrids decorated with Cu–terpyridine complexes were prepared by using one-pot methods. Compounds 1–3 demonstrate discrepant dual functional electro-catalytic activities toward reduction of nitrite and oxidation of ascorbic acid.
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Affiliation(s)
- Wanli Zhou
- Faculty of Chemistry
- Tonghua Normal University
- Tonghua
- PR China
| | - Yanping Zheng
- Faculty of Chemistry
- Tonghua Normal University
- Tonghua
- PR China
| | - Gang Yuan
- Faculty of Chemistry
- Tonghua Normal University
- Tonghua
- PR China
| | - Jun Peng
- Key Laboratory of Polyoxometalate Science of Ministry of Education
- Faculty of Chemistry
- Northeast Normal University
- Changchun
- PR China
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3
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Monakhov K, Moors M, Kögerler P. Perspectives for Polyoxometalates in Single-Molecule Electronics and Spintronics. ADVANCES IN INORGANIC CHEMISTRY 2017. [DOI: 10.1016/bs.adioch.2016.12.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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4
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Luong TKN, Mihaylov TT, Absillis G, Shestakova P, Pierloot K, Parac-Vogt TN. Phosphate Ester Bond Hydrolysis Promoted by Lanthanide-Substituted Keggin-type Polyoxometalates Studied by a Combined Experimental and Density Functional Theory Approach. Inorg Chem 2016; 55:9898-9911. [PMID: 27657461 DOI: 10.1021/acs.inorgchem.6b01802] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Hydrolytic cleavage of 4-nitrophenyl phosphate (NPP), a commonly used DNA model substrate, was examined in the presence of series of lanthanide-substituted Keggin-type polyoxometalates (POMs) [Me2NH2]11[CeIII(PW11O39)2], [Me2NH2]10[CeIV(PW11O39)2] (abbreviated as (CeIV(PW11)2), and K4[EuPW11O39] by means of NMR and luminescence spectroscopies and density functional theory (DFT) calculations. Among the examined complexes, the Ce(IV)-substituted Keggin POM (CeIV(PW11)2) showed the highest reactivity, and its aqueous speciation was fully determined under different conditions of pD, temperature, concentration, and ionic strength by means of 31P and 31P diffusion-ordered NMR spectroscopy. The cleavage of the phosphoester bond of NPP in the presence of (CeIV(PW11)2) proceeded with an observed rate constant kobs = (5.31 ± 0.06) × 10-6 s-1 at pD 6.4 and 50 °C. The pD dependence of NPP hydrolysis exhibits a bell-shaped profile, with the fastest rate observed at pD 6.4. The formation constant (Kf = 127 M-1) and catalytic rate constant (kc = 19.41 × 10-5 s-1) for the NPP-Ce(IV)-Keggin POM complex were calculated, and binding between CeIV(PW11)2 and the phosphate group of NPP was also evidenced by the change of the chemical shift of the 31P nucleus in NPP upon addition of the POM complex. DFT calculations revealed that binding of NPP to the parent catalyst CeIV(PW11)2 is thermodynamically unlikely. On the contrary, formation of complexes with the monomeric 1:1 species, CeIVPW11, is considered to be more favorable, and the most stable complex, [CeIVPW11(H2O)2(NPP-κO)2]7-, was found to involve two NPP ligands coordinated to the CeIVcenter of CeIVPW11 in the monodentate fashion. The formation of such species is considered to be responsible for the hydrolytic activity of CeIV(PW11)2 toward phosphomonoesters. On the basis of these findings a principle mechanism for the hydrolysis of NPP by the POM is proposed.
