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Verykokou S, Ioannidis C, Soile S, Angelopoulos C, Theodoridis K, Arampatzis AS, Assimopoulou AN, Christofilos D, Kapourani A, Pantazos I, Barmpalexis P, Boutsi AM, Potsiou C. The Role of Cone Beam Computed Tomography in Periodontology: From 3D Models of Periodontal Defects to 3D-Printed Scaffolds. J Pers Med 2024; 14:207. [PMID: 38392640 PMCID: PMC10890394 DOI: 10.3390/jpm14020207] [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: 01/01/2024] [Revised: 02/05/2024] [Accepted: 02/13/2024] [Indexed: 02/24/2024] Open
Abstract
The treatment of osseous defects around teeth is a fundamental concern within the field of periodontology. Over the years, the method of grafting has been employed to treat bone defects, underscoring the necessity for custom-designed scaffolds that precisely match the anatomical intricacies of the bone cavity to be filled, preventing the formation of gaps that could allow the regeneration of soft tissues. In order to create such a patient-specific scaffold (bone graft), it is imperative to have a highly detailed 3D representation of the bone defect, so that the resulting scaffold aligns with the ideal anatomical characteristics of the bone defect. In this context, this article implements a workflow for designing 3D models out of patient-specific tissue defects, fabricated as scaffolds with 3D-printing technology and bioabsorbable materials, for the personalized treatment of periodontitis. The workflow is based on 3D modeling of the hard tissues around the periodontal defect (alveolar bone and teeth), scanned from patients with periodontitis. Specifically, cone beam computed tomography (CBCT) data were acquired from patients and were used for the reconstruction of the 3D model of the periodontal defect. The final step encompasses the 3D printing of these scaffolds, employing Fused Deposition Modeling (FDM) technology and 3D-bioprinting, with the aim of verifying the design accuracy of the developed methodοlogy. Unlike most existing 3D-printed scaffolds reported in the literature, which are either pre-designed or have a standard structure, this method leads to the creation of highly detailed patient-specific grafts. Greater accuracy and resolution in the macroarchitecture of the scaffolds were achieved during FDM printing compared to bioprinting, with the standard FDM printing profile identified as more suitable in terms of both time and precision. It is easy to follow and has been successfully employed to create 3D models of periodontal defects and 3D-printed scaffolds for three cases of patients, proving its applicability and efficiency in designing and fabricating personalized 3D-printed bone grafts using CBCT data.
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Affiliation(s)
- Styliani Verykokou
- Laboratory of Photogrammetry, School of Rural, Surveying and Geoinformatics Engineering, National Technical University of Athens, 15780 Athens, Greece
| | - Charalabos Ioannidis
- Laboratory of Photogrammetry, School of Rural, Surveying and Geoinformatics Engineering, National Technical University of Athens, 15780 Athens, Greece
| | - Sofia Soile
- Laboratory of Photogrammetry, School of Rural, Surveying and Geoinformatics Engineering, National Technical University of Athens, 15780 Athens, Greece
| | - Christos Angelopoulos
- Department of Oral Diagnosis and Radiology, School of Dentistry, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Konstantinos Theodoridis
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Athanasios S Arampatzis
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Andreana N Assimopoulou
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Dimitrios Christofilos
- School of Chemical Engineering & Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Afroditi Kapourani
- Laboratory of Pharmaceutical Technology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Ioannis Pantazos
- Laboratory of Pharmaceutical Technology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Panagiotis Barmpalexis
- Laboratory of Pharmaceutical Technology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Argyro-Maria Boutsi
- Laboratory of Photogrammetry, School of Rural, Surveying and Geoinformatics Engineering, National Technical University of Athens, 15780 Athens, Greece
| | - Chryssy Potsiou
- Laboratory of Photogrammetry, School of Rural, Surveying and Geoinformatics Engineering, National Technical University of Athens, 15780 Athens, Greece
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Theodoridis K, Arampatzis AS, Liasi G, Tsalikis L, Barmpalexis P, Christofilos D, Assimopoulou AN. 3D-Printed Antibacterial Scaffolds for the Regeneration of Alveolar Bone in Severe Periodontitis. Int J Mol Sci 2023; 24:16754. [PMID: 38069075 PMCID: PMC10706713 DOI: 10.3390/ijms242316754] [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] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/20/2023] [Accepted: 11/23/2023] [Indexed: 12/18/2023] Open
Abstract
Current clinical treatment of periodontitis alleviates periodontal symptoms and helps to keep the disease under control for extended periods. Despite this, a significant destruction of the tooth's underlying bone tissue often takes place progressively. Herein, we present a two-way therapeutic approach for local delivery of antibacterial agents and bone tissue regeneration, incorporating ~1% w/w tetracycline hydrochloride (TCH) into a 3D-printed scaffold composed of poly(ε-caprolactone) (PCL). Samples were assessed for their morphological, physicochemical, pharmacokinetic, and antibacterial properties. Furthermore, osteoprecursor cells (MC3T3-E1) were employed to evaluate the osteoinductive potential of the drug-loaded scaffolds. Cell proliferation, viability, and differentiation were determined on all cell-seeded scaffolds. At the end of the culture, PCL-TCH scaffolds promoted abundant collagen organic matrix, demonstrating augmented alkaline phosphatase (ALP) activity and areas of accumulated mineralised bone tissue, despite their belayed cell proliferation. Based on the observed effectiveness of the PCL-TCH scaffolds to inhibit Staphylococcus aureus, these constructs could serve as an alternative bioactive implant that supports bacterial inhibition and favours a 3D microenvironment for bone tissue regeneration in severe periodontitis.
