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Psatha K, Kollipara L, Drakos E, Deligianni E, Brintakis K, Patsouris E, Sickmann A, Rassidakis GZ, Aivaliotis M. Interruption of p53-MDM2 Interaction by Nutlin-3a in Human Lymphoma Cell Models Initiates a Cell-Dependent Global Effect on Transcriptome and Proteome Level. Cancers (Basel) 2023; 15:3903. [PMID: 37568720 PMCID: PMC10417430 DOI: 10.3390/cancers15153903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/22/2023] [Accepted: 06/28/2023] [Indexed: 08/13/2023] Open
Abstract
In most lymphomas, p53 signaling pathway is inactivated by various mechanisms independent to p53 gene mutations or deletions. In many cases, p53 function is largely regulated by alterations in the protein abundance levels by the action of E3 ubiquitin-protein ligase MDM2, targeting p53 to proteasome-mediated degradation. In the present study, an integrating transcriptomics and proteomics analysis was employed to investigate the effect of p53 activation by a small-molecule MDM2-antagonist, nutlin-3a, on three lymphoma cell models following p53 activation. Our analysis revealed a system-wide nutlin-3a-associated effect in all examined lymphoma types, identifying in total of 4037 differentially affected proteins involved in a plethora of pathways, with significant heterogeneity among lymphomas. Our findings include known p53-targets and novel p53 activation effects, involving transcription, translation, or degradation of protein components of pathways, such as a decrease in key members of PI3K/mTOR pathway, heat-shock response, and glycolysis, and an increase in key members of oxidative phoshosphorylation, autophagy and mitochondrial translation. Combined inhibition of HSP90 or PI3K/mTOR pathway with nutlin-3a-mediated p53-activation enhanced the apoptotic effects suggesting a promising strategy against human lymphomas. Integrated omic profiling after p53 activation offered novel insights on the regulatory role specific proteins and pathways may have in lymphomagenesis.
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Affiliation(s)
- Konstantina Psatha
- Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology, 70013 Heraklion, Greece; (K.P.); (E.D.)
- Department of Pathology, Medical School, University of Crete, 70013 Heraklion, Greece;
- First Department of Pathology, National and Kapodistrian University of Athens, 15772 Athens, Greece;
- Functional Proteomics and Systems Biology (FunPATh), Center for Interdisciplinary Research and Innovation (CIRI-AUTH), 54124 Thessaloniki, Greece
| | - Laxmikanth Kollipara
- Leibniz-Institut für Analytische Wissenschaften–ISAS–e.V., 44139 Dortmund, Germany; (L.K.); (A.S.)
| | - Elias Drakos
- Department of Pathology, Medical School, University of Crete, 70013 Heraklion, Greece;
| | - Elena Deligianni
- Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology, 70013 Heraklion, Greece; (K.P.); (E.D.)
| | - Konstantinos Brintakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, 71110 Heraklion, Greece;
| | - Eustratios Patsouris
- First Department of Pathology, National and Kapodistrian University of Athens, 15772 Athens, Greece;
| | - Albert Sickmann
- Leibniz-Institut für Analytische Wissenschaften–ISAS–e.V., 44139 Dortmund, Germany; (L.K.); (A.S.)
- Department of Chemistry, College of Physical Sciences, University of Aberdeen, Aberdeen AB24 3FX, UK
- Medizinische Fakultät, Medizinische Proteom-Center (MPC), Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - George Z. Rassidakis
- Department of Oncology-Pathology, Karolinska Institute, 17164 Stockholm, Sweden;
- Department of Hematopathology, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA
- Department of Clinical Pathology and Cancer Diagnostics, Karolinska University Hospital, Solna, 17176 Stockholm, Sweden
| | - Michalis Aivaliotis
- Institute of Molecular Biology and Biotechnology, Foundation of Research and Technology, 70013 Heraklion, Greece; (K.P.); (E.D.)
