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Danielsen SPO, Beech HK, Wang S, El-Zaatari BM, Wang X, Sapir L, Ouchi T, Wang Z, Johnson PN, Hu Y, Lundberg DJ, Stoychev G, Craig SL, Johnson JA, Kalow JA, Olsen BD, Rubinstein M. Molecular Characterization of Polymer Networks. Chem Rev 2021; 121:5042-5092. [PMID: 33792299 DOI: 10.1021/acs.chemrev.0c01304] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Polymer networks are complex systems consisting of molecular components. Whereas the properties of the individual components are typically well understood by most chemists, translating that chemical insight into polymer networks themselves is limited by the statistical and poorly defined nature of network structures. As a result, it is challenging, if not currently impossible, to extrapolate from the molecular behavior of components to the full range of performance and properties of the entire polymer network. Polymer networks therefore present an unrealized, important, and interdisciplinary opportunity to exert molecular-level, chemical control on material macroscopic properties. A barrier to sophisticated molecular approaches to polymer networks is that the techniques for characterizing the molecular structure of networks are often unfamiliar to many scientists. Here, we present a critical overview of the current characterization techniques available to understand the relation between the molecular properties and the resulting performance and behavior of polymer networks, in the absence of added fillers. We highlight the methods available to characterize the chemistry and molecular-level properties of individual polymer strands and junctions, the gelation process by which strands form networks, the structure of the resulting network, and the dynamics and mechanics of the final material. The purpose is not to serve as a detailed manual for conducting these measurements but rather to unify the underlying principles, point out remaining challenges, and provide a concise overview by which chemists can plan characterization strategies that suit their research objectives. Because polymer networks cannot often be sufficiently characterized with a single method, strategic combinations of multiple techniques are typically required for their molecular characterization.
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Affiliation(s)
- Scott P O Danielsen
- Marsico Lung Institute, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Haley K Beech
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Shu Wang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Bassil M El-Zaatari
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Xiaodi Wang
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | | | | | - Zi Wang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Patricia N Johnson
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Yixin Hu
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - David J Lundberg
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Georgi Stoychev
- Marsico Lung Institute, University of North Carolina, Chapel Hill, North Carolina 27599, United States
| | - Stephen L Craig
- Department of Chemistry, Duke University, Durham, North Carolina 27708, United States
| | - Jeremiah A Johnson
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Julia A Kalow
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Bradley D Olsen
- Department of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Michael Rubinstein
- Marsico Lung Institute, University of North Carolina, Chapel Hill, North Carolina 27599, United States.,Department of Chemistry, Duke University, Durham, North Carolina 27708, United States.,Departments of Biomedical Engineering and Physics, Duke University, Durham, North Carolina 27708, United States.,World Primer Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 21 Nishi 10, Kita-ku, Sapporo, Hokkaido 001-0021, Japan
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Kirillova A, Maxson R, Stoychev G, Gomillion CT, Ionov L. 4D Biofabrication Using Shape-Morphing Hydrogels. Adv Mater 2017; 29:1703443. [PMID: 29024044 DOI: 10.1002/adma.201703443] [Citation(s) in RCA: 182] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 09/05/2017] [Indexed: 06/07/2023]
Abstract
Despite the tremendous potential of bioprinting techniques toward the fabrication of highly complex biological structures and the flourishing progress in 3D bioprinting, the most critical challenge of the current approaches is the printing of hollow tubular structures. In this work, an advanced 4D biofabrication approach, based on printing of shape-morphing biopolymer hydrogels, is developed for the fabrication of hollow self-folding tubes with unprecedented control over their diameters and architectures at high resolution. The versatility of the approach is demonstrated by employing two different biopolymers (alginate and hyaluronic acid) and mouse bone marrow stromal cells. Harnessing the printing and postprinting parameters allows attaining average internal tube diameters as low as 20 µm, which is not yet achievable by other existing bioprinting/biofabrication approaches and is comparable to the diameters of the smallest blood vessels. The proposed 4D biofabrication process does not pose any negative effect on the viability of the printed cells, and the self-folded hydrogel-based tubes support cell survival for at least 7 d without any decrease in cell viability. Consequently, the presented 4D biofabrication strategy allows the production of dynamically reconfigurable architectures with tunable functionality and responsiveness, governed by the selection of suitable materials and cells.
