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Moud AA. Fluorescence Recovery after Photobleaching in Colloidal Science: Introduction and Application. ACS Biomater Sci Eng 2022; 8:1028-1048. [PMID: 35201752 DOI: 10.1021/acsbiomaterials.1c01422] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
FRAP (fluorescence recovery after photo bleaching) is a method for determining diffusion in material science. In industrial applications such as medications, foods, Medtech, hygiene, and textiles, the diffusion process has a substantial influence on the overall qualities of goods. All these complex and heterogeneous systems have diffusion-based processes at the local level. FRAP is a fluorescence-based approach for detecting diffusion; in this method, a high-intensity laser is made for a brief period and then applied to the samples, bleaching the fluorescent chemical inside the region, which is subsequently filled up by natural diffusion. This brief Review will focus on the existing research on employing FRAP to measure colloidal system heterogeneity and explore diffusion into complicated structures. This description of FRAP will be followed by a discussion of how FRAP is intended to be used in colloidal science. When constructing the current Review, the most recent publications were reviewed for this assessment. Because of the large number of FRAP articles in colloidal research, there is currently a dearth of knowledge regarding the growth of FRAP's significance to colloidal science. Colloids make up only 2% of FRAP papers, according to ISI Web of Knowledge.
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Affiliation(s)
- Aref Abbasi Moud
- Department of Chemical and Biological Engineering, The University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
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2
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Surface modification, adsorption behavior, and optical properties of α-Fe2O3@SiO2/Au core-shell ellipsoids. Colloids Surf A Physicochem Eng Asp 2021. [DOI: 10.1016/j.colsurfa.2021.126888] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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3
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Meijer JM, Rossi L. Preparation, properties, and applications of magnetic hematite microparticles. SOFT MATTER 2021; 17:2354-2368. [PMID: 33514989 DOI: 10.1039/d0sm01977a] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Hematite microparticles are becoming increasingly important components in the soft matter field. The remarkable combination of magnetic and photocatalytic properties that characterize them, coupled with the variety of uniform and monodisperse shapes that they can be synthesized in, makes them a one of a kind colloidal model system. Thanks to these properties, hematite microparticles have been recently applied in several important soft matter applications, spanning from novel colloidal building blocks for self-assembly to necessary tools to investigate and understand fundamental problems. In this review article we provide a detailed overview of the traditional methods available for the preparation of hematite microparticles of different shapes, devoting special attention on some of the most common hiccups that could hider a successful synthesis. We furthermore review the particles' most important physico-chemical properties and their most relevant applications in the soft matter field.
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Affiliation(s)
- J M Meijer
- Department of Applied Physics, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
| | - L Rossi
- Department of Chemical Engineering, Delft University of Technology, 2629 HZ Delft, The Netherlands.
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4
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Rosenberg M, Gregorin Ž, Boštjančič PH, Sebastián N, Lisjak D, Kantorovich SS, Mertelj A, Sánchez PA. The influence of polydispersity on the structural properties of the isotropic phase of magnetic nanoplatelets. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.113293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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5
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Shape anisotropic colloidal particle fabrication using 2-photon polymerization. J Colloid Interface Sci 2019; 564:43-51. [PMID: 31901833 DOI: 10.1016/j.jcis.2019.12.035] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 12/07/2019] [Accepted: 12/08/2019] [Indexed: 02/08/2023]
Abstract
HYPOTHESIS Our ability to dictate the colloid geometry is intimately related to self-assembly. The synthesis of anisotropic colloidal particles is currently dominated by wet chemistry and lithographic techniques. The wet chemical synthesis offers limited particle geometries at bulk quantities. Lithographic techniques, on the other hand, provide precise control over the particle shape, although at lower yields. In this respect, two-photon polymerization (2PP)1 has attracted growing attention due to its ability to automatically fabricate complex micro/nano structures with high resolution. EXPERIMENTS We manufacture precisely designed colloids with sizes ranging from 1 µm to 10 µm with 2PP and optimize the process parameters for each dimension. Moreover, we study the shape dependent Brownian motion of these particles with video microscopy and estimate their diffusion coefficients. FINDINGS We observe that increasing the geometrical anisotropy leads to a pronounced deviation from the analytically predicted diffusion coefficient for disks with a given aspect ratio. The deviation is attributed to stronger hydrodynamic coupling with increasing anisotropy. We demonstrate, for the first time, 2PP manufacturing of colloids with tailored geometry. This study opens synthesis of colloidal building blocks to a broader audience with limited access to cleanrooms or wet-chemistry know-how.
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6
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Gomez-Flores A, Bradford SA, Wu L, Kim H. Interaction energies for hollow and solid cylinders: Role of aspect ratio and particle orientation. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.123781] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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7
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Roca AG, Gutiérrez L, Gavilán H, Fortes Brollo ME, Veintemillas-Verdaguer S, Morales MDP. Design strategies for shape-controlled magnetic iron oxide nanoparticles. Adv Drug Deliv Rev 2019; 138:68-104. [PMID: 30553951 DOI: 10.1016/j.addr.2018.12.008] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 11/20/2018] [Accepted: 12/11/2018] [Indexed: 01/01/2023]
Abstract
Ferrimagnetic iron oxide nanoparticles (magnetite or maghemite) have been the subject of an intense research, not only for fundamental research but also for their potentiality in a widespread number of practical applications. Most of these studies were focused on nanoparticles with spherical morphology but recently there is an emerging interest on anisometric nanoparticles. This review is focused on the synthesis routes for the production of uniform anisometric magnetite/maghemite nanoparticles with different morphologies like cubes, rods, disks, flowers and many others, such as hollow spheres, worms, stars or tetrapods. We critically analyzed those procedures, detected the key parameters governing the production of these nanoparticles with particular emphasis in the role of the ligands in the final nanoparticle morphology. The main structural and magnetic features as well as the nanotoxicity as a function of the nanoparticle morphology are also described. Finally, the impact of each morphology on the different biomedical applications (hyperthermia, magnetic resonance imaging and drug delivery) are analysed in detail. We would like to dedicate this work to Professor Carlos J. Serna, Instituto de Ciencia de Materiales de Madrid, ICMM/CSIC, for his outstanding contribution in the field of monodispersed colloids and iron oxide nanoparticles. We would like to express our gratitude for all these years of support and inspiration on the occasion of his retirement.