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Affiliation(s)
| | | | | | - Pavletta Shestakova
- NMR Laboratory, Institute of Organic Chemistry with Centre of Phytochemistry, Bulgarian Academy of Sciences , Acad. G. Bontchev Str., B1.9, 1113 Sofia, Bulgaria
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Breitwieser R, Auvray T, Volatron F, Salzemann C, Ngo AT, Albouy PA, Proust A, Petit C. Binary Superlattices from {Mo132} Polyoxometalates and Maghemite Nanocrystals: Long-Range Ordering and Fine-Tuning of Dipole Interactions. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2016; 12:220-228. [PMID: 26578032 DOI: 10.1002/smll.201502127] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/19/2015] [Indexed: 06/05/2023]
Abstract
In the present article, the successful coassembly of spherical 6.2 nm maghemite (γ-Fe2O3) nanocrystals and giant polyoxometalates (POMs) such as 2.9 nm {Mo132} is demonstrated. To do so, colloidal solutions of oleic acid-capped γ-Fe2O3 and long-chain alkylammonium-encapsulated {Mo132 } dispersed in chloroform are mixed together and supported self-organized binary superlattices are obtained upon the solvent evaporation on immersed substrates. Both electronic microscopy and small angles X-ray scattering data reveal an AB-type structure and an enhanced structuration of the magnetic nanocrystals (MNCs) assembly with POMs in octahedral interstices. Therefore, {Mo132} acts as an efficient binder constituent for improving the nanocrystals ordering in 3D films. Interestingly, in the case of didodecyldimethylammonium (C12)-encapsulated POMs, the long-range ordered binary assemblies are obtained while preserving the nanocrystals magnetic properties due to weak POMs-MNCs interactions. On the other hand, POMs of larger effective diameter can be employed as spacer blocks for MNCs as shown by using {Mo132} capped with dioctadecyldimethylammonium (C18) displaying longer chains. In that case, it is shown that POMs can also be used for fine-tuning the dipolar interactions in γ-Fe2O3 nanocrystal assemblies.
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Affiliation(s)
- Romain Breitwieser
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 8232, Institut Parisien de Chimie Moléculaire, Université Pierre et Marie Curie, 4 place Jussieu, case courrier 42, F-75005, Paris CEDEX 05, France
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 8233, MONARIS, Case courrier, 52, Université Pierre et Marie Curie, 4 place Jussieu, F-75005, Paris, France
| | - Thomas Auvray
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 8232, Institut Parisien de Chimie Moléculaire, Université Pierre et Marie Curie, 4 place Jussieu, case courrier 42, F-75005, Paris CEDEX 05, France
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 8233, MONARIS, Case courrier, 52, Université Pierre et Marie Curie, 4 place Jussieu, F-75005, Paris, France
| | - Florence Volatron
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 8232, Institut Parisien de Chimie Moléculaire, Université Pierre et Marie Curie, 4 place Jussieu, case courrier 42, F-75005, Paris CEDEX 05, France
| | - Caroline Salzemann
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 8233, MONARIS, Case courrier, 52, Université Pierre et Marie Curie, 4 place Jussieu, F-75005, Paris, France
| | - Anh-Tu Ngo
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 8233, MONARIS, Case courrier, 52, Université Pierre et Marie Curie, 4 place Jussieu, F-75005, Paris, France
| | - Pierre-Antoine Albouy
- Laboratoire de Physique des solides, UMR CNRS 8502, Université Paris Sud, Bât. 510, 91405, Orsay CEDEX, France
| | - Anna Proust
- Sorbonne Universités, UPMC Univ Paris 06, CNRS UMR 8232, Institut Parisien de Chimie Moléculaire, Université Pierre et Marie Curie, 4 place Jussieu, case courrier 42, F-75005, Paris CEDEX 05, France
| | - Christophe Petit
- Sorbonne Universités, UPMC Univ Paris 06, CNRS, UMR 8233, MONARIS, Case courrier, 52, Université Pierre et Marie Curie, 4 place Jussieu, F-75005, Paris, France
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6
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Abramov PA, Peresypkina EV, Izarova NV, Vicent C, Zhdanov AA, Kompankov NB, Gutsul T, Sokolov MN. Polyoxoanions assembled by the condensation of vanadate, tungstate and selenite: solution studies and crystal structures of the mixed metal derivatives (NMe4)2Na2[WVI4VV2O19]·8H2O and (NMe4)4.83[(SeIV WVI4.57VV4.43O33)2(WVI(O)(H2O))(VVO)2.6]·10.57H2O. NEW J CHEM 2016. [DOI: 10.1039/c5nj00858a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of SeO32−/WO42−/VO43− gives a complex mixture of Lindqvist W–V anions and larger Se–W–V containing POMs.