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Affiliation(s)
- Alina Kirillova
- College of Engineering, University of Georgia, Athens, GA, 30602, USA
| | - Ridge Maxson
- College of Engineering, University of Georgia, Athens, GA, 30602, USA
| | - Georgi Stoychev
- College of Engineering, University of Georgia, Athens, GA, 30602, USA
| | | | - Leonid Ionov
- College of Engineering, University of Georgia, Athens, GA, 30602, USA
- College of Family and Consumer Sciences, University of Georgia, Athens, GA, 30602, USA
- Faculty of Engineering Science, University of Bayreuth, Universitätsstr. 30, 95440, Bayreuth, Germany
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Apsite I, Stoychev G, Zhang W, Jehnichen D, Xie J, Ionov L. Porous Stimuli-Responsive Self-Folding Electrospun Mats for 4D Biofabrication. Biomacromolecules 2017; 18:3178-3184. [DOI: 10.1021/acs.biomac.7b00829] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
| | | | | | - Dieter Jehnichen
- Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany
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Abstract
There exist many methods for processing of materials: extrusion, injection molding, fibers spinning, 3D printing, to name a few. In most cases, materials with a static, fixed shape are produced. However, numerous advanced applications require customized elements with reconfigurable shape. The few available techniques capable of overcoming this problem are expensive and/or time-consuming. Here, the use of one of the most ancient technologies for structuring, embroidering, is proposed to generate sophisticated patterns of active materials, and, in this way, to achieve complex actuation. By combining experiments and computational modeling, the fundamental rules that can predict the folding behavior of sheets with a variety of stitch-patterns are elucidated. It is demonstrated that theoretical mechanics analysis is only suitable to predict the behavior of the simplest experimental setups, whereas computer modeling gives better predictions for more complex cases. Finally, the applicability of the rules by designing basic origami structures and wrinkling substrates with controlled thermal insulation properties is shown.
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Affiliation(s)
- Georgi Stoychev
- College of Family and Consumer Sciences, University of Georgia, Athens, GA, 30602, USA.,Driftmier Engineering Center, UGA College of Engineering, 597 DW Brooks Drive, Athens, GA, 30602, USA
| | - Mir Jalil Razavi
- Driftmier Engineering Center, UGA College of Engineering, 597 DW Brooks Drive, Athens, GA, 30602, USA
| | - Xianqiao Wang
- Driftmier Engineering Center, UGA College of Engineering, 597 DW Brooks Drive, Athens, GA, 30602, USA
| | - Leonid Ionov
- College of Family and Consumer Sciences, University of Georgia, Athens, GA, 30602, USA.,Driftmier Engineering Center, UGA College of Engineering, 597 DW Brooks Drive, Athens, GA, 30602, USA
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5
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Ionov L, Stoychev G, Jehnichen D, Sommer JU. Correction to "Reversibly Actuating Solid Janus Polymeric Fibers". ACS Appl Mater Interfaces 2017; 9:25642. [PMID: 28723070 DOI: 10.1021/acsami.7b08820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
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Abstract
It is commonly assumed that the substantial element of reversibly actuating soft polymeric materials is chemical cross-linking, which is needed to provide elasticity required for the reversible actuation. On the example of melt spun and three-dimensional printed Janus fibers, we demonstrate here for the first time that cross-linking is not an obligatory prerequisite for reversible actuation of solid entangled polymers, since the entanglement network itself can build elasticity during crystallization. Indeed, we show that not-cross-linked polymers, which typically demonstrate plastic deformation in melt, possess enough elastic behavior to actuate reversibly. The Janus polymeric structure bends because of contraction of the polymer and due to entanglements and formation of nanocrystallites upon cooling. Actuation upon melting is simply due to relaxation of the stressed nonfusible component. This approach opens perspectives for design of solid active materials and actuator for robotics, biotechnology, and smart textile applications. The great advantage of our principle is that it allows design of non-cross-linked self-moving materials, which are able to actuate in both water and air, which are not cross-linked. We demonstrate application of actuating fibers for design of walkers, structures with switchable length, width, and thickness, which can be used for smart textile applications.