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Affiliation(s)
- Alejandro G Roca
- Dept. Energía, Medio Ambiente y Salud, Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049 Madrid, Spain; Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, E-08193 Barcelona, Spain.
| | - Lucía Gutiérrez
- Dept. Energía, Medio Ambiente y Salud, Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049 Madrid, Spain; Dept. Química Analítica, Instituto de Nanociencia de Aragón, Universidad de Zaragoza and CIBER-BBN, E-50018 Zaragoza, Spain.
| | - Helena Gavilán
- Dept. Energía, Medio Ambiente y Salud, Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049 Madrid, Spain.
| | - Maria Eugênia Fortes Brollo
- Dept. Energía, Medio Ambiente y Salud, Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049 Madrid, Spain.
| | - Sabino Veintemillas-Verdaguer
- Dept. Energía, Medio Ambiente y Salud, Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049 Madrid, Spain.
| | - María Del Puerto Morales
- Dept. Energía, Medio Ambiente y Salud, Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, E-28049 Madrid, Spain.
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8
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Zhao K, Mason TG. Assembly of colloidal particles in solution. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:126601. [PMID: 29978830 DOI: 10.1088/1361-6633/aad1a7] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Advances in both top-down and bottom-up syntheses of a wide variety of complex colloidal building blocks and also in methods of controlling their assembly in solution have led to new and interesting forms of highly controlled soft matter. In particular, top-down lithographic methods of producing monodisperse colloids now provide precise human-designed control over their sub-particle features, opening up a wide range of new possibilities for assembly structures that had been previously limited by the range of shapes available through bottom-up methods. Moreover, an increasing level of control over anisotropic interactions between these colloidal building blocks, which can be tailored through local geometries of sub-particle features as well as site-specific surface modifications, is giving rise to new demonstrations of massively parallel off-chip self-assembly of specific target structures with low defect rates. In particular, new experimental realizations of hierarchical self-assembly and control over the chiral purity of resulting assembly structures have been achieved. Increasingly, shape-dependent, shape-complementary, and roughness-controlled depletion attractions between non-spherical colloids are being used in novel ways to create assemblies that go far beyond early examples, such as fractal clusters formed by diffusion-limited and reaction-limited aggregation of spheres. As self-assembly methods have progressed, a wide variety of advanced directed assembly methods have also been developed; approaches based on microfluidic control and applying structured electromagnetic fields are particularly promising.
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Affiliation(s)
- Kun Zhao
- Key Laboratory of Systems Bioengineering (Ministry of Education), School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, People's Republic of China
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9
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Roller J, Pfleiderer P, Meijer JM, Zumbusch A. Detection and tracking of anisotropic core-shell colloids. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:395903. [PMID: 30141415 DOI: 10.1088/1361-648x/aadcbf] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Optical microscopy techniques with three dimensional (3D) resolution are powerful tools for the real-space imaging of the structure and dynamics of colloidal systems. While real-space imaging of spherical particles is well established, the observation of shape anisotropic particles has only recently met a lot of interest. Apart from translation, shape anisotropic particles also possess additional rotational degrees of freedom. In this manuscript, we introduce a novel technique to find the position and the orientation of anisotropic particles in 3D. It is based on an algorithm which is applicable to core-shell particles consisting of a spherical core and a shell with arbitrary shape. We demonstrate the performance of this algorithm using PMMA/PMMA (polymethyl methacrylate) core-shell ellipsoids. The algorithm is tested on artificial images and on experimental data. The correct identification of particle positions with subpixel accuracy and of their orientations with high angular precision in dilute and dense systems is shown. In addition, we developed an advanced particle tracking algorithm that takes both translational and rotational movements of the anisotropic particles into account. We show that our 3D detection and tracking technique is suitable for the accurate and reliable detection of large and dense colloidal systems containing several thousands of particles.
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Affiliation(s)
- J Roller
- Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457 Konstanz, Germany
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10
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Liu B, Wu Y, Zhao S. Anisotropic Colloids: From Non-Templated to Patchy Templated Synthesis. Chemistry 2018; 24:10562-10570. [PMID: 29469224 DOI: 10.1002/chem.201705960] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Indexed: 11/09/2022]
Abstract
Self-assembly of colloidal particles is an important and challenging way to generate novel colloidal superstructures for new materials. Recent progress on syntheses of anisotropic colloids highlights opportunities for such self-assembly, particularly in defining new non-cubic superstructures. Both non-templated and templated synthesis play an important role in preparing anisotropic colloidal particles. In this article, we briefly summarize recent progress in anisotropic colloids by non-templated and conventional templated synthesis, and introduce a conceptual strategy of "patchy templated synthesis" that differs from the conventional approach. We illustrate this strategy with recent examples emanating from colloidal rings, and discuss the future opportunities with this strategy for the synthesis of other anisotropic colloids.
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Affiliation(s)
- Bing Liu
- State Key Laboratory of Polymer Physics and Chemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Yuanyuan Wu
- State Key Laboratory of Polymer Physics and Chemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
| | - Shuping Zhao
- State Key Laboratory of Polymer Physics and Chemistry, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, P. R. China
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11
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Yu B, Cong H, Peng Q, Gu C, Tang Q, Xu X, Tian C, Zhai F. Current status and future developments in preparation and application of nonspherical polymer particles. Adv Colloid Interface Sci 2018; 256:126-151. [PMID: 29705026 DOI: 10.1016/j.cis.2018.04.010] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 03/30/2018] [Accepted: 04/14/2018] [Indexed: 11/16/2022]
Abstract
Nonspherical polymer particles (NPPs) are nano/micro-particulates of macromolecules that are anisotropic in shape, and can be designed anisotropic in chemistry. Due to shape and surface anisotropies, NPPs bear many unique structures and fascinating properties which are distinctly different from those of spherical polymer particles (SPPs). In recent years, the research on NPPs has surprisingly blossomed in recent years, and many practical materials based on NPPs with potential applications in photonic device, material science and biomedical engineering have been generated. In this review, we give a systematic, balanced and comprehensive summary of the main aspects of NPPs related to their preparation and application, and propose perspectives for the future developments of NPPs.