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Affiliation(s)
- Pavel A. Abramov
- Nikolaev Institute of Inorganic Chemistry SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Eugenia V. Peresypkina
- Nikolaev Institute of Inorganic Chemistry SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
| | - Natalia V. Izarova
- Peter Grünberg Institute – PGI 6
- Forschungszentrum Jülich
- D-52425 Jülich
- Germany
| | - Cristian Vicent
- Serveis Centrals d'Instrumentació Científica
- Universitat Jaume I
- 12071 Castelló
- Spain
| | - Artem A. Zhdanov
- Nikolaev Institute of Inorganic Chemistry SB RAS
- Novosibirsk
- Russia
| | | | - Tatiana Gutsul
- Gitsu Institute of Electronic Engineering and Nanotechnologies
- Academy of Sciences of Moldova
- Chisinau
- MD-2028 Republic of Moldova
| | - Maxim N. Sokolov
- Nikolaev Institute of Inorganic Chemistry SB RAS
- Novosibirsk
- Russia
- Novosibirsk State University
- Novosibirsk
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7
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Ly HGT, Absillis G, Parac-Vogt TN. Influence of the amino acid side chain on peptide bond hydrolysis catalyzed by a dimeric Zr(iv)-substituted Keggin type polyoxometalate. NEW J CHEM 2016. [DOI: 10.1039/c5nj00561b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Structurally different dipeptides were hydrolyzed by [{α-PW11O39Zr-(μ-OH)(H2O)}2]8−. The rate constants were dependent on bulkiness and chemical nature of the dipeptide.
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8
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Wu P, Xue Q, Dong X, Zhang Y, Liu B, Hu H, Xue G. pH-Dependent assembly of three novel inorganic–organic hybrids based on different isopolymolybdates and CuI/II(bbx)nunits. CrystEngComm 2016. [DOI: 10.1039/c6ce00776g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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9
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Seemann KM, Luysberg M, Révay Z, Kudejova P, Sanz B, Cassinelli N, Loidl A, Ilicic K, Multhoff G, Schmid TE. Magnetic heating properties and neutron activation of tungsten-oxide coated biocompatible FePt core-shell nanoparticles. J Control Release 2014; 197:131-7. [PMID: 25445697 DOI: 10.1016/j.jconrel.2014.11.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 11/03/2014] [Accepted: 11/04/2014] [Indexed: 10/24/2022]
Abstract
Magnetic nanoparticles are highly desirable for biomedical research and treatment of cancer especially when combined with hyperthermia. The efficacy of nanoparticle-based therapies could be improved by generating radioactive nanoparticles with a convenient decay time and which simultaneously have the capability to be used for locally confined heating. The core-shell morphology of such novel nanoparticles presented in this work involves a polysilico-tungstate molecule of the polyoxometalate family as a precursor coating material, which transforms into an amorphous tungsten oxide coating upon annealing of the FePt core-shell nanoparticles. The content of tungsten atoms in the nanoparticle shell is neutron activated using cold neutrons at the Heinz Maier-Leibnitz (FRMII) neutron facility and thereby transformed into the radioisotope W-187. The sizeable natural abundance of 28% for the W-186 precursor isotope, a radiopharmaceutically advantageous gamma-beta ratio of γβ≈30% and a range of approximately 1mm in biological tissue for the 1.3MeV β-radiation are promising features of the nanoparticles' potential for cancer therapy. Moreover, a high temperature annealing treatment enhances the magnetic moment of nanoparticles in such a way that a magnetic heating effect of several degrees Celsius in liquid suspension - a prerequisite for hyperthermia treatment of cancer - was observed. A rise in temperature of approximately 3°C in aqueous suspension is shown for a moderate nanoparticle concentration of 0.5mg/ml after 15min in an 831kHz high-frequency alternating magnetic field of 250Gauss field strength (25mT). The biocompatibility based on a low cytotoxicity in the non-neutron-activated state in combination with the hydrophilic nature of the tungsten oxide shell makes the coated magnetic FePt nanoparticles ideal candidates for advanced radiopharmaceutical applications.