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Affiliation(s)
- Leonid Ionov
- College of Engineering, College of Family and Consumer Sciences, University of Georgia , Athens, Georgia 30602, United States
| | - Georgi Stoychev
- College of Engineering, College of Family and Consumer Sciences, University of Georgia , Athens, Georgia 30602, United States
| | - Dieter Jehnichen
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Str. 6, 01069 Dresden, Germany
| | - Jens Uwe Sommer
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Str. 6, 01069 Dresden, Germany
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Stoychev G, Reuther C, Diez S, Ionov L. Controlled Retention and Release of Biomolecular Transport Systems Using Shape-Changing Polymer Bilayers. Angew Chem Int Ed Engl 2016; 55:16106-16109. [PMID: 27882699 DOI: 10.1002/anie.201608299] [Citation(s) in RCA: 10] [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: 08/24/2016] [Revised: 10/02/2016] [Indexed: 11/11/2022]
Abstract
Biomolecular transport systems based on cytoskeletal filaments and motor proteins have become promising tools for a wide range of nanotechnological applications. In this paper, we report control of such transport systems using substrates with switchable shape. We demonstrate this approach on the example of microtubules gliding on surfaces of self-folding polymer bilayers with adsorbed kinesin motors. The polymer bilayers are able to undergo reversible transitions between flat and tube-like shapes that allow the externally controlled retention and release of gliding microtubules. The demonstrated approach, based on surfaces with reconfigurable topography, opens broad perspectives to control biomolecular transport systems for bioanalytical and sensing applications, as well as for the construction of subcellular compartments in the field of synthetic biology.
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Affiliation(s)
- Georgi Stoychev
- College of Engineering, College of Family and Consumer Sciences, University of Georgia, Athens, GA, 30602, USA.,Leibniz Institute of Polymer Research e.V. Dresden, Hohe Str. 6, 01069, Dresden, Germany
| | - Cordula Reuther
- B CUBE-Center for Molecular Bioengineering, Technische Universität Dresden and Max-Planck-Institute of Molecular Cell Biology and Genetics, 01307, Dresden, Germany
| | - Stefan Diez
- B CUBE-Center for Molecular Bioengineering, Technische Universität Dresden and Max-Planck-Institute of Molecular Cell Biology and Genetics, 01307, Dresden, Germany
| | - Leonid Ionov
- College of Engineering, College of Family and Consumer Sciences, University of Georgia, Athens, GA, 30602, USA.,Leibniz Institute of Polymer Research e.V. Dresden, Hohe Str. 6, 01069, Dresden, Germany
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Stoychev G, Reuther C, Diez S, Ionov L. Controlled Retention and Release of Biomolecular Transport Systems Using Shape-Changing Polymer Bilayers. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201608299] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Georgi Stoychev
- College of Engineering, College of Family and Consumer Sciences; University of Georgia; Athens GA 30602 USA
- Leibniz Institute of Polymer Research e.V. Dresden; Hohe Str. 6 01069 Dresden Germany
| | - Cordula Reuther
- B CUBE-Center for Molecular Bioengineering; Technische Universität Dresden and Max-Planck-Institute of Molecular Cell Biology and Genetics; 01307 Dresden Germany
| | - Stefan Diez
- B CUBE-Center for Molecular Bioengineering; Technische Universität Dresden and Max-Planck-Institute of Molecular Cell Biology and Genetics; 01307 Dresden Germany
| | - Leonid Ionov
- College of Engineering, College of Family and Consumer Sciences; University of Georgia; Athens GA 30602 USA
- Leibniz Institute of Polymer Research e.V. Dresden; Hohe Str. 6 01069 Dresden Germany
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9
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Ennen F, Fenner P, Stoychev G, Boye S, Lederer A, Voit B, Appelhans D. Coil-like Enzymatic Biohybrid Structures Fabricated by Rational Design: Controlling Size and Enzyme Activity over Sequential Nanoparticle Bioconjugation and Filtration Steps. ACS Appl Mater Interfaces 2016; 8:6261-8. [PMID: 26905671 DOI: 10.1021/acsami.5b07305] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Well-defined enzymatic biohybrid structures (BHS) composed of avidin, biotinylated poly(propyleneimine) glycodendrimers, and biotinylated horseradish peroxidase were fabricated by a sequential polyassociation reaction to adopt directed enzyme prodrug therapy to protein-glycopolymer BHS for potential biomedical applications. To tailor and gain fundamental insight into pivotal properties such as size and molar mass of these BHS, the dependence on the fabrication sequence was probed and thoroughly investigated by several complementary methods (e.g., UV/vis, DLS, cryoTEM, AF4-LS). Subsequent purification by hollow fiber filtration allowed us to obtain highly pure and well-defined BHS. Overall, by rational design and control of preparation parameters, e.g., fabrication sequence, ligand-receptor stoichiometry, and degree of biotinylation, well-defined BHS with stable and even strongly enhanced enzymatic activities can be achieved. Open coil-like structures of BHS with few branches are available by the sequential bioconjugation approach between synthetic and biological macromolecules possessing similar size dimensions.