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Affiliation(s)
- Bing Yu
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China; Laboratory for New Fiber Materials and Modern Textile, Growing Base for State Key Laboratory, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Hailin Cong
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China; Laboratory for New Fiber Materials and Modern Textile, Growing Base for State Key Laboratory, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, China.
| | - Qiaohong Peng
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China
| | - Chuantao Gu
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China
| | - Qi Tang
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China
| | - Xiaodan Xu
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China
| | - Chao Tian
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China
| | - Feng Zhai
- Institute of Biomedical Materials and Engineering, College of Chemistry and Chemical Engineering, Qingdao University, Qingdao 266071, China
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12
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Abstract
Increasing significance is being placed on the synthesis of smart colloidal particles, since the route to various meta-materials has been outlined through their bottom-up self-assembly. Unfortunately, making particles with well-defined shape and surface chemistry often requires considerable effort and time, and as such, they are available only in restrictive yields. Here we report a synthetic methodology, which we refer to as mix-and-melt reactions (MMR), that allows for rapid prototyping and mass production of anisotropic core-shell colloids. MMR take advantage of the synergistic properties between common colloidal suspensions by aggregating then reconfiguring polystyrene shell particles onto core particle substrates. By systematically exchanging cores and shells, the resultant core-shell particle's properties are manipulated in a modular fashion. The influence of the constituent particles' size ratio is extensively explored, which is shown to tune shell thickness, change the aspect ratio of shells on anisotropic cores, and access specific shapes such as tetrahedra. Beyond particle shape, mixed shell systems are utilized to create regular surface patches. Surface Evolver simulations are used to demonstrate how randomly packed clusters melt into regular shapes via a shell compartmentalization mechanism.
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Affiliation(s)
- Theodore Hueckel
- Molecular Design Institute, Department of Chemistry , New York University , 29 Washington Place , New York , New York 10003 , United States
| | - Stefano Sacanna
- Molecular Design Institute, Department of Chemistry , New York University , 29 Washington Place , New York , New York 10003 , United States
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13
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Gong Z, Hueckel T, Yi GR, Sacanna S. Patchy particles made by colloidal fusion. Nature 2017; 550:234-238. [DOI: 10.1038/nature23901] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 08/02/2017] [Indexed: 12/26/2022]
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14
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Maleki A, Kettiger H, Schoubben A, Rosenholm JM, Ambrogi V, Hamidi M. Mesoporous silica materials: From physico-chemical properties to enhanced dissolution of poorly water-soluble drugs. J Control Release 2017; 262:329-347. [PMID: 28778479 DOI: 10.1016/j.jconrel.2017.07.047] [Citation(s) in RCA: 153] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 06/24/2017] [Accepted: 07/31/2017] [Indexed: 12/20/2022]
Abstract
New approaches in pharmaceutical chemistry have resulted in more complex drug molecules in the quest to achieve higher affinity to their targets. However, these 'highly active' drugs can also suffer from poor water solubility. Hence, poorly water soluble drugs became a major challenge in drug formulation, and this problem is increasing, as currently about 40 of the marketed drugs and 90% of drug candidates are classified as poorly water soluble. Various approaches exist to circumvent poor water solubility and poor dissolution rate in aqueous environment, however, each having disadvantages and certain limitations. Recently, mesoporous silica materials (MSMs) have been proposed to be used as matrices for enhancing the apparent solubility and dissolution rate of different drug molecules. MSMs are ideal candidates for this purpose, as silica is a "generally regarded as safe" (GRAS) material, is biodegradable, and can be readily surface-modified in order to optimize drug loading and subsequent release in the human body. The major advantage of mesoporous silica as drug delivery systems (DDSs) for poorly water soluble drugs lies in their pore size, pore morphology, and versatility in alteration of the surface groups, which can result in optimized interactions between a drug candidate and MSM carrier by modifying the pore surfaces. Furthermore, the drug of interest can be loaded into these pores in a preferably amorphous state, which can increase the drug dissolution properties dramatically. The highlights of this review include a critical discussion about the modification of the physico-chemical properties of MSMs and how these physico-chemical modifications influence the drug loading and the subsequent dissolution of poorly water soluble drugs. It aims to further promote the use of MSMs as alternative strategy to common methods like solubility enhancement by cyclodextrins, micronization, or microemulsion techniques. This review can provide guidance on how to tailor MSMs to achieve optimized drug loading and drug dissolution.
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Affiliation(s)
- Aziz Maleki
- Zanjan Pharmaceutical Nanotechnology Research Center (ZPNRC), Zanjan University of Medical Sciences, Zanjan, Iran
| | - Helene Kettiger
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Åbo Akademi University, Tykistökatu 6A, FI-20520 Turku, Finland
| | - Aurélie Schoubben
- Department of Pharmaceutical Sciences, University of Perugia, 06123 Perugia, Italy
| | - Jessica M Rosenholm
- Pharmaceutical Sciences Laboratory, Faculty of Science and Engineering, Åbo Akademi University, Tykistökatu 6A, FI-20520 Turku, Finland.
| | - Valeria Ambrogi
- Department of Pharmaceutical Sciences, University of Perugia, 06123 Perugia, Italy.
| | - Mehrdad Hamidi
- Zanjan Pharmaceutical Nanotechnology Research Center (ZPNRC), Zanjan University of Medical Sciences, Zanjan, Iran.