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Affiliation(s)
- Konstantinos Theodoridis
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (K.T.); (A.S.A.); (G.L.)
| | - Athanasios S. Arampatzis
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (K.T.); (A.S.A.); (G.L.)
- Natural Products Research Center of Excellence (NatPro-AUTH), Center for Interdisciplinary Research and Innovation of Aristotle University of Thessaloniki, 57001 Thessaloniki, Greece
| | - Georgia Liasi
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (K.T.); (A.S.A.); (G.L.)
| | - Lazaros Tsalikis
- School of Dentistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
| | - Panagiotis Barmpalexis
- Laboratory of Pharmaceutical Technology, Division of Pharmaceutical Technology, School of Pharmacy, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
| | - Dimitrios Christofilos
- School of Chemical Engineering & Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece;
| | - Andreana N. Assimopoulou
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (K.T.); (A.S.A.); (G.L.)
- Natural Products Research Center of Excellence (NatPro-AUTH), Center for Interdisciplinary Research and Innovation of Aristotle University of Thessaloniki, 57001 Thessaloniki, Greece
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Kermenidou M, Frydas IS, Moschoula E, Kousis D, Christofilos D, Karakitsios S, Sarigiannis D. Quantification and characterization of microplastics in the Thermaic Gulf, in the North Aegean Sea. Sci Total Environ 2023:164299. [PMID: 37211124 DOI: 10.1016/j.scitotenv.2023.164299] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 04/26/2023] [Accepted: 05/16/2023] [Indexed: 05/23/2023]
Abstract
The abundance and distribution of microplastics has largely increased during last years and the respective implications on the environment and human health is an emerging field in research. In addition, recent studies in the enclosed Mediterranean Sea in Spain and Italy have shown an extended occurrence of microplastics (MPs) in different sediments of environmental samples. This study is focused on the quantification and the characterization of MPs in the Thermaic Gulf in northern Greece. Briefly, samples from different environmental compartments such as seawater, local beaches and seven commercially available fish species collected and analyzed. MPs particles extracted and classified by size, shape, colour and polymer type. A total of 28,523 microplastic particles recorded in the surface water samples, with their numbers ranging from 189 to 7714 particles per sample. The mean concentration of MPs recorded on the surface water was 1.9 ± 2 items/m3 or 750,846 ± 838,029 items/km2. Beach sediment sample analysis revealed 14,790 microplastic particles, of which 1825 were large microplastics (LMPs, 1-5 mm) and 12,965 were small microplastics (SMPs, <1 mm). Furthermore, beach sediment samples showed a mean concentration of 733.6 ± 136.6 items/m2, with the concentration of LMPs being 90.5 ± 12.4 items/m2 and the concentration of SMPs being 643 ± 132 items/m2. Concerning fish deposition, microplastics were detected in intestines and mean concentrations per species ranged from 1.3 ± 0.6 to 15.0 ± 1.5 items/individual. The differences in microplastic concentrations between species were statistically significant (p < 0.05) and showed that mesopelagic fish contained the highest concentrations, followed by epipelagic species. The most common size fraction found in the data-set was 1.0-2.5 mm, and polyethylene and polypropylene were the most abundant polymer types recorded. This is the first detailed investigation of MPs in Thermaic Gulf, which raises concerns on their potential negative effects.
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Affiliation(s)
- M Kermenidou
- Environmental Engineering Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; HERACLES Research Centre on the Exposome and Health, Center for Interdisciplinary Research and Innovation, Thessaloniki 54124, Greece
| | - I S Frydas
- Environmental Engineering Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; HERACLES Research Centre on the Exposome and Health, Center for Interdisciplinary Research and Innovation, Thessaloniki 54124, Greece
| | - E Moschoula
- Environmental Engineering Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - D Kousis
- Environmental Engineering Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - D Christofilos
- School of Chemical Engineering & Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - S Karakitsios
- Environmental Engineering Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; HERACLES Research Centre on the Exposome and Health, Center for Interdisciplinary Research and Innovation, Thessaloniki 54124, Greece
| | - D Sarigiannis
- Environmental Engineering Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece; HERACLES Research Centre on the Exposome and Health, Center for Interdisciplinary Research and Innovation, Thessaloniki 54124, Greece; School for Advanced Study (IUSS), Science, Technology and Society Department, Environmental Health Engineering, Piazza della Vittoria 15, Pavia 27100, Italy.