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Affiliation(s)
- Franka Ennen
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
- Organische Chemie der Polymere, Technische Universität Dresden , 01062 Dresden, Germany
| | - Philipp Fenner
- Organische Chemie der Polymere, Technische Universität Dresden , 01062 Dresden, Germany
| | - Georgi Stoychev
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
- Organische Chemie der Polymere, Technische Universität Dresden , 01062 Dresden, Germany
| | - Susanne Boye
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
| | - Albena Lederer
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
- Organische Chemie der Polymere, Technische Universität Dresden , 01062 Dresden, Germany
| | - Brigitte Voit
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
- Organische Chemie der Polymere, Technische Universität Dresden , 01062 Dresden, Germany
| | - Dietmar Appelhans
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
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Abstract
The exploitation of colloidal building blocks with morphological and functional anisotropy facilitates the generation of complex structures with unique properties, which are not exhibited by isotropic particle assemblies. Herein, we demonstrate an easy and scalable bottom-up approach for the programmed assembly of hairy oppositely charged homogeneously decorated and Janus particles based on electrostatic interactions mediated by polyelectrolytes grafted onto their surface. Two different assembly routes are proposed depending on the target structures: raspberry-like/half-raspberry-like or dumbbell-like micro-clusters. Ultimately, stable symmetric and asymmetric micro-structures could be obtained in a well-controlled manner for the homogeneous–homogeneous and homogeneous–Janus particle assemblies, respectively. The spatially separated functionalities of the asymmetric Janus particle-based micro-clusters allow their further assembly into complex hierarchical constructs, which may potentially lead to the design of materials with tailored plasmonics and optical properties.
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Affiliation(s)
- Alina Kirillova
- Leibniz Institute of Polymer Research Dresden
- 01069 Dresden
- Germany
- Technische Universität Dresden
- Fakultät Mathematik und Naturwissenschaften
| | - Georgi Stoychev
- Leibniz Institute of Polymer Research Dresden
- 01069 Dresden
- Germany
- Technische Universität Dresden
- Fakultät Mathematik und Naturwissenschaften
| | - Alla Synytska
- Leibniz Institute of Polymer Research Dresden
- 01069 Dresden
- Germany
- Technische Universität Dresden
- Fakultät Mathematik und Naturwissenschaften
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Kirillova A, Schliebe C, Stoychev G, Jakob A, Lang H, Synytska A. Hybrid Hairy Janus Particles Decorated with Metallic Nanoparticles for Catalytic Applications. ACS Appl Mater Interfaces 2015; 7:21218-21225. [PMID: 26357969 DOI: 10.1021/acsami.5b05224] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report for the first time on the design of an advanced hairy hybrid Janus-type catalyst, which is comprised of an inorganic silica core covered with two distinct polymeric shells (hydrophilic and hydrophobic) on its opposite sides, while the catalytic species (in our case silver or gold nanoparticles) are immobilized directly into the hydrophilic stimuli-responsive polymer shell. The primary 200 nm large Janus particles with poly(acrylic acid) serving as the hydrophilic and polystyrene as the hydrophobic polymer were synthesized through a Pickering emulsion and a combination of "grafting from"/"grafting to" approaches. The incorporation of silver and gold nanoparticles within the hydrophilic polymer shell was achieved by infiltrating the respective metal ions into the polymer matrix, and nanoparticles were formed upon the addition of a reducing agent (triethylamine). Plasmon absorptions typical for silver and gold nanostructures were observed on the functionalized Janus particles using UV-vis spectroscopy. The respective systems were investigated by TEM and cryo-TEM revealing that the incorporated nanoparticles are selectively localized on the poly(acrylic acid) side of the Janus particles. The efficiency of the catalyst as well as the accessibility of the incorporated nanoparticles was tested on the reduction of Methylene Blue, Eosin Y, and 4-nitrophenol as convenient benchmark systems. Ultimately, the hairy Janus particles with immobilized Ag or Au nanoparticles efficiently catalyzed the respective reactions by applying extremely low amounts of catalyst. Finally, we demonstrated several advantages of the use of JPs with immobilized metallic nanoparticles, which are (i) JPs stabilize the emulsions, (ii) the emulsion can be destabilized by utilizing responsive properties of the JPs, and (iii) JPs can easily be recovered after reaction and reused again.