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15
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Shape‐Shifting Patchy Particles. Angew Chem Int Ed Engl 2017; 56:5507-5511. [DOI: 10.1002/anie.201701456] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Revised: 03/09/2017] [Indexed: 11/07/2022]
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16
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Affiliation(s)
- Xiaolong Zheng
- Molecular Design Institute Department of Chemistry New York University New York NY 10003 USA
| | - Mingzhu Liu
- Molecular Design Institute Department of Chemistry New York University New York NY 10003 USA
| | - Mingxin He
- Tandon School of Engineering Department of Chemical & Biomolecular Engineering New York University Brooklyn NY 11201 USA
| | - David J. Pine
- Department of Physics Center for Soft Matter Research New York University New York NY 10003 USA
- Tandon School of Engineering Department of Chemical & Biomolecular Engineering New York University Brooklyn NY 11201 USA
| | - Marcus Weck
- Molecular Design Institute Department of Chemistry New York University New York NY 10003 USA
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17
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Gao Z, Zhao J, Huang Y, Yao X, Zhang K, Fang Y, Nishinari K, Phillips GO, Jiang F, Yang H. Edible Pickering emulsion stabilized by protein fibrils. Part 1: Effects of pH and fibrils concentration. Lebensm Wiss Technol 2017. [DOI: 10.1016/j.lwt.2016.10.038] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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18
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Iron nanoparticles on colloidal substrates. Colloid Polym Sci 2017. [DOI: 10.1007/s00396-016-3972-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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19
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Rotational friction of dipolar colloids measured by driven torsional oscillations. Sci Rep 2016; 6:34193. [PMID: 27680399 PMCID: PMC5040963 DOI: 10.1038/srep34193] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 09/05/2016] [Indexed: 01/02/2023] Open
Abstract
Despite its prominent role in the dynamics of soft materials, rotational friction remains a quantity that is difficult to determine for many micron-sized objects. Here, we demonstrate how the Stokes coefficient of rotational friction can be obtained from the driven torsional oscillations of single particles in a highly viscous environment. The idea is that the oscillation amplitude of a dipolar particle under combined static and oscillating fields provides a measure for the Stokes friction. From numerical studies we derive a semi-empirical analytic expression for the amplitude of the oscillation, which cannot be calculated analytically from the equation of motion. We additionally demonstrate that this expression can be used to experimentally determine the rotational friction coefficient of single particles. Here, we record the amplitudes of a field-driven dipolar Janus microsphere with optical microscopy. The presented method distinguishes itself in its experimental and conceptual simplicity. The magnetic torque leaves the local environment unchanged, which contrasts with other approaches where, for example, additional mechanical (frictional) or thermal contributions have to be regarded.
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20
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Ivanov AO, Kantorovich SS, Zverev VS, Elfimova EA, Lebedev AV, Pshenichnikov AF. Temperature-dependent dynamic correlations in suspensions of magnetic nanoparticles in a broad range of concentrations: a combined experimental and theoretical study. Phys Chem Chem Phys 2016; 18:18342-52. [DOI: 10.1039/c6cp02793h] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study the effects of temperature and concentration on the dynamic spectra of polydisperse magnetic nanoparticle suspensions.
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21
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Hao N, Li L, Tang F. Shape matters when engineering mesoporous silica-based nanomedicines. Biomater Sci 2016; 4:575-91. [DOI: 10.1039/c5bm00589b] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
This review introduces various fabrication methods for non-spherical mesoporous silica nanomaterials and the roles of particle shape in nanomedicine applications.
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Affiliation(s)
- Nanjing Hao
- Technical Institute of Physics and Chemistry
- Chinese Academy of Sciences
- Beijing
- P. R. China
| | - Laifeng Li
- Technical Institute of Physics and Chemistry
- Chinese Academy of Sciences
- Beijing
- P. R. China
| | - Fangqiong Tang
- Technical Institute of Physics and Chemistry
- Chinese Academy of Sciences
- Beijing
- P. R. China
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22
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Baars RJ, van Leeuwen YM, Hendrix Y, Velikov KP, Kegel WK, Philipse AP. Morphology-controlled functional colloids by heterocoagulation of zein and nanoparticles. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2015.04.042] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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Novak EV, Pyanzina ES, Kantorovich SS. Behaviour of magnetic Janus-like colloids. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2015; 27:234102. [PMID: 26010700 DOI: 10.1088/0953-8984/27/23/234102] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We present a theoretical study of Janus-like magnetic particles at low temperature. To describe the basic features of the Janus-type magnetic colloids, we put forward a simple model of a spherical particle with a dipole moment shifted outwards from the centre and oriented perpendicular to the particle radius. Using direct calculations and molecular dynamics computer simulations, we investigate the ground states of small clusters and the behaviour of bigger systems at low temperature. In both cases the important parameter is the dipolar shift, which leads to different ground states and, as a consequence, to a different microscopic behaviour in the situation when the thermal fluctuations are finite. We show that the head-to-tail orientation of dipoles provides a two-particle energy minima only if the dipoles are not shifted from the particle centres. This is one of the key differences from the system of shifted dipolar particles (sd-particles), in which the dipole was shifted outwards radially, studied earlier (Kantorovich et al 2011 Soft Matter 7 5217-27). For sd-particles the dipole could be shifted out of the centre for almost 40% before the head-to-tail orientation was losing its energetic advantage. This peculiarity manifests itself in the topology of the small clusters in the ground state and in the response of the Janus-like particle systems to an external magnetic field at finite temperatures.
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Wang J, Zhu W, Liu L, Chen Y, Wang C. Synthesis and cellular internalization of spindle hematite/polymer hybrid nanoparticles. ACS APPLIED MATERIALS & INTERFACES 2015; 7:5454-5461. [PMID: 25690594 DOI: 10.1021/am509152h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Nonspherical spindle-shaped hematite/polymer hybrid nanoparticles (SPNPs) were synthesized via surface-initiated atom transfer radical polymerization (SI-ATRP). The long axis of the SPNPs was 370 ± 65 nm, and the short axis was 80 ± 15 nm with an aspect ratio of 4.6-4.7. The SPNPs were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS). Thermogravimetric analysis (TGA) was used to estimate the content of grafted polymer. Light-scattering measurement was used to detect the particle size distribution of SPNPs in water and in cell culture medium. HeLa cells internalized the SPNPs within 1 h, and the uptake reached equilibrium in 8 h. These observations contribute to better understanding of the interactions between nonspherical nanoparticles and cells, which may have implication for designing drug delivery vehicles.