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Kampasakali E, Nakas A, Mertzanidis D, Kokkini S, Assimopoulou AN, Christofilos D. μ-Raman Determination of Essential Oils' Constituents from Distillates and Leaf Glands of Origanum Plants. Molecules 2023; 28:molecules28031221. [PMID: 36770888 PMCID: PMC9920943 DOI: 10.3390/molecules28031221] [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] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/18/2023] [Accepted: 01/20/2023] [Indexed: 01/28/2023] Open
Abstract
A novel, inexpensive and simple experimental setup for collecting μ-Raman spectra of volatile liquids in very small quantities was developed. It takes advantage of capillary forces to detain minute volatile liquid volumes. Spectra of volatile and even scattering or absorbing media can be measured more effectively. The method is used to facilitate the collection of intensity-consistent Raman spectra from a series of reference compounds present in Origanum essential oils, in order to quantify their constituents by multiple linear regression. Wild grown Origanum plants, collected from five different regions in Greece and taxonomically identified as O. onites, O. vulgare subsp. hirtum and O. vulgare subsp. vulgare, were appropriately distilled to acquire their essential oils. Comparison of the Raman results with those from headspace gas chromatography-mass spectrometry (HS GC-MS) confirmed the successful relative quantification of the most abundant essential oil constituents, highlighting the similarities and differences of the three Origanum taxa examined. Finally, it is demonstrated that directly measuring the leaf peltate glandular hairs yields exploitable results to identify the main components of the essential oil they contain, underlining the potential of in situ (field or industry) measurements utilizing microscope-equipped portable Raman spectrometers.
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Affiliation(s)
- Elli Kampasakali
- School of Chemical Engineering & Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
| | - Alexandros Nakas
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center for Interdisciplinary Research and Innovation-Aristotle University of Thessaloniki, 57001 Thessaloniki, Greece
| | - Dimitrios Mertzanidis
- Laboratory of Systematic Botany and Phytogeography, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center for Interdisciplinary Research and Innovation-Aristotle University of Thessaloniki, 57001 Thessaloniki, Greece
| | - Stella Kokkini
- Laboratory of Systematic Botany and Phytogeography, School of Biology, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center for Interdisciplinary Research and Innovation-Aristotle University of Thessaloniki, 57001 Thessaloniki, Greece
| | - Andreana N. Assimopoulou
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center for Interdisciplinary Research and Innovation-Aristotle University of Thessaloniki, 57001 Thessaloniki, Greece
| | - Dimitrios Christofilos
- School of Chemical Engineering & Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Correspondence:
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Arampatzis AS, Giannakoula K, Kontogiannopoulos KN, Theodoridis K, Aggelidou E, Rat A, Kampasakali E, Willems A, Christofilos D, Kritis A, Papageorgiou VP, Tsivintzelis I, Assimopoulou AN. Novel electrospun poly-hydroxybutyrate scaffolds as carriers for the wound healing agents alkannins and shikonins. Regen Biomater 2021; 8:rbab011. [PMID: 34211727 PMCID: PMC8240617 DOI: 10.1093/rb/rbab011] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 02/04/2021] [Accepted: 02/04/2021] [Indexed: 12/31/2022] Open
Abstract
The aim of this study was to investigate the potential of novel electrospun fiber mats loaded with alkannin and shikonin (A/S) derivatives, using as carrier a highly biocompatible, bio-derived, eco-friendly polymer such as poly[(R)-3-hydroxybutyric acid] (PHB). PHB fibers containing a mixture of A/S derivatives at different ratios were successfully fabricated via electrospinning. Αs evidenced by scanning electron microscopy, the fibers formed a bead-free mesh with average diameters from 1.25 to 1.47 μm. Spectroscopic measurements suggest that electrospinning marginally increases the amorphous content of the predominantly crystalline PHB in the fibers, while a significant drug amount lies near the fiber surface for samples of high total A/S content. All scaffolds displayed satisfactory characteristics, with the lower concentrations of A/S mixture-loaded PHB fiber mats achieving higher porosity, water uptake ratios, and entrapment efficiencies. The in vitro dissolution studies revealed that all samples released more than 70% of the encapsulated drug after 72 h. All PHB scaffolds tested by cell viability assay were proven non-toxic for Hs27 fibroblasts, with the 0.15 wt.% sample favoring cell attachment, spreading onto the scaffold surface, as well as cell proliferation. Finally, the antimicrobial activity of PHB meshes loaded with A/S mixture was documented for Staphylococcus epidermidis and S. aureus.