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Affiliation(s)
- Alina Kirillova
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
- Technische Universität Dresden , Physical Chemistry of Polymer Materials, 01062 Dresden, Germany
| | - Christian Schliebe
- Technische Universität Chemnitz , Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, 09107 Chemnitz, Germany
| | - Georgi Stoychev
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
- Technische Universität Dresden , Physical Chemistry of Polymer Materials, 01062 Dresden, Germany
| | - Alexander Jakob
- Technische Universität Chemnitz , Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, 09107 Chemnitz, Germany
| | - Heinrich Lang
- Technische Universität Chemnitz , Faculty of Natural Sciences, Institute of Chemistry, Inorganic Chemistry, 09107 Chemnitz, Germany
| | - Alla Synytska
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, 01069 Dresden, Germany
- Technische Universität Dresden , Physical Chemistry of Polymer Materials, 01062 Dresden, Germany
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Kirillova A, Stoychev G, Ionov L, Synytska A. Self-assembly behavior of hairy colloidal particles with different architectures: mixed versus janus. Langmuir 2014; 30:12765-12774. [PMID: 25294255 DOI: 10.1021/la503455h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this paper, we investigated the aggregation and assembly behavior of hairy core-shell particles with different architectures consisting of a hard silica core and soft polymer brush shells. We varied the nature of the polymers which form the shell: we used different hydrophilic positively (poly(2-(dimethylamino)ethyl methacrylate), PDMAEMA) and negatively (poly(acrylic acid), PAA) charged polymers, uncharged hydrophilic (polyethylene glycol, PEG) polymers, and hydrophobic (poly(lauryl methacrylate), PLMA; polystyrene, PS) polymers. We synthesized particles covered by polymer of one sort (homogeneously coated particles) as well as Janus particles (two polymers are grafted to the opposite sides of the core) and investigated/compared the aggregation behavior of different fully covered particles, their mixtures, and Janus particles.
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Affiliation(s)
- A Kirillova
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Str. 6, 01069 Dresden, Germany
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Kirillova A, Stoychev G, Ionov L, Eichhorn KJ, Malanin M, Synytska A. Platelet Janus particles with hairy polymer shells for multifunctional materials. ACS Appl Mater Interfaces 2014; 6:13106-13114. [PMID: 25019217 DOI: 10.1021/am502973y] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A novel approach is developed for the large-scale synthesis of Janus particles with platelet geometry and dense polymer shells by employing simultaneous "grafting from" of hydrophilic and hydrophobic polymers using surface-induced ATRP in emulsion. The method is based on the fabrication of an emulsion consisting of a water solution of a hydrophilic monomer and a solution of a hydrophobic monomer in an organic solvent, which is stabilized by initiator-modified kaolinite particles. Two polymers are grafted simultaneously on the opposite faces of the kaolinite particle during polymerization. The synthesized particles have a clear Janus character and are highly efficient for the stabilization of emulsions. Because of its simplicity, the method can readily be upscaled for the synthesis of large amounts of Janus particles, up to several grams.
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Affiliation(s)
- Alina Kirillova
- Leibniz-Institut für Polymerforschung Dresden e.V. , Hohe Strasse 6, D-01069 Dresden, Germany
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Abstract
Flexible thermoresponsive polymeric microjets are formed by the self-folding of polymeric layers containing a thin Pt film used as catalyst for self-propulsion in solutions containing hydrogen peroxide. The flexible microjets can reversibly fold and unfold in an accurate manner by applying changes in temperature to the solution in which they are immersed. This effect allows microjets to rapidly start and stop multiple times by controlling the radius of curvature of the microjet. This work opens many possibilities in the field of artificial nanodevices, for fundamental studies on self-propulsion at the microscale, and also for biorelated applications.