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Affiliation(s)
- Jing Wang
- Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, The Chinese Academy of Sciences , Beijing 100190, China
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Vázquez-Vázquez C, Sanlés-Sobrido M, Rodríguez-González B, Spuch-Calvar M, Bañobre-López M, Rivas J, Pérez-Lorenzo M, Salgueiriño V, Correa-Duarte MA. Kinetic impact of Pt seed morphology on the highly controlled growth of Ni-based nanostructures. RSC Adv 2015. [DOI: 10.1039/c5ra05814g] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A Pt seed-mediated growth method for the synthesis of Ni/NiO and Ni/Ni(OH)2 nanocomposites offers an unprecedented control over the morphological and compositional features of Ni-based nanostructures.
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Affiliation(s)
- Carmen Vázquez-Vázquez
- Department of Physical Chemistry
- Biomedical Research Center (CINBIO)
- Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI)
- Universidade de Vigo
- 36310 Vigo
| | - Marcos Sanlés-Sobrido
- Department of Physical Chemistry
- Biomedical Research Center (CINBIO)
- Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI)
- Universidade de Vigo
- 36310 Vigo
| | - Benito Rodríguez-González
- Department of Physical Chemistry
- Biomedical Research Center (CINBIO)
- Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI)
- Universidade de Vigo
- 36310 Vigo
| | - Miguel Spuch-Calvar
- Department of Physical Chemistry
- Biomedical Research Center (CINBIO)
- Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI)
- Universidade de Vigo
- 36310 Vigo
| | | | - José Rivas
- International Iberian Nanotechnology Laboratory (INL)
- 4715-330 Braga
- Portugal
| | - Moisés Pérez-Lorenzo
- Department of Physical Chemistry
- Biomedical Research Center (CINBIO)
- Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI)
- Universidade de Vigo
- 36310 Vigo
| | | | - Miguel A. Correa-Duarte
- Department of Physical Chemistry
- Biomedical Research Center (CINBIO)
- Institute of Biomedical Research of Ourense-Pontevedra-Vigo (IBI)
- Universidade de Vigo
- 36310 Vigo
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Labbé-Laurent M, Tröndle M, Harnau L, Dietrich S. Alignment of cylindrical colloids near chemically patterned substrates induced by critical Casimir torques. SOFT MATTER 2014; 10:2270-2291. [PMID: 24652197 DOI: 10.1039/c3sm52858h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Recent experiments have demonstrated a fluctuation-induced lateral trapping of spherical colloidal particles immersed in a binary liquid mixture near its critical demixing point and exposed to chemically patterned substrates. Inspired by these experiments, we study this kind of effective interaction, known as the critical Casimir effect, for elongated colloids of cylindrical shape. This adds orientational degrees of freedom. When the colloidal particles are close to a chemically structured substrate, a critical Casimir torque acting on the colloids emerges. We calculate this torque on the basis of the Derjaguin approximation. The range of validity of the latter is assessed via mean-field theory. This assessment shows that the Derjaguin approximation is reliable in experimentally relevant regimes, so that we extend it to Janus particles endowed with opposing adsorption preferences. Our analysis indicates that critical Casimir interactions are capable of achieving well-defined, reversible alignments both of chemically homogeneous and of Janus cylinders.
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Affiliation(s)
- M Labbé-Laurent
- Max-Planck-Institut für Intelligente Systeme, Heisenbergstr. 3, D-70569 Stuttgart, Germany.
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27
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Florea D, Wyss HM. Towards the self-assembly of anisotropic colloids: Monodisperse oblate ellipsoids. J Colloid Interface Sci 2014; 416:30-7. [DOI: 10.1016/j.jcis.2013.10.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 10/16/2013] [Accepted: 10/17/2013] [Indexed: 11/27/2022]
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Wang Y, Su X, Ding P, Lu S, Yu H. Shape-controlled synthesis of hollow silica colloids. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:11575-81. [PMID: 23957469 DOI: 10.1021/la402769u] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In this work, hollow silica colloids with different shapes, such as pseudocubes, ellipsoids, capsules, and peanuts, have been synthesized through the following process: silica coating on the surface of hematite colloidal particles with different shapes (pseudocubes, ellipsoids, capsules, and peanuts) and the sequential acid dissolution of the hematite cores. The as-obtained hollow silica colloids with different shapes have uniform sizes, shapes, and shells.
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Affiliation(s)
- Yong Wang
- Department of Chemistry, Capital Normal University , Beijing 100048, China
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29
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Enhanced properties of polyurea elastomeric nanocomposites with anisotropic functionalised nanofillers. POLYMER 2013. [DOI: 10.1016/j.polymer.2013.05.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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30
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KAYTANLI B, VALENTINE M. Evolute-based Hough transform method for characterization of ellipsoids. J Microsc 2013; 249:159-64. [DOI: 10.1111/jmi.12004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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31
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Li N, Zhang Q, Liu J, Joo J, Lee A, Gan Y, Yin Y. Sol–gel coating of inorganic nanostructures with resorcinol–formaldehyde resin. Chem Commun (Camb) 2013; 49:5135-7. [DOI: 10.1039/c3cc41456f] [Citation(s) in RCA: 130] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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32
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Meng X, Guan Y, Zhang Z, Qiu D. Fabrication of a composite colloidal particle with unusual Janus structure as a high-performance solid emulsifier. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2012; 28:12472-12478. [PMID: 22866815 DOI: 10.1021/la302392s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Core-shell particles with cross-linked core and shell were used as seed particles to produce composite Janus particles. It was found that when the shell has distinctly higher cross-linking degree than the core, Janus particles with very unusual structures can be obtained. These particles have two parts, with one part embraced partially or entirely by the other part, adjustable by parameters such as phase ratio or cross-linking degree. On the basis of experimental observations, a possible mechanism for the formation of such unusual Janus particles has been proposed. Janus particles with arms are used to emulsify water-toluene mixtures, forming oil-in-water (O/W) emulsions at very high internal phase content with rather low concentration of particles. Nonspherical emulsion droplets were observed, indicating that these Janus particles are likely to jam at the interface, forming a strong protecting layer to stabilize emulsions.