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Affiliation(s)
- Athanasios S Arampatzis
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki (AUTh), Thessaloniki 54124, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center of Interdisciplinary Research and Innovation of Aristotle University of Thessaloniki (CIRI-AUTh), Thessaloniki 57001, Greece
| | - Konstantina Giannakoula
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki (AUTh), Thessaloniki 54124, Greece
| | - Konstantinos N Kontogiannopoulos
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki (AUTh), Thessaloniki 54124, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center of Interdisciplinary Research and Innovation of Aristotle University of Thessaloniki (CIRI-AUTh), Thessaloniki 57001, Greece
| | - Konstantinos Theodoridis
- Department of Physiology and Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki (AUTh), Thessaloniki, Greece
| | - Eleni Aggelidou
- Department of Physiology and Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki (AUTh), Thessaloniki, Greece
| | - Angélique Rat
- Laboratory of Microbiology, Faculty of Sciences, Ghent University, Ghent 9000, Belgium
| | - Elli Kampasakali
- Faculty of Engineering, School of Chemical Engineering and Physics Laboratory, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Anne Willems
- Laboratory of Microbiology, Faculty of Sciences, Ghent University, Ghent 9000, Belgium
| | - Dimitrios Christofilos
- Faculty of Engineering, School of Chemical Engineering and Physics Laboratory, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Aristeidis Kritis
- Department of Physiology and Pharmacology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki (AUTh), Thessaloniki, Greece
| | - Vassilios P Papageorgiou
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki (AUTh), Thessaloniki 54124, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center of Interdisciplinary Research and Innovation of Aristotle University of Thessaloniki (CIRI-AUTh), Thessaloniki 57001, Greece
| | - Ioannis Tsivintzelis
- Physical Chemistry Laboratory, School of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Andreana N Assimopoulou
- Laboratory of Organic Chemistry, School of Chemical Engineering, Aristotle University of Thessaloniki (AUTh), Thessaloniki 54124, Greece
- Natural Products Research Centre of Excellence (NatPro-AUTh), Center of Interdisciplinary Research and Innovation of Aristotle University of Thessaloniki (CIRI-AUTh), Thessaloniki 57001, Greece
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Affiliation(s)
- Anna Marinopoulou
- Department of Food Science and Technology, Central Research Laboratory for the Physical and Chemical Testing of Foods International Hellenic University Alexandrian Campus Thessaloniki 57400 Greece
| | - Dimitrios Christofilos
- School of Chemical Engineering & Physics Laboratory, Faculty of Engineering Aristotle University of Thessaloniki Thessaloniki 54124 Greece
| | - John Arvanitidis
- Physics Department Aristotle University of Thessaloniki Thessaloniki 54124 Greece
| | - Stylianos N. Raphaelides
- Department of Food Science and Technology, Central Research Laboratory for the Physical and Chemical Testing of Foods International Hellenic University Alexandrian Campus Thessaloniki 57400 Greece
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Gavriil V, Chatzichristidi M, Christofilos D, Kourouklis GA, Kollia Z, Bakalis E, Cefalas AC, Sarantopoulou E. Entropy and Random Walk Trails Water Confinement and Non-Thermal Equilibrium in Photon-Induced Nanocavities. Nanomaterials (Basel) 2020; 10:E1101. [PMID: 32498312 PMCID: PMC7353189 DOI: 10.3390/nano10061101] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/18/2020] [Accepted: 05/22/2020] [Indexed: 01/18/2023]
Abstract
Molecules near surfaces are regularly trapped in small cavitations. Molecular confinement, especially water confinement, shows intriguing and unexpected behavior including surface entropy adjustment; nevertheless, observations of entropic variation during molecular confinement are scarce. An experimental assessment of the correlation between surface strain and entropy during molecular confinement in tiny crevices is difficult because strain variances fall in the nanometer scale. In this work, entropic variations during water confinement in 2D nano/micro cavitations were observed. Experimental results and random walk simulations of water molecules inside different size nanocavitations show that the mean escaping time of molecular water from nanocavities largely deviates from the mean collision time of water molecules near surfaces, crafted by 157 nm vacuum ultraviolet laser light on polyacrylamide matrixes. The mean escape time distribution of a few molecules indicates a non-thermal equilibrium state inside the cavity. The time differentiation inside and outside nanocavities reveals an additional state of ordered arrangements between nanocavities and molecular water ensembles of fixed molecular length near the surface. The configured number of microstates correctly counts for the experimental surface entropy deviation during molecular water confinement. The methodology has the potential to identify confined water molecules in nanocavities with life science importance.
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Affiliation(s)
- Vassilios Gavriil
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece; (V.G.); (Z.K.); (E.B.); (A.-C.C.)
- School of Chemical Engineering and Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece; (D.C.); (G.A.K.)
| | - Margarita Chatzichristidi
- Department of Chemistry, Laboratory of Industrial Chemistry, Panepistimiopolis Zografou, National and Kapodistrian University of Athens, 15771 Athens, Greece;
| | - Dimitrios Christofilos
- School of Chemical Engineering and Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece; (D.C.); (G.A.K.)
| | - Gerasimos A. Kourouklis
- School of Chemical Engineering and Physics Laboratory, Faculty of Engineering, Aristotle University of Thessaloniki, University Campus, 54124 Thessaloniki, Greece; (D.C.); (G.A.K.)
| | - Zoe Kollia
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece; (V.G.); (Z.K.); (E.B.); (A.-C.C.)
| | - Evangelos Bakalis
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece; (V.G.); (Z.K.); (E.B.); (A.-C.C.)