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Affiliation(s)
- K M Seemann
- Physik Department E21, Technische Universität München, D-85747 Garching, Germany; Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, D-85747 Garching, Germany.
| | - M Luysberg
- Peter Grünberg Institute (PGI-5) and Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, Research Centre Jülich, D-52425 Jülich, Germany
| | - Z Révay
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, D-85747 Garching, Germany
| | - P Kudejova
- Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universität München, D-85747 Garching, Germany
| | - B Sanz
- nanoScale Biomagnetics SL, 50012 Zaragoza, Spain
| | - N Cassinelli
- nanoScale Biomagnetics SL, 50012 Zaragoza, Spain
| | - A Loidl
- Experimentalphysik V, Center for Electronic Correlations and Magnetism, Universität Augsburg, D-86159 Augsburg, Germany
| | - K Ilicic
- Klinikum rechts d. Isar, Department of Radiooncology and HMGU München, CCG - Innate Immunity in Tumor Biology", Technische Universität München, D-81675 München, Germany
| | - G Multhoff
- Klinikum rechts d. Isar, Department of Radiooncology and HMGU München, CCG - Innate Immunity in Tumor Biology", Technische Universität München, D-81675 München, Germany
| | - T E Schmid
- Klinikum rechts d. Isar, Department of Radiooncology and HMGU München, CCG - Innate Immunity in Tumor Biology", Technische Universität München, D-81675 München, Germany
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10
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Luong TKN, Absillis G, Shestakova P, Parac-Vogt TN. Solution Speciation of the Dinuclear ZrIV-Substituted Keggin Polyoxometalate [{α-PW11O39Zr(μ-OH)(H2O)}2]8-and Its Reactivity towards DNA-Model Phosphodiester Hydrolysis. Eur J Inorg Chem 2014. [DOI: 10.1002/ejic.201402735] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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11
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Seemann K, Kuhn B. Multi-photon excited luminescence of magnetic FePt core-shell nanoparticles. BIOMEDICAL OPTICS EXPRESS 2014; 5:2446-57. [PMID: 25071977 PMCID: PMC4102377 DOI: 10.1364/boe.5.002446] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 06/20/2014] [Accepted: 06/23/2014] [Indexed: 05/24/2023]
Abstract
We present magnetic FePt nanoparticles with a hydrophilic, inert, and biocompatible silico-tungsten oxide shell. The particles can be functionalized, optically detected, and optically manipulated. To show the functionalization the fluorescent dye NOPS was bound to the FePt core-shell nanoparticles with propyl-triethoxy-silane linkers and fluorescence of the labeled particles were observed in ethanol (EtOH). In aqueous dispersion the NOPS fluorescence is quenched making them invisible using 1-photon excitation. However, we observe bright luminescence of labeled and even unlabeled magnetic core-shell nanoparticles with multi-photon excitation. Luminescence can be detected in the near ultraviolet and the full visible spectral range by near infrared multi-photon excitation. For optical manipulation, we were able to drag clusters of particles, and maybe also single particles, by a focused laser beam that acts as optical tweezers by inducing an electric dipole in the insulated metal nanoparticles. In a first application, we show that the luminescence of the core-shell nanoparticles is bright enough for in vivo multi-photon imaging in the mouse neocortex down to cortical layer 5.
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Affiliation(s)
- K.M. Seemann
- Physik Department E21, Technische Universität München, D-85748 Garching, Germany
- Forschungsneutronenquelle Heinz Maier-Leibnitz, Technische Universität München, D-85747 Garching, Germany
- These authors contributed equally
| | - B. Kuhn
- Optical Neuroimaging Unit, Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa 904-0495, Japan
- These authors contributed equally
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12
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Grinenval E, Bayard F, Basset JM, Lefebvre F. Formation of a Covalent Bond between a Polyoxometalate and Silica Covered by SiH Moieties. Inorg Chem 2014; 53:2022-9. [DOI: 10.1021/ic4023163] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Eva Grinenval
- CPE Lyon, CNRS, UMR C2P2, LCOMS, Bâtiment CPE Curien, Université Lyon 1 , 43 Boulevard du 11 Novembre 1918, F-69616 Villeurbanne, France
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13
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Villanneau R, Roucoux A, Beaunier P, Brouri D, Proust A. Simple procedure for vacant POM-stabilized palladium (0) nanoparticles in water: structural and dispersive effects of lacunary polyoxometalates. RSC Adv 2014. [DOI: 10.1039/c4ra03104k] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Metallic palladium nanoparticles have been generated by hydrogenation in very mild conditions of aqueous solutions of non-organometallic PdII-derivatives of heteropolytungstates.