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Affiliation(s)
- Xiaohui Meng
- Beijing National Laboratory for Molecular Sciences, State Key Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
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33
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Kuipers BWM, van de Ven MCA, Baars RJ, Philipse AP. Simultaneous measurement of rotational and translational diffusion of anisotropic colloids with a new integrated setup for fluorescence recovery after photobleaching. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:245101. [PMID: 22569199 DOI: 10.1088/0953-8984/24/24/245101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
This paper describes an integrated setup for fluorescence recovery after photobleaching (FRAP) for determining translational and rotational Brownian diffusion simultaneously, ensuring that these two quantities are measured under exactly the same conditions and at the same time in dynamic experiments. The setup is based on translational-FRAP with a fringe pattern of light for both the bleaching and monitoring of fluorescently labeled particles, and rotational-FRAP, which uses the polarization of a short bleach light pulse to create a polarization anisotropy. The fringe pattern of the probe beam is modulated in conjunction with a synchronized lock-in amplifier giving a fast, sensitive, ensemble-averaged measurement compared to microscope-image based techniques. The experimental polarization geometry we used ensures that the fluorescence emission is collected without polarization bias. Therefore, only the orientation of the absorption dipole moment of the fixed dye in the particles is measured, which simplifies interpretation of the data. The polarization is modulated rapidly between two orthogonal polarization states, giving the polarization anisotropy in one, single measurement. The rotational and translational Brownian diffusion of anisotropic colloids is measured for ellipsoids of revolution. This experiment shows that in this case the rotational correlation function matches a three-exponential decay in accordance with theoretical predictions.
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Affiliation(s)
- B W M Kuipers
- Van't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute for Nanomaterials Science, Utrecht University, Utrecht, The Netherlands.
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34
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Keller F, Nirschl H, Dörfler W. Primary charge effects on prolate spheroids with moderate aspect ratios. J Colloid Interface Sci 2011; 363:690-702. [PMID: 21855888 DOI: 10.1016/j.jcis.2011.07.081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2011] [Revised: 06/29/2011] [Accepted: 07/25/2011] [Indexed: 10/17/2022]
Abstract
In this article, we investigate the behavior of charged spheroidal colloids with moderate aspect ratios in linear flow fields. We use direct numerical simulation with body-fitted grids for the solution of the Stokes-Poisson-Nernst-Planck system to include all non-linear effects. Therefore, we propose an efficient semi-implicit time discretization based on a splitting of the Stokes equation. We will study the effects of the electric double layer on the forces, torques and on the motion of spheroidal particles. For low Reynolds numbers, we find approximating linear expressions between the ambient fluid flow and the force and torque on the particle. The description of this linear behavior is based on the resistance functions, whose dependencies on the Debye length and the zeta potential are investigated. It is recovered that the resistance functions obey a quadratic dependence on the zeta potential in the small zeta potential regime. For low values of the zeta potential, approximate formulas for the resistance functions are given. The approximation properties are carefully studied by comparing the approximate results with direct numerical simulations. For the case of a shear flow, the approximate formulas can be used to avoid time-consuming direct numerical simulations.
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Affiliation(s)
- Florian Keller
- Institute of Mechanical Process Engineering and Mechanics, Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany.
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35
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Martchenko I, Dietsch H, Moitzi C, Schurtenberger P. Hydrodynamic Properties of Magnetic Nanoparticles with Tunable Shape Anisotropy: Prediction and Experimental Verification. J Phys Chem B 2011; 115:14838-45. [DOI: 10.1021/jp2078264] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ilya Martchenko
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, Route de l’Ancienne Papeterie, CP 209, 1723 Marly 1, Switzerland
- Division of Physical Chemistry, Department of Chemistry, Lund University, Box 124, 22100 Lund, Sweden
| | - Hervé Dietsch
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, Route de l’Ancienne Papeterie, CP 209, 1723 Marly 1, Switzerland
| | | | - Peter Schurtenberger
- Division of Physical Chemistry, Department of Chemistry, Lund University, Box 124, 22100 Lund, Sweden
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36
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Silicon dioxide hollow microspheres with porous composite structure: Synthesis and characterization. J Colloid Interface Sci 2011; 362:253-60. [DOI: 10.1016/j.jcis.2011.06.062] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 06/15/2011] [Accepted: 06/25/2011] [Indexed: 11/24/2022]
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37
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38
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Rufier C, Reufer M, Dietsch H, Schurtenberger P. Single step hybrid coating process to enhance the electrosteric stabilization of inorganic particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2011; 27:6622-6627. [PMID: 21528867 DOI: 10.1021/la200525u] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We report on a single-step coating process and the resulting colloidal stability of silica-coated spindle-type hematite nanoparticles (NPs) decorated with a layer of poly(acrylic acid) (PAA) polyelectrolyte chains that are partially incorporated into the silica shell. The stability of PAA coated NPs as a function of pH and salt concentration in water was compared to bare hematite particles and simple silica-coated hematite NPs, studying their electrophoretic mobility and the hydrodynamic radius by dynamic light scattering. Particles coated with this method were found to be more stable upon the addition of salt at pH 7, and their aggregation at the pH of the isoelectric point is reversible. The hybrid coating appears to increase the colloidal stability in aqueous media due to the combination of the decrease of the isoelectric point and the electrosteric stabilization. This coating method is not limited to hematite particles but can easily be adapted to any silica-coatable particle.