- Dipartimento di Chimica “G. Giamician” University di Bologna, Via F. Selmi 2, 40126 Bologna, Italy
| | - Alkiviadis-Constantinos Cefalas
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece; (V.G.); (Z.K.); (E.B.); (A.-C.C.)
| | - Evangelia Sarantopoulou
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, 11635 Athens, Greece; (V.G.); (Z.K.); (E.B.); (A.-C.C.)
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Marinopoulou A, Christofilos D, Arvanitidis J, Raphaelides SN. Study of Molecular Inclusion Complex Formation of Amylose With Indomethacin. STARCH-STARKE 2019. [DOI: 10.1002/star.201800295] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Anna Marinopoulou
- Central Research Laboratory for the Physical and Chemical Testing of FoodsDepartment of Food TechnologyATEI of ThessalonikiP.O. Box 141, 57400 ThessalonikiGreece
| | - Dimitrios Christofilos
- School of Chemical EngineeringAristotle University of Thessaloniki54124 ThessalonikiGreece
| | - John Arvanitidis
- Physics DepartmentAristotle University of Thessaloniki54124 ThessalonikiGreece
| | - Stylianos N. Raphaelides
- Central Research Laboratory for the Physical and Chemical Testing of FoodsDepartment of Food TechnologyATEI of ThessalonikiP.O. Box 141, 57400 ThessalonikiGreece
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Paschou AM, Katsikini M, Christofilos D, Arvanitidis J, Ves S. High pressure Raman study of type-I collagen. FEBS J 2018; 285:2641-2653. [PMID: 29775998 DOI: 10.1111/febs.14506] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Revised: 04/24/2018] [Accepted: 05/14/2018] [Indexed: 12/28/2022]
Abstract
The high pressure response of type-I collagen from bovine Achilles tendon is investigated with micro-Raman spectroscopy. Fluorinert™ and methanol-ethanol mixtures were used as pressure transmitting media (PTM) in a diamond anvil cell. The Raman spectrum of collagen is dominated by three bands centred at approximately 1450, 1660 and 2930 cm-1 , attributed to C-H deformation, C=O stretching of the peptide bond (amide-I band) and C-H stretching modes respectively. Upon pressure increase, using Fluorinert™ as PTM, a shift towards higher frequencies of the C-H stretching and deformation peaks is observed. Contrary, the amide-I band peaks are shifted to lower frequencies with moderate pressure slopes. On the other hand, when using the alcohol mixture as PTM, the amide-I band exhibits more pronounced C=O bond softening, deduced from the shift to lower frequencies, suggesting a strengthening of the hydrogen bonds between glycine and proline residues of different collagen chains due to the presence of the polar alcohol molecules. Furthermore, some of the peaks exhibit abrupt changes in their pressure slopes at approximately 2 GPa, implying a variation in the compressibility of the collagen fibres. This could be attributed to a pitch change from 10/3 to 7/2, sliding of the tropocollagen molecules, twisting variation at the molecular level and/or elimination of the D-gaps induced by kink compression. All spectral changes are reversible upon pressure release, which indicates that denaturation has not taken place. Finally, a minor lipid phase contamination was detected in some sample spots. Its pressure response is also monitored.
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Affiliation(s)
- Amalia Maria Paschou
- Department of Solid State Physics, School of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Maria Katsikini
- Department of Solid State Physics, School of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Dimitrios Christofilos
- Department of Technologies, School of Chemical Engineering, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - John Arvanitidis
- Department of Solid State Physics, School of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Sotirios Ves
- Department of Solid State Physics, School of Physics, Aristotle University of Thessaloniki, Thessaloniki, Greece
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Beketova A, Poulakis N, Bakopoulou A, Zorba T, Papadopoulou L, Christofilos D, Kantiranis N, Zachariadis GA, Kontonasaki E, Kourouklis GA, Paraskevopoulos KM, Koidis P. Inducing bioactivity of dental ceramic/bioactive glass composites by Nd:YAG laser. Dent Mater 2016; 32:e284-e296. [PMID: 27682895 DOI: 10.1016/j.dental.2016.09.029] [Citation(s) in RCA: 8] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Revised: 07/01/2016] [Accepted: 09/03/2016] [Indexed: 11/28/2022]
Abstract
OBJECTIVES Aims of this study were to investigate the optimal conditions of laser irradiation of a novel Bioactive Glass/Dental Ceramic-BP67 composite for acceleration of hydroxyapatite-HA formation and to assess cellular responses on the precipitated HA region. METHODS BP67 (Bioactive Glass: 33.3%, Dental Ceramic: 66.7%) was fabricated by the sol-gel method. A laser assisted biomimetic-LAB process was applied to BP67 sintered specimens immersed in 1.5-times concentrated simulated body fluid-1.5×-SBF. The effect of various energy densities of pulsed nanosecond Nd-YAG (1064nm) laser and irradiation exposure times (30min, 1 and 3h) were evaluated for HA precipitation. The HA film was characterized by FTIR, XRD, SEM and micro Raman techniques. ICP-AES was used for revealing changes in chemical composition of the 1.5×-SBF during irradiation. Cell viability and morphological characteristics of periodontal ligament fibroblasts-PDLFs, human gingival fibroblasts-HGFs and SAOS-2 osteoblasts on the HA surface were evaluated by MTT assays and SEM. RESULTS At optimal energy fluence of 1.52J/cm2 and irradiation time for 3h followed by immersion in 1.5×-SBF at 60°C, a dense HA layer was formed on laser-irradiated BP67 within 7 days. The resulting HA film was tightly bonded to the underlying substrate and had mineral composition similar to cementum. MTT assay showed a consistent reduction of cell proliferation on the HA layer in comparison to conventional control ceramic and BP67 for all 3 cell lines studied. SIGNIFICANCE These findings suggest LAB is an effective method for acceleration of HA formation on materials with low bioactivity, while cellular responses need further investigation.