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Affiliation(s)
- Veronika Magdanz
- Institute for Integrative Nanosciences, Leibniz Institute for Solid State and Materials Research DresdenHelmholtz Strasse 20, 01069 Dresden (Germany)
| | - Georgi Stoychev
- Leibniz Institute of Polymer Research DresdenHohe Strasse 6, 01069 Dresden (Germany)
- Technische Universität Dresden, Fakultät Mathematik und Naturwissenschaften01062, Dresden (Germany)
| | - Leonid Ionov
- Leibniz Institute of Polymer Research DresdenHohe Strasse 6, 01069 Dresden (Germany)
| | - Samuel Sanchez
- Current affiliation: Max Planck Institute for Intelligent SystemsHeisenbergstrasse 3, 70569 Stuttgart (Germany)
- Institute for Integrative Nanosciences, Leibniz Institute for Solid State and Materials Research DresdenHelmholtz Strasse 20, 01069 Dresden (Germany)
| | - Oliver G Schmidt
- Institute for Integrative Nanosciences, Leibniz Institute for Solid State and Materials Research DresdenHelmholtz Strasse 20, 01069 Dresden (Germany)
- Material Systems for Nanoelectronics, Technische Universität ChemnitzReichenhainer Strasse 70, 09107 Chemnitz (Germany)
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Kudina O, Zakharchenko A, Trotsenko O, Tokarev A, Ionov L, Stoychev G, Puretskiy N, Pryor SW, Voronov A, Minko S. Titelbild: Highly Efficient Phase Boundary Biocatalysis with Enzymogel Nanoparticles (Angew. Chem. 2/2014). Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201309903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kudina O, Zakharchenko A, Trotsenko O, Tokarev A, Ionov L, Stoychev G, Puretskiy N, Pryor SW, Voronov A, Minko S. Cover Picture: Highly Efficient Phase Boundary Biocatalysis with Enzymogel Nanoparticles (Angew. Chem. Int. Ed. 2/2014). Angew Chem Int Ed Engl 2014. [DOI: 10.1002/anie.201309903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kudina O, Zakharchenko A, Trotsenko O, Tokarev A, Ionov L, Stoychev G, Puretskiy N, Pryor SW, Voronov A, Minko S. Highly Efficient Phase Boundary Biocatalysis with Enzymogel Nanoparticles. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201306831] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Kudina O, Zakharchenko A, Trotsenko O, Tokarev A, Ionov L, Stoychev G, Puretskiy N, Pryor SW, Voronov A, Minko S. Highly Efficient Phase Boundary Biocatalysis with Enzymogel Nanoparticles. Angew Chem Int Ed Engl 2013; 53:483-7. [DOI: 10.1002/anie.201306831] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 10/03/2013] [Indexed: 11/06/2022]
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Zakharchenko S, Puretskiy N, Stoychev G, Waurisch C, Hickey SG, Eychmüller A, Sommer JU, Ionov L. Stimuli-responsive hierarchically self-assembled 3D porous polymer-based structures with aligned pores. J Mater Chem B 2013; 1:1786-1793. [DOI: 10.1039/c2tb00231k] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
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Stoychev G, Zakharchenko S, Turcaud S, Dunlop JWC, Ionov L. Shape-programmed folding of stimuli-responsive polymer bilayers. ACS Nano 2012; 6:3925-3934. [PMID: 22530752 DOI: 10.1021/nn300079f] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We investigated the folding of rectangular stimuli-responsive hydrogel-based polymer bilayers with different aspect ratios and relative thicknesses placed on a substrate. It was found that long-side rolling dominates at high aspect ratios (ratio of length to width) when the width is comparable to the circumference of the formed tubes, which corresponds to a small actuation strain. Rolling from all sides occurs for higher actuation, namely when the width and length considerably exceed the deformed circumference. In the case of moderate actuation, when both the width and length are comparable to the deformed circumference, diagonal rolling is observed. Short-side rolling was observed very rarely and in combination with diagonal rolling. On the basis of experimental observations, finite-element modeling and energetic considerations, we argued that bilayers placed on a substrate start to roll from corners due to quicker diffusion of water. Rolling from the long-side starts later but dominates at high aspect ratios, in agreement with energetic considerations. We have shown experimentally and by modeling that the main reasons causing a variety of rolling scenarios are (i) non-homogenous swelling due to the presence of the substrate and (ii) adhesion of the polymer to the substrate.