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Affiliation(s)
- Chantal Rufier
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, Route de l'Ancienne Papeterie P.O. Box 209, 1723 Marly 1, Switzerland
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39
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Sacanna S, Pine DJ. Shape-anisotropic colloids: Building blocks for complex assemblies. Curr Opin Colloid Interface Sci 2011. [DOI: 10.1016/j.cocis.2011.01.003] [Citation(s) in RCA: 358] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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40
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Reufer M, Dietsch H, Gasser U, Grobety B, Hirt AM, Malik VK, Schurtenberger P. Magnetic properties of silica coated spindle-type hematite particles. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2011; 23:065102. [PMID: 21406920 DOI: 10.1088/0953-8984/23/6/065102] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Magnetic properties of particles are generally determined from randomly oriented ensembles and the influence of the particle orientation on the magnetic response is neglected. Here, we report on the magnetic characterization of anisotropic spindle-type hematite particles. The easy axis of magnetization is within the basal plane of hematite, which is oriented perpendicular to the spindle axis. Two standard synthesis routes are compared and the effects of silica coating and particle orientation on the magnetic properties are investigated. Depending on the synthesis route we find fundamentally different magnetic behavior compatible with either single domain particles or superparamagnetic sub-units. Furthermore, we show that silica coating reduces the mean blocking temperature to nearly room temperature. The mechanical stress induced by the silica coating appears to reduce the magnetic coupling between the sub-units.
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Affiliation(s)
- M Reufer
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, 1723 Marly, Switzerland
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41
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Nedim Ay A, Konuk D, Zümreoglu-Karan B. Prolate spheroidal hematite particles equatorially belt with drug-carrying layered double hydroxide disks: Ring Nebula-like nanocomposites. NANOSCALE RESEARCH LETTERS 2011; 6:116. [PMID: 21711652 PMCID: PMC3211161 DOI: 10.1186/1556-276x-6-116] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/25/2010] [Accepted: 02/03/2011] [Indexed: 05/31/2023]
Abstract
A new nanocomposite architecture is reported which combines prolate spheroidal hematite nanoparticles with drug-carrying layered double hydroxide [LDH] disks in a single structure. Spindle-shaped hematite nanoparticles with average length of 225 nm and width of 75 nm were obtained by thermal decomposition of hydrothermally synthesized hematite. The particles were first coated with Mg-Al-NO3-LDH shell and then subjected to anion exchange with salicylate ions. The resulting bio-nanohybrid displayed a close structural resemblance to that of the Ring Nebula. Scanning electron microscope and transmission electron microscopy images showed that the LDH disks are stacked around the equatorial part of the ellipsoid extending along the main axis. This geometry possesses great structural tunability as the composition of the LDH and the nature of the interlayer region can be tailored and lead to novel applications in areas ranging from functional materials to medicine by encapsulating various guest molecules.
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Affiliation(s)
- Ahmet Nedim Ay
- Department of Chemistry, Hacettepe University, Beytepe Campus, 06800 Ankara, Turkey
| | - Deniz Konuk
- Department of Chemistry, Hacettepe University, Beytepe Campus, 06800 Ankara, Turkey
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42
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Sánchez-Ferrer A, Mezzenga R, Dietsch H. Orientational Behavior of Ellipsoidal Silica-Coated Hematite Nanoparticles Integrated within an Elastomeric Matrix and its Mechanical Reinforcement. MACROMOL CHEM PHYS 2011. [DOI: 10.1002/macp.201000720] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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43
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Sánchez-Ferrer A, Reufer M, Mezzenga R, Schurtenberger P, Dietsch H. Inorganic-organic elastomer nanocomposites from integrated ellipsoidal silica-coated hematite nanoparticles as crosslinking agents. NANOTECHNOLOGY 2010; 21:185603. [PMID: 20388973 DOI: 10.1088/0957-4484/21/18/185603] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We report on the synthesis of nanocomposites with integrated ellipsoidal silica-coated hematite (SCH) spindle type nanoparticles which can act as crosslinking agents within an elastomeric matrix. Influence of the surface chemistry of the hematite, leading either to dispersed particles or crosslinked particles to the elastomer matrix, was studied via swelling, scattering and microscopy experiments. It appeared that without surface modification the SCH particles aggregate and act as defects whereas the surface modified SCH particles increase the crosslinking density and thus reduce the swelling properties of the nanocomposite in good solvent conditions. For the first time, inorganic SCH particles can be easily dispersed into a polymer network avoiding aggregation and enhancing the properties of the resulting inorganic-organic elastomer nanocomposite (IOEN).
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Affiliation(s)
- A Sánchez-Ferrer
- ETH Zurich, Institute of Food, Nutrition & Health, Food & Soft Materials Science Group, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
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44
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Nagao D, van Kats CM, Hayasaka K, Sugimoto M, Konno M, Imhof A, van Blaaderen A. Synthesis of hollow asymmetrical silica dumbbells with a movable inner core. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2010; 26:5208-12. [PMID: 20073531 DOI: 10.1021/la903673j] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Hollow asymmetrical silica dumbbells containing a movable inner core were fabricated by a template-assisted method. Three different templates were employed for the fabrication of the hollow asymmetrical dumbbells. For the preparation of the first template, silica particles were uniformly covered with a cross-linked polymethylmethacrylate (PMMA) shell and the polymerization of styrene was conducted to induce a protrusion of polystyrene (PSt) from the PMMA shell. Anisotropic colloids composed of silica, PMMA, and PSt were used as templates, coated with a silica shell, and held at 500 degrees C for 2 h to remove the polymer interior components of the template colloid. The heat treatment successfully produced hollow asymmetrical silica dumbbells containing an inner silica core. After being dried, approximately 50% of the inner silica particles that were originally coated with PMMA ended up in the other hollow sphere in which the PSt component existed before heat treatment, indicating that the inner silica particles could pass through the hollow asymmetrical dumbbells' necks and were free to move in the interior. In the preparation of the second and third asymmetrical dumbbell templates, magnetic silica particles and titania particles, respectively, were covered with a PMMA shell to incorporate externally responsive particles into the hollow silica shells as above. The successful syntheses demonstrated the generality of our approach. The passage of the responsive particles through the dumbbell's neck enabled active control of the position of the responsive particles inside the asymmetrical dumbbells by external fields.
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Affiliation(s)
- Daisuke Nagao
- Department of Chemical Engineering, Graduate School of Engineering, Tohoku University 6-6-07 Aoba, Aramaki-aza Aoba-ku, Sendai, 980-8579, Japan.