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Affiliation(s)
- Anastasia Beketova
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - Nikolaos Poulakis
- Department of Electrical Engineering, Technological Educational Institute of Western Macedonia, Koila, 50100 Kozani, Greece
| | - Athina Bakopoulou
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - Triantafillia Zorba
- Physics Department, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - Lambrini Papadopoulou
- School of Geology, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - Dimitrios Christofilos
- Department of Chemical Engineering, School of Engineering, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - Nikolaos Kantiranis
- School of Geology, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - George A Zachariadis
- Department of Chemistry, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - Eleana Kontonasaki
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | - Gerasimos A Kourouklis
- Department of Chemical Engineering, School of Engineering, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece
| | | | - Petros Koidis
- Department of Fixed Prosthesis and Implant Prosthodontics, School of Dentistry, Aristotle University of Thessaloniki, Thessaloniki GR-54124, Greece.
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Meletov K, Arvanitidis J, Christofilos D, Kourouklis G, Davydov V. Raman study of the temperature-induced decomposition of the fullerene dimers C120. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2016.05.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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Spyropoulos-Antonakakis N, Sarantopoulou E, Drazic G, Kollia Z, Christofilos D, Kourouklis G, Palles D, Cefalas AC. Charge transport mechanisms and memory effects in amorphous TaNx thin films. Nanoscale Res Lett 2013; 8:432. [PMID: 24134740 PMCID: PMC4016540 DOI: 10.1186/1556-276x-8-432] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 08/28/2013] [Indexed: 06/02/2023]
Abstract
Amorphous semiconducting materials have unique electrical properties that may be beneficial in nanoelectronics, such as low leakage current, charge memory effects, and hysteresis functionality. However, electrical characteristics between different or neighboring regions in the same amorphous nanostructure may differ greatly. In this work, the bulk and surface local charge carrier transport properties of a-TaNx amorphous thin films deposited in two different substrates are investigated by conductive atomic force microscopy. The nitride films are grown either on Au (100) or Si [100] substrates by pulsed laser deposition at 157 nm in nitrogen environment. For the a-TaNx films deposited on Au, it is found that they display a negligible leakage current until a high bias voltage is reached. On the contrary, a much lower threshold voltage for the leakage current and a lower total resistance is observed for the a-TaNx film deposited on the Si substrate. Furthermore, I-V characteristics of the a-TaNx film deposited on Au show significant hysteresis effects for both polarities of bias voltage, while for the film deposited on Si hysteresis, effects appear only for positive bias voltage, suggesting that with the usage of the appropriate substrate, the a-TaNx nanodomains may have potential use as charge memory devices.