- Functional Proteomics and Systems Biology (FunPATh), Center for Interdisciplinary Research and Innovation (CIRI-AUTH), 54124 Thessaloniki, Greece
- Basic and Translational Research Unit, Special Unit for Biomedical Research and Education, School of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Laboratory of Biological Chemistry, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
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Kostopoulou A, Brintakis K, Sygletou M, Savva K, Livakas N, Pantelaiou MA, Dang Z, Lappas A, Manna L, Stratakis E. Laser-Induced Morphological and Structural Changes of Cesium Lead Bromide Nanocrystals. Nanomaterials 2022; 12:nano12040703. [PMID: 35215031 PMCID: PMC8879588 DOI: 10.3390/nano12040703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 02/15/2022] [Accepted: 02/17/2022] [Indexed: 02/01/2023]
Abstract
Metal halide perovskite nanocrystals, an emerging class of materials for advanced photonic and optoelectronic applications, are mainly fabricated with colloidal chemistry routes. On the quest for new properties according to application needs, new perovskite systems of various morphologies and levels of doping and alloying have been developed, often also involving post-synthesis reactions. Recently, laser irradiation in liquids has been utilized as a fast method to synthesize or transform materials and interesting laser-induced transformations on nanocrystals were induced. These studies in general have been limited to small nanocrystals (~15 nm). In the case of halide perovskites, fragmentation or anion exchange have been observed in such laser-based processes, but no crystal structure transformations were actually observed or deliberately studied. Nanocrystals are more sensitive to light exposure compared to the corresponding bulk crystals. Additional factors, such as size, morphology, the presence of impurities, and others, can intricately affect the photon absorption and heat dissipation in nanocrystal suspensions during laser irradiation. All these factors can play an important role in the final morphologies and in the time required for these transformations to unfold. In the present work, we have employed a 513 nm femtosecond (fs) laser to induce different transformations in large nanocrystals, in which two phases coexist in the same particle (Cs4PbBr6/CsPbBr3 nanohexagons of ~100 nm), dispersed in dichlorobenzene. These transformations include: (i) the exfoliation of the primary nanohexagons and partial anion exchange; (ii) fragmentation in smaller nanocubes and partial anion exchange; (iii) side-by-side-oriented attachment, fusion, and formation of nanoplatelets and complete anion exchange; (iv) side-by-side attachment, fusion, and formation of nanosheets. Partial or complete Br-Cl anion exchange in the above transformations was triggered by the partial degradation of dichlorobenzene. In addition to the detailed analysis of the various nanocrystal morphologies observed in the various transformations, the structure–photoluminescence relationships for the different samples were analyzed and discussed.
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Affiliation(s)
- Athanasia Kostopoulou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
- Correspondence: (A.K.); (K.B.); (E.S.); Tel.: +30-2810-391874 (A.K.); +30-2810-391874 (K.B.); +30-2810-391274 (E.S.)
| | - Konstantinos Brintakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
- Correspondence: (A.K.); (K.B.); (E.S.); Tel.: +30-2810-391874 (A.K.); +30-2810-391874 (K.B.); +30-2810-391274 (E.S.)
| | - Maria Sygletou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
| | - Kyriaki Savva
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
| | - Nikolaos Livakas
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
| | - Michaila Akathi Pantelaiou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
| | - Zhiya Dang
- Nanochemistry, Istituto Italiano di Tecnologia, 16163 Genova, Italy; (Z.D.); (L.M.)
| | - Alexandros Lappas
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
| | - Liberato Manna
- Nanochemistry, Istituto Italiano di Tecnologia, 16163 Genova, Italy; (Z.D.); (L.M.)
| | - Emmanuel Stratakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, 71110 Heraklion, Greece; (M.S.); (K.S.); (N.L.); (M.A.P.); (A.L.)
- Department of Physics, University of Crete, 71003 Heraklion, Greece
- Correspondence: (A.K.); (K.B.); (E.S.); Tel.: +30-2810-391874 (A.K.); +30-2810-391874 (K.B.); +30-2810-391274 (E.S.)