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45
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Reufer M, Dietsch H, Gasser U, Hirt A, Menzel A, Schurtenberger P. Morphology and Orientational Behavior of Silica-Coated Spindle-Type Hematite Particles in a Magnetic Field Probed by Small-Angle X-ray Scattering. J Phys Chem B 2010; 114:4763-9. [DOI: 10.1021/jp911817e] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Mathias Reufer
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, 1723 Marly, Switzerland, Laboratory for Neutron Scattering, ETH Zürich & Paul Scherrer Institut, 5232 Villigen PSI, Switzerland, Institute for Geophysics, ETH Zürich, Switzerland, and Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Hervé Dietsch
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, 1723 Marly, Switzerland, Laboratory for Neutron Scattering, ETH Zürich & Paul Scherrer Institut, 5232 Villigen PSI, Switzerland, Institute for Geophysics, ETH Zürich, Switzerland, and Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Urs Gasser
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, 1723 Marly, Switzerland, Laboratory for Neutron Scattering, ETH Zürich & Paul Scherrer Institut, 5232 Villigen PSI, Switzerland, Institute for Geophysics, ETH Zürich, Switzerland, and Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Ann Hirt
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, 1723 Marly, Switzerland, Laboratory for Neutron Scattering, ETH Zürich & Paul Scherrer Institut, 5232 Villigen PSI, Switzerland, Institute for Geophysics, ETH Zürich, Switzerland, and Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Andreas Menzel
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, 1723 Marly, Switzerland, Laboratory for Neutron Scattering, ETH Zürich & Paul Scherrer Institut, 5232 Villigen PSI, Switzerland, Institute for Geophysics, ETH Zürich, Switzerland, and Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
| | - Peter Schurtenberger
- Adolphe Merkle Institute and Fribourg Center for Nanomaterials, University of Fribourg, 1723 Marly, Switzerland, Laboratory for Neutron Scattering, ETH Zürich & Paul Scherrer Institut, 5232 Villigen PSI, Switzerland, Institute for Geophysics, ETH Zürich, Switzerland, and Swiss Light Source, Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
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46
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Guerrero-Martínez A, Pérez-Juste J, Liz-Marzán LM. Recent progress on silica coating of nanoparticles and related nanomaterials. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2010; 22:1182-95. [PMID: 20437506 DOI: 10.1002/adma.200901263] [Citation(s) in RCA: 417] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
In recent years, new strategies for silica coating of inorganic nanoparticles and organic nanomaterials, which differ from the classical methodologies, have emerged at the forefront of materials science. Silica as a coating material promises an unparalleled opportunity for enhancement of colloidal properties and functions by using core-shell rational designs and profiting from its synthetic versatility. This contribution provides a brief overview of recent progress in the synthesis of silica-coated nanomaterials and their significant impact in different areas such as spectroscopy, magnetism, catalysis, and biology.
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Affiliation(s)
- Andrés Guerrero-Martínez
- Departamento de Química Física and Unidad Asociada CSIC Universidade de Vigo, Vigo 36310, Spain.
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47
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Kondrat S, Harnau L, Dietrich S. Critical Casimir interaction of ellipsoidal colloids with a planar wall. J Chem Phys 2009; 131:204902. [DOI: 10.1063/1.3259188] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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48
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Zhu C, Chen L, Xu H, Gu Z. A Magnetically Tunable Colloidal Crystal Film for Reflective Display. Macromol Rapid Commun 2009; 30:1945-9. [DOI: 10.1002/marc.200900392] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Revised: 07/16/2009] [Indexed: 11/08/2022]
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Gromenko O, Privman V. Random sequential adsorption of oriented superdisks. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:042103. [PMID: 19518281 DOI: 10.1103/physreve.79.042103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2009] [Indexed: 05/27/2023]
Abstract
In this work we extend recent study of the properties of the dense packing of "superdisks," by Y. Jiao [Phys. Rev. Lett. 100, 245504 (2008)] to the jammed state formed by these objects in random sequential adsorption. The superdisks are two-dimensional shapes bound by the curves of the form |x|2p+|y|2p=1, with p>0. We use Monte Carlo simulations and theoretical arguments to establish that p=1/2 is a special point at which the jamming density, rhoJ(p), has a discontinuous derivative as a function of p . The existence of this point can be also argued for by a phenomenological excluded-area argument.
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Affiliation(s)
- Oleksandr Gromenko
- Department of Physics, Clarkson University, Potsdam, New York 13699, USA
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Pacifico J, van Leeuwen YM, Spuch-Calvar M, Sánchez-Iglesias A, Rodríguez-Lorenzo L, Pérez-Juste J, Pastoriza-Santos I, Liz-Marzán LM. Field gradient imaging of nanoparticle systems: analysis of geometry and surface coating effects. NANOTECHNOLOGY 2009; 20:095708. [PMID: 19417504 DOI: 10.1088/0957-4484/20/9/095708] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In this work we compare the standard imaging of various types of nanoparticles deposited on surfaces by atomic force microscopy (AFM) with a complementary analysis of the same samples by either electrostatic force microscopy (EFM) or magnetic force microscopy (MFM). Experiments were carried out on gold nanoparticles (decahedrons and stars) and two different iron oxide systems: goethite (alpha-FeOOH) and hematite (alpha-Fe(2)O(3)). Regardless of the particular geometry, the EFM signal appears to be stronger on edges or tips of pure gold nanoparticles. Both EFM and MFM experiments were also carried out on iron oxide particles. Apart from the structural analysis, we analyzed the influence of a shell layer deposited on the gold and iron oxide particles, the shell being amorphous SiO(2). Although the silica layer was found to have an insulating effect around the particles, in all cases EFM/MFM measurements could still be performed by the proper choice of the scan lift height (with an eventual slight increase of the sample bias, where applicable).
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Affiliation(s)
- J Pacifico
- Departamento de Química Física, and Unidad Asociada CSIC, Universidade de Vigo, Vigo, Spain.
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