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Affiliation(s)
- Nikolaos Spyropoulos-Antonakakis
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635, Greece
| | - Evangelia Sarantopoulou
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635, Greece
| | - Goran Drazic
- Laboratory for materials electrochemistry, National Institute of Chemistry, Hajdrihova 19, Ljubljana 1000, Slovenia
| | - Zoe Kollia
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635, Greece
| | - Dimitrios Christofilos
- Physics Division, School of Technology, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Gerasimos Kourouklis
- Physics Division, School of Technology, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Dimitrios Palles
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635, Greece
| | - Alkiviadis Constantinos Cefalas
- National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 48 Vassileos Constantinou Avenue, Athens 11635, Greece
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13
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Chrissopoulou K, Andrikopoulos KS, Fotiadou S, Bollas S, Karageorgaki C, Christofilos D, Voyiatzis GA, Anastasiadis SH. Crystallinity and Chain Conformation in PEO/Layered Silicate Nanocomposites. Macromolecules 2011. [DOI: 10.1021/ma201711r] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- K. Chrissopoulou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece
| | - K. S. Andrikopoulos
- Physics Division, School of Technology, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
| | - S. Fotiadou
- Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece
- Department of Chemical Engineering, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
| | - S. Bollas
- Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece
| | - C. Karageorgaki
- Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece
- Department of Chemical Engineering, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
| | - D. Christofilos
- Physics Division, School of Technology, Aristotle University of Thessaloniki, 541 24 Thessaloniki, Greece
| | - G. A. Voyiatzis
- Institute of Chemical Engineering & High Temperature Chemical Processes, Foundation for Research and Technology - Hellas, P.O. Box 1414, 265 04 Patras, Greece
| | - S. H. Anastasiadis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas, P.O. Box 1527, 711 10 Heraklion Crete, Greece
- Department of Chemistry, University of Crete, P.O. Box 2208, 710 03 Heraklion Crete, Greece
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Baida H, Mongin D, Christofilos D, Bachelier G, Crut A, Maioli P, Del Fatti N, Vallée F. Ultrafast nonlinear optical response of a single gold nanorod near its surface plasmon resonance. Phys Rev Lett 2011; 107:057402. [PMID: 21867097 DOI: 10.1103/physrevlett.107.057402] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Indexed: 05/27/2023]
Abstract
The ultrafast optical nonlinearity of an optically characterized single gold nanorod is investigated around its surface plasmon resonance, by combining a far-field spatial modulation technique with a high sensitivity pump-probe setup. The spectrally and temporally dependent response is quantitatively interpreted in terms of the bulklike optical nonlinearity enhanced by the plasmonic effect. The plasmon resonance dynamics is shown to be mostly governed by nonequilibrium electron and phonon processes. Their contributions to the nonlinear optical response of a single metal nano-object are elucidated, and the latter is connected to the nonlinearities of ensembles.
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Affiliation(s)
- H Baida
- Université Lyon 1, CNRS, LASIM, 43 Boulevard du 11 Novembre, 69622 Villeurbanne cedex, France
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15
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Tsioptsias C, Paraskevopoulos M, Christofilos D, Andrieux P, Panayiotou C. Polymeric hydrogels and supercritical fluids: The mechanism of hydrogel foaming. POLYMER 2011. [DOI: 10.1016/j.polymer.2011.04.043] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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16
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Arvanitidis J, Christofilos D, Kourouklis GA, Paloumpi A, Papagelis K, Ves S, Iwasa Y, Prassides K. Raman spectroscopic study of the rare-earth fullerides Eu6-xSrxC60. Nanoscale 2011; 3:2490-2493. [PMID: 21359319 DOI: 10.1039/c0nr00921k] [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] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We present Raman spectroscopic studies of the isostructural and isoelectronic Eu(6-x)Sr(x)C(60) (x = 0, 3, 5, 6) and Ba(6)C(60) compounds. The Raman spectra of the Eu-based fullerides show dramatic changes compared to the pure alkaline-earth systems, including significant broadening, splitting and frequency shifts of the fivefold degenerate H(g) intramolecular modes of C(60). Moreover, the A(g)(2) mode exhibits an even larger downshift and a remarkable broadening. These findings are consistent with distortions of the C(60) molecular cages and a considerable electron-phonon coupling strength-strongly enhanced in the Eu containing systems-originating from the strong orbital hybridization between the metal atom and the C(60) molecule.
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Affiliation(s)
- J Arvanitidis
- Department of Applied Sciences, Technological Educational Institute of Thessaloniki, 57400, Sindos, Greece.
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17
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Baida H, Billaud P, Marhaba S, Christofilos D, Cottancin E, Crut A, Lermé J, Maioli P, Pellarin M, Broyer M, Del Fatti N, Vallée F, Sánchez-Iglesias A, Pastoriza-Santos I, Liz-Marzán LM. Quantitative determination of the size dependence of surface plasmon resonance damping in single Ag@SiO(2) nanoparticles. Nano Lett 2009; 9:3463-9. [PMID: 19719148 DOI: 10.1021/nl901672b] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
The optical extinction spectra of single silver nanoparticles coated with a silica shell were investigated in the size range 10-50 nm. Measurements were performed using the spatial modulation spectroscopy technique which permits independent determination of both the size of the metal nanoparticle under study and the width of its localized surface plasmon resonance (LSPR). These parameters can thus be directly correlated at a single particle level for the first time. The results show a linear increase of the width of the LSPR with the inverse diameter in the small size regime (less than 25 nm). For these nanoparticles of well-controlled environment, this can be ascribed to quantum confinement of electrons or, classically, to increase of the electron surface scattering processes. The impact of this effect was measured quantitatively and compared to the predictions by theoretical models.