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Konidakis I, Brintakis K, Kostopoulou A, Demeridou I, Kavatzikidou P, Stratakis E. Highly luminescent and ultrastable cesium lead bromide perovskite patterns generated in phosphate glass matrices. Nanoscale 2020; 12:13697-13707. [PMID: 32573581 DOI: 10.1039/d0nr03254a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Owing to their exceptional optoelectronic properties, all-inorganic lead halide perovskites offer enormous potential for next generation photonic, light-emitting, and optoelectronic devices. However, their usage is significantly limited by their poor stability upon moisture exposure and lead toxicity issues. Moreover, many of the aforementioned applications rely on the development of confined perovskite patterns of various shapes and periodicities. Here we report a simple and low-temperature method enabling the controlled incorporation of photoluminescent all-inorganic metal halide PNCs into a silver phosphate glass (AgPO3) matrix which is transparent in most of the visible range. The developed fabrication protocol is based on a simple melting encapsulation process in which pre-synthesized perovskite crystals are inserted in the glass matrix, following the initial glass quenching. Using this novel approach, two types of composite perovskite glasses are prepared, one that hosts perovskite isles and the second in which a thin perovskite layer is embedded beneath the glass surface. Both types of composite glasses exhibit remarkable photoluminescence stability when compared to the ambient air-exposed perovskite crystals. More importantly, by means of a simple and fast cw-laser processing technique, we demonstrate the development of encapsulated dotted perovskite micropatterns within the composite perovskite glass. The ability of the proposed system to resolve stability and lead toxicity issues, coupled with the facile formation of highly luminescent perovskite patterns pave the way towards the broad exploitation of perovskite crystals in photonic applications.
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Affiliation(s)
- Ioannis Konidakis
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), 71110 Heraklion, Crete, Greece.
| | - Konstantinos Brintakis
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), 71110 Heraklion, Crete, Greece.
| | - Athanasia Kostopoulou
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), 71110 Heraklion, Crete, Greece.
| | - Ioanna Demeridou
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), 71110 Heraklion, Crete, Greece. and Physics Department, University of Crete, 71003 Heraklion, Crete, Greece
| | - Paraskevi Kavatzikidou
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), 71110 Heraklion, Crete, Greece.
| | - Emmanuel Stratakis
- Institute of Electronic Structure and Laser (IESL), Foundation for Research and Technology-Hellas (FORTH), 71110 Heraklion, Crete, Greece. and Physics Department, University of Crete, 71003 Heraklion, Crete, Greece
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Kostopoulou A, Brintakis K, Serpetzoglou E, Stratakis E. Laser-Assisted Fabrication for Metal Halide Perovskite-2D Nanoconjugates: Control on the Nanocrystal Density and Morphology. Nanomaterials (Basel) 2020; 10:E747. [PMID: 32295209 PMCID: PMC7221537 DOI: 10.3390/nano10040747] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/02/2020] [Accepted: 04/09/2020] [Indexed: 12/24/2022]
Abstract
We report on a facile and rapid photo-induced process to conjugate graphene-based materials with metal-halide perovskite nanocrystals. We show that a small number of laser pulses is sufficient to decorate the 2-dimensional (2D) flakes with metal-halide nanocrystals without affecting their primary morphology. At the same time, the density of anchored nanocrystals could be finely tuned by the number of irradiation pulses. This facile and rapid room temperature method provides unique opportunities for the design and development of perovskite-2D nanoconjugates, exhibiting synergetic functionality by combining nanocrystals of different morphologies and chemical phases with various 2D materials.
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Affiliation(s)
- Athanasia Kostopoulou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, 71110 Heraklion, Crete, Greece; (K.B.); (E.S.)
| | - Konstantinos Brintakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, 71110 Heraklion, Crete, Greece; (K.B.); (E.S.)
| | - Efthymis Serpetzoglou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, 71110 Heraklion, Crete, Greece; (K.B.); (E.S.)