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Affiliation(s)
- R. Villanneau
- Sorbonne Universités
- UPMC-Paris 06
- UMR 8232
- Institut Parisien de Chimie Moléculaire
- F-75005 Paris, France
| | - A. Roucoux
- Ecole Normale Supérieure de Chimie de Rennes
- UMR CNRS 6226
- F-35708 Rennes cedex 7, France
- Université européenne de Bretagne
- France
| | - P. Beaunier
- Sorbonne Universités
- UPMC-Paris 06
- UMR 7197
- Laboratoire de Réactivité de Surface
- F-75005 Paris, France
| | - D. Brouri
- Sorbonne Universités
- UPMC-Paris 06
- UMR 7197
- Laboratoire de Réactivité de Surface
- F-75005 Paris, France
| | - A. Proust
- Sorbonne Universités
- UPMC-Paris 06
- UMR 8232
- Institut Parisien de Chimie Moléculaire
- F-75005 Paris, France
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14
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Cheong S, Kim Y, Kwon T, Kim BJ, Cho J. Inorganic nanoparticle multilayers using photo-crosslinking layer-by-layer assembly and their applications in nonvolatile memory devices. NANOSCALE 2013; 5:12356-12364. [PMID: 24162469 DOI: 10.1039/c3nr04547a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We introduce a general and facile method for the preparation of organic/inorganic nanoparticle (NP) nanocomposite multilayer films that allows vertical growth of various NP layers (i.e., metal or transition metal oxide NPs) in a densely packed structure. Our approach is based on the successive photo-crosslinking layer-by-layer (LbL) assembly between hydrophobic ligands onto a NP surface and photoinitiator (PI) molecules. Therefore, our approach requires neither the additional surface modification needed for well-defined NPs synthesized in organic media nor the deposition step that inserts a polymer layer bridge between adjacent inorganic NP layers in the preparation of traditional LbL-assembled NP films. We also demonstrate that photo-crosslinking LbL-assembled (metal oxide NP)n films could be used as a nonvolatile memory layer without a high-temperature thermal treatment, unlike conventional vacuum-deposition- or sol-gel-derived memory devices, which require thermal treatments at temperatures greater than 200 °C. This robust method could open a facile route for the design of functional NP-based electronic devices.
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Affiliation(s)
- Sanghyuk Cheong
- Department of Chemical and Biological Engineering, Korea University, Anam-dong, Seongbuk-gu, Seoul 136-713, Korea.
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15
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Crespo P, de la Presa P, Marín P, Multigner M, Alonso JM, Rivero G, Yndurain F, González-Calbet JM, Hernando A. Magnetism in nanoparticles: tuning properties with coatings. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2013; 25:484006. [PMID: 24201075 DOI: 10.1088/0953-8984/25/48/484006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This paper reviews the effect of organic and inorganic coatings on magnetic nanoparticles. The ferromagnetic-like behaviour observed in nanoparticles constituted by materials which are non-magnetic in bulk is analysed for two cases: (a) Pd and Pt nanoparticles, formed by substances close to the onset of ferromagnetism, and (b) Au and ZnO nanoparticles, which were found to be surprisingly magnetic at the nanoscale when coated by organic surfactants. An overview of theories accounting for this unexpected magnetism, induced by the nanosize influence, is presented. In addition, the effect of coating magnetic nanoparticles with biocompatible metals, oxides or organic molecules is also reviewed, focusing on their applications.
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