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Affiliation(s)
- H Baida
- Universite Lyon 1, CNRS, LASIM, 43 bd du 11 novembre 1918, 69622 Villeurbanne cedex, France
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18
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Meletov K, Krestinin A, Arvanitidis J, Christofilos D, Kourouklis G. Temperature effects in the Raman spectra of bundled single-wall carbon nanotubes. Chem Phys Lett 2009. [DOI: 10.1016/j.cplett.2009.07.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Meletov K, Maksimov A, Tartakovskii I, Bashkin I, Shestakov V, Krestinin A, Shulga Y, Andrikopoulos K, Arvanitidis J, Christofilos D, Kourouklis G. Raman study of the high-pressure hydrogenated single-wall carbon nanotubes: In search of chemically bonded and adsorbed molecular hydrogen. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2006.11.072] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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20
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Meletov K, Davydov V, Rakhmanina A, Agafonov V, Arvanitidis J, Christofilos D, Andrikopoulos K, Kourouklis G. Influence of pressure on the photopolymerization rate of the linear orthorhombic polymer of C60. Chem Phys Lett 2006. [DOI: 10.1016/j.cplett.2006.07.057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Arbouet A, Christofilos D, Del Fatti N, Vallée F, Huntzinger JR, Arnaud L, Billaud P, Broyer M. Direct measurement of the single-metal-cluster optical absorption. Phys Rev Lett 2004; 93:127401. [PMID: 15447305 DOI: 10.1103/physrevlett.93.127401] [Citation(s) in RCA: 59] [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] [Received: 01/24/2004] [Indexed: 05/21/2023]
Abstract
The absorption of a single isolated metal cluster is directly measured using a novel far-field optical technique based on modulation of its position. Single gold nanoparticles with average diameters down to 5 nm, dispersed on a transparent substrate, are optically detected and their absolute absorption cross section determined.
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Affiliation(s)
- A Arbouet
- Centre de Physique Moléculaire Optique et Hertzienne, CNRS, 351 cours de la Libération, 33405 Talence, France
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22
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Arbouet A, Voisin C, Christofilos D, Langot P, Fatti ND, Vallée F, Lermé J, Celep G, Cottancin E, Gaudry M, Pellarin M, Broyer M, Maillard M, Pileni MP, Treguer M. Electron-phonon scattering in metal clusters. Phys Rev Lett 2003; 90:177401. [PMID: 12786103 DOI: 10.1103/physrevlett.90.177401] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2002] [Indexed: 05/24/2023]
Abstract
Electron-lattice energy exchanges are investigated in gold and silver nanoparticles with sizes ranging from 30 to 2.2 nm embedded in different environments. Femtosecond pump-probe experiments performed in the low-perturbation regime demonstrate a strong increase of the intrinsic electron-phonon interaction for nanoparticles smaller than 10 nm due to a confinement effect.
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Affiliation(s)
- A Arbouet
- Centre de Physique Moléculaire Optique et Hertzienne, CNRS and Université Bordeaux I, 351 cours de la Libération, 33405 Talence, France
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Voisin C, Christofilos D, Vallee F, Prevel B, Cottancin E, Lerme J, Pellarin M, Broyer M. Size-dependent electron-electron interactions in metal nanoparticles. Phys Rev Lett 2000; 85:2200-2203. [PMID: 10970497 DOI: 10.1103/physrevlett.85.2200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2000] [Indexed: 05/23/2023]
Abstract
The internal thermalization dynamics of the conduction electrons is investigated in silver nanoparticles with radius ranging from 13 to 1.6 nm using a femtosecond IR pump-UV probe absorption saturation technique. A sharp increase of the electron energy exchange rate is demonstrated for nanoparticles smaller than 5 nm. The results are consistent with electron-electron scattering acceleration due to surface induced reduction of the Coulomb interaction screening by the conduction and core electrons.
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Affiliation(s)
- C Voisin
- Laboratoire d'Optique Quantique du CNRS, Ecole Polytechnique, 91128 Palaiseau cedex, France
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Affiliation(s)
- N. Del Fatti
- Laboratoire d'Optique Quantique du CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex, France
| | - C. Voisin
- Laboratoire d'Optique Quantique du CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex, France
| | - D. Christofilos
- Laboratoire d'Optique Quantique du CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex, France
| | - F. Vallée
- Laboratoire d'Optique Quantique du CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex, France
| | - C. Flytzanis
- Laboratoire d'Optique Quantique du CNRS, Ecole Polytechnique, 91128 Palaiseau Cedex, France
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Langot P, Christofilos D, Tommasi R, Vallée F. Femtosecond investigation of the hot-phonon effect in GaAs at room temperature. Phys Rev B Condens Matter 1996; 54:14487-14493. [PMID: 9985453 DOI: 10.1103/physrevb.54.14487] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Meletov KP, Christofilos D, Ves S, Kourouklis GA. Pressure-induced orientational ordering in C60 single crystals studied by Raman spectroscopy. Phys Rev B Condens Matter 1995; 52:10090-10096. [PMID: 9980056 DOI: 10.1103/physrevb.52.10090] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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