- Department of Physics, University of Crete, 71003 Heraklion, Crete, Greece
| | - Emmanuel Stratakis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, 71110 Heraklion, Crete, Greece; (K.B.); (E.S.)
- Department of Physics, University of Crete, 71003 Heraklion, Crete, Greece
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Brintakis K, Gagaoudakis E, Kostopoulou A, Faka V, Argyrou A, Binas V, Kiriakidis G, Stratakis E. Ligand-free all-inorganic metal halide nanocubes for fast, ultra-sensitive and self-powered ozone sensors. Nanoscale Adv 2019; 1:2699-2706. [PMID: 36132711 PMCID: PMC9419230 DOI: 10.1039/c9na00219g] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 05/22/2019] [Indexed: 05/30/2023]
Abstract
Ligand-free all-inorganic lead halide nanocubes have been investigated as ozone sensing materials operating at room temperature. It is found that the nanocubes, crystallined in the orthorhombic CsPbBr3 structure, can operate at room temperature, be self-powered and exhibit high sensitivity and remarkable repeatability. More importantly, they demonstrate higher sensitivity (54% in 187 ppb) and faster response and recovery times compared to hybrid lead mixed halide perovskite (CH3NH3PbI3-x Cl x ) layers, which is the only lead halide perovskite material tested for ozone sensing, to date. Following the exposure to an ozone environment, the stoichiometry and the morphology of the nanocubes remain unaltered. The facile and easy fabrication process together with the high responsivity and stability to the ozone environment makes the bare CsPbBr3 nanocubes a promising material for sensing applications. The sensing properties of the nanoparticulate metal halides presented here provide new exciting opportunities towards engineering reliable and cheap sensing elements for room-temperature operated and self-powered sensors.
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Affiliation(s)
- K Brintakis
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
| | - E Gagaoudakis
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
- University of Crete, Department of Physics 710 03 Heraklion Crete Greece
| | - A Kostopoulou
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
| | - V Faka
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
- University of Crete, Department of Physics 710 03 Heraklion Crete Greece
- University of Crete, Department of Materials Science and Technology 710 03 Heraklion Crete Greece
| | - A Argyrou
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
- University of Crete, Department of Materials Science and Technology 710 03 Heraklion Crete Greece
| | - V Binas
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
- University of Crete, Department of Physics 710 03 Heraklion Crete Greece
- Crete Center for Quantum Complexity and Nanotechnology, Department of Physics, University of Crete 71003 Heraklion Greece
| | - G Kiriakidis
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
- University of Crete, Department of Physics 710 03 Heraklion Crete Greece
| | - E Stratakis
- Institute of Electronic Structure & Laser (IESL), Foundation for Research and Technology (FORTH) Hellas P.O. Box 1385 Heraklion 70013 Crete Greece
- University of Crete, Department of Physics 710 03 Heraklion Crete Greece
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Kostopoulou A, Brintakis K, Fragogeorgi E, Anthousi A, Manna L, Begin-Colin S, Billotey C, Ranella A, Loudos G, Athanassakis I, Lappas A. Iron Oxide Colloidal Nanoclusters as Theranostic Vehicles and Their Interactions at the Cellular Level. Nanomaterials (Basel) 2018; 8:E315. [PMID: 29747449 PMCID: PMC5977329 DOI: 10.3390/nano8050315] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 05/04/2018] [Accepted: 05/04/2018] [Indexed: 01/10/2023]
Abstract
Advances in surfactant-assisted chemical approaches have led the way for the exploitation of nanoscale inorganic particles in medical diagnosis and treatment. In this field, magnetically-driven multimodal nanotools that perform both detection and therapy, well-designed in size, shape and composition, are highly advantageous. Such a theranostic material—which entails the controlled assembly of smaller (maghemite) nanocrystals in a secondary motif that is highly dispersible in aqueous media—is discussed here. These surface functionalized, pomegranate-like ferrimagnetic nanoclusters (40⁻85 nm) are made of nanocrystal subunits that show a remarkable magnetic resonance imaging contrast efficiency, which is better than that of the superparamagnetic contrast agent Endorem©. Going beyond this attribute and with their demonstrated low cytotoxicity in hand, we examine the critical interaction of such nanoprobes with cells at different physiological environments. The time-dependent in vivo scintigraphic imaging of mice experimental models, combined with a biodistribution study, revealed the accumulation of nanoclusters in the spleen and liver. Moreover, the in vitro proliferation of spleen cells and cytokine production witnessed a size-selective regulation of immune system cells, inferring that smaller clusters induce mainly inflammatory activities, while larger ones induce anti-inflammatory actions. The preliminary findings corroborate that the modular chemistry of magnetic iron oxide nanoclusters stimulates unexplored pathways that could be driven to alter their function in favor of healthcare.