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Affiliation(s)
- Georgi Stoychev
- Leibniz Institute of Polymer Research Dresden, Hohe Strasse 6, D-01069 Dresden, Germany
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Puretskiy N, Stoychev G, Synytska A, Ionov L. Surfaces with self-repairable ultrahydrophobicity based on self-organizing freely floating colloidal particles. Langmuir 2012; 28:3679-3682. [PMID: 22324293 DOI: 10.1021/la204232g] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We report an approach for the design of materials with self-repairable ultrahydrophobic properties. The materials are based on highly fluorinated crystalline fusible wax with incorporated colloidal particles. Due to the highly pronounced tendency of the wax to crystallize, the formation of blends with rough fractal surfaces was observed. In order to prove their self-repairing ability, we mechanically damaged them by scratching, which removed most of the particles from the surface. Melting of the damaged blend resulted in reorganization of the particles at the wax-air interface, restoring the initial structure and thus the ultrahydrophobic behavior.
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Affiliation(s)
- Nikolay Puretskiy
- Leibniz Institute of Polymer Research Dresden, Hohe Str. 6, D-01069 Dresden, Germany
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Stoychev G, Kierdaszuk B, Shugar D. Interaction of Escherichia coli purine nucleoside phosphorylase (PNP) with the cationic and zwitterionic forms of the fluorescent substrate N(7)-methylguanosine. Biochim Biophys Acta 2001; 1544:74-88. [PMID: 11341918 DOI: 10.1016/s0167-4838(00)00206-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Steady-state and time-resolved fluorescence spectroscopy, and enzyme kinetics, were applied to study the reaction of purine nucleoside phosphorylase (PNP) from Escherichia coli with its substrate N(7)-methylguanosine (m7Guo), which consists of an equilibrium mixture of cationic and zwitterionic forms (pK(a)=7.0), each with characteristic absorption and fluorescence spectra, over the pH range 6-9, where absorption and intrinsic fluorescence of the enzyme are virtually unchanged. The pH-dependence of kinetic constants for phosphorolysis of m7Guo were studied under condition where the population of the zwitterion varied from 10% to 100%. This demonstrated that, whereas the zwitterion is a 3- to 6-fold poorer substrate, if at all, than the cation for the mammalian enzymes, both ionic species are almost equally good substrates for E. coli PNP. The imidazole-ring-opened form of m7Guo is neither a substrate nor an inhibitor of phosphorolysis. Enzyme fluorescence quenching, and concomitant changes in absorption and fluorescence spectra of the two ionic species of m7Guo on binding, showed that both forms are bound by the enzyme, the affinity of the zwitterion being 3-fold lower than that of the cation. Binding of m7Guo is bimodal, i.e., an increase in ligand concentration leads to a decrease in the association constant of the enzyme-ligand complex, typical for negative cooperativity of enzyme-ligand binding, with a Hill constant <1. This is in striking contrast to interaction of the enzyme with the parent Guo, for which the association constant is independent of concentration. The weakly fluorescent N(7)-methylguanine (m7Gua), the product of phosphorolysis of m7Guo, is a competitive non-substrate inhibitor of phosphorolysis (K(i)=8+/-2 microM) and exhibits negative cooperativity on binding to the enzyme at pH 6.9. Quenching of enzyme emission by the ligands is a static process, inasmuch as the mean excited-state lifetime, <tau>=2.7 ns, is unchanged in the presence of the ligands, and the constants K(SV) may therefore be considered as the association constants for the enzyme-ligand complexes. In the pH range 9.5-11 there is an instantaneous reversible decrease in PNP emission of approximately 15%, corresponding to one of the six tyrosine residues per subunit readily accessible to solvent, and OH- ions. Relevance of the overall results to the mechanism of phosphorolysis, and binding of substrates/inhibitors is discussed.
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Affiliation(s)
- G Stoychev
- Department of Biophysics, Institute of Experimental Physics, University of Warsaw, Poland
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