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Affiliation(s)
- Athanasia Kostopoulou
- Institute of Electronic Structure and Laser, Foundation for the Research and Technology, Hellas, Vassilika Vouton, 711 10 Heraklion, Greece.
| | - Konstantinos Brintakis
- Institute of Electronic Structure and Laser, Foundation for the Research and Technology, Hellas, Vassilika Vouton, 711 10 Heraklion, Greece.
| | - Eirini Fragogeorgi
- Institute of Nuclear & Radiological Sciences, Technology, Energy & Safety, NCSR "Demokritos", 153 41 Aghia Paraskevi, Athens, Greece.
| | - Amalia Anthousi
- Department of Biology, University of Crete, Vassilika Vouton, 710 03 Heraklion, Greece.
| | - Liberato Manna
- Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy.
| | - Sylvie Begin-Colin
- Université de Strasbourg, CNRS, Institut de Physique et Chimie des Matériaux de Strasbourg, UMR 7504, F-67034 Strasbourg, France.
| | - Claire Billotey
- Université de Lyon, Université Jean Monnet, EA 3738, Ciblage Thérapeutique en Oncologie, UJM-UCBL-HCL, Hôpital E. Herriot, 5 place d'Arsonval, 69437 Lyon CEDEX 03, France.
| | - Anthi Ranella
- Institute of Electronic Structure and Laser, Foundation for the Research and Technology, Hellas, Vassilika Vouton, 711 10 Heraklion, Greece.
| | - George Loudos
- Bioemission Technology Solutions, Alexandras 116, 117 42 Athens, Greece.
- Department of Biomedical Engineering, Technological Educational Institute, 122 10 Egaleo, Athens, Greece.
| | - Irene Athanassakis
- Department of Biology, University of Crete, Vassilika Vouton, 710 03 Heraklion, Greece.
| | - Alexandros Lappas
- Institute of Electronic Structure and Laser, Foundation for the Research and Technology, Hellas, Vassilika Vouton, 711 10 Heraklion, Greece.
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Kostopoulou A, Sygletou M, Brintakis K, Lappas A, Stratakis E. Low-temperature benchtop-synthesis of all-inorganic perovskite nanowires. Nanoscale 2017; 9:18202-18207. [PMID: 29159334 DOI: 10.1039/c7nr06404g] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A facile, low-temperature precipitation-based method is utilized for the synthesis of ultra-thin and highly uniform cesium lead bromide perovskite nanowires (NWs). The reactions facilitate the NWs' crystalline nature over micron-size lengths, while they impart tailored nanowire widths that range from the quantum confinement regime (∼7 nm) down to 2.6 nm. This colloidal synthesis approach is the first of its kind that is carried out on the work-bench, without demanding chemical synthesis equipment. Importantly, the NWs' photoluminescence is shown to improve over time, with no requirement for tedious post-synthesis surface treatment.
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Affiliation(s)
- A Kostopoulou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas, Vassilika Vouton, Heraklion, 71110, Crete, Greece.
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Kostopoulou A, Brintakis K, Vasilakaki M, Trohidou KN, Douvalis AP, Lascialfari A, Manna L, Lappas A. Assembly-mediated interplay of dipolar interactions and surface spin disorder in colloidal maghemite nanoclusters. Nanoscale 2014; 6:3764-76. [PMID: 24573414 DOI: 10.1039/c3nr06103e] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Controlled assembly of single-crystal, colloidal maghemite nanoparticles is facilitated via a high-temperature polyol-based pathway. Structural characterization shows that size-tunable nanoclusters of 50 and 86 nm diameters (D), with high dispersibility in aqueous media, are composed of ∼13 nm (d) crystallographically oriented nanoparticles. The interaction effects are examined against the increasing volume fraction, φ, of the inorganic magnetic phase that goes from individual colloidal nanoparticles (φ = 0.47) to clusters (φ = 0.72). The frozen-liquid dispersions of the latter exhibit weak ferrimagnetic behaviour at 300 K. Comparative Mössbauer spectroscopic studies imply that intra-cluster interactions come into play. New insight emerges from the clusters' temperature-dependent ac susceptibility that displays two maxima in χ''(T), with strong frequency dispersion. Scaling-law analysis together with the observed memory effects suggests that a superspin-glass state settles-in at TB ∼ 160-200 K, while at lower-temperatures, surface spin-glass freezing is established at Tf ∼ 40-70 K. In such nanoparticle-assembled systems, with increased φ, Monte Carlo simulations corroborate the role of the inter-particle dipolar interactions and that of the constituent nanoparticles' surface spin disorder in the emerging spin-glass dynamics.
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Affiliation(s)
- A Kostopoulou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas, Vassilika Vouton, Heraklion 71110, Greece.
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Kostopoulou A, Velu SKP, Thangavel K, Orsini F, Brintakis K, Psycharakis S, Ranella A, Bordonali L, Lappas A, Lascialfari A. Colloidal assemblies of oriented maghemite nanocrystals and their NMR relaxometric properties. Dalton Trans 2014; 43:8395-404. [DOI: 10.1039/c4dt00024b] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
1H-NMR relaxometric experiments over an extended frequency range show that ferrimagnetic colloidal nanoclusters exhibit enhanced transverse relaxivity, r2.
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Affiliation(s)
- Athanasia Kostopoulou
- Institute of Electronic Structure and Laser
- Foundation for Research and Technology – Hellas
- 71110 Heraklion, Greece
| | - Sabareesh K. P. Velu
- Dipartimento di Fisica
- Università degli studi di Milano and INSTM
- I-20133 Milano, Italy
| | - Kalaivani Thangavel
- Dipartimento di Fisica
- Università degli studi di Milano and INSTM
- I-20133 Milano, Italy
| | - Francesco Orsini
- Dipartimento di Fisica
- Università degli studi di Milano and INSTM
- I-20133 Milano, Italy
| | - Konstantinos Brintakis
- Institute of Electronic Structure and Laser
- Foundation for Research and Technology – Hellas
- 71110 Heraklion, Greece
- Department of Physics
- Aristotle University of Thessaloniki
| | - Stylianos Psycharakis
- Institute of Electronic Structure and Laser
- Foundation for Research and Technology – Hellas
- 71110 Heraklion, Greece
- Department of Medicine
- University of Crete
| | - Anthi Ranella
- Institute of Electronic Structure and Laser
- Foundation for Research and Technology – Hellas
- 71110 Heraklion, Greece
| | - Lorenzo Bordonali
- Dipartimento di Fisica
- Università degli studi di Pavia and INSTM
- Pavia, Italy
| | - Alexandros Lappas
- Institute of Electronic Structure and Laser
- Foundation for Research and Technology – Hellas
- 71110 Heraklion, Greece
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