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Polanowski P, Hałagan K, Sikorski A. Star Polymers vs. Dendrimers: Studies of the Synthesis Based on Computer Simulations. Polymers (Basel) 2022; 14:2522. [PMID: 35808567 PMCID: PMC9269100 DOI: 10.3390/polym14132522] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Revised: 06/18/2022] [Accepted: 06/19/2022] [Indexed: 01/24/2023] Open
Abstract
A generic model was developed for studies of the polymerization process of regular branched macromolecules. Monte Carlo simulations were performed employing the Dynamic Lattice Liquid algorithm to study this process. A core-first methodology was used in a living polymerization of stars with up to 32 arms, and dendrimers consisted of 4-functional segments. The kinetics of the synthesis process for stars with different numbers of branches and dendrimers was compared. The size and structure of star-branched polymers and dendrimers during the synthesis were studied. The influence of the functionality of well-defined cores on the structure and on the dispersity of the system was also examined. The differences in the kinetics in the formation of both architectures, as well as changes to their structures, were described and discussed.
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Affiliation(s)
- Piotr Polanowski
- Department of Molecular Physics, Lodz University of Technology, 90-924 Lodz, Poland; (P.P.); (K.H.)
| | - Krzysztof Hałagan
- Department of Molecular Physics, Lodz University of Technology, 90-924 Lodz, Poland; (P.P.); (K.H.)
| | - Andrzej Sikorski
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
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2
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Kolker J, Harrer J, Ciarella S, Rey M, Ickler M, Janssen LMC, Vogel N, Löwen H. Interface-induced hysteretic volume phase transition of microgels: simulation and experiment. SOFT MATTER 2021; 17:5581-5589. [PMID: 33988219 DOI: 10.1039/d1sm00111f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Thermo-responsive microgel particles can exhibit a drastic volume shrinkage upon increasing the solvent temperature. Recently we found that the spreading of poly(N-isopropylacrylamide) (PNiPAm) microgels at a liquid interface under the influence of surface tension hinders the temperature-induced volume phase transition. In addition, we observed a hysteresis behavior upon temperature cycling, i.e. a different evolution in microgel size and shape depending on whether the microgel was initially adsorbed to the interface in expanded or collapsed state. Here, we model the volume phase transition of such microgels at an air/water interface by monomer-resolved Brownian dynamics simulations and compare the observed behavior with experiments. We reproduce the experimentally observed hysteresis in the microgel dimensions upon temperature variation. Our simulations did not observe any hysteresis for microgels dispersed in the bulk liquid, suggesting that it results from the distinct interfacial morphology of the microgel adsorbed at the liquid interface. An initially collapsed microgel brought to the interface and subjected to subsequent swelling and collapsing (resp. cooling and heating) will end up in a larger size than it had in the original collapsed state. Further temperature cycling, however, only shows a much reduced hysteresis, in agreement with our experimental observations. We attribute the hysteretic behavior to a kinetically trapped initial collapsed configuration, which relaxes upon expanding in the swollen state. We find a similar behavior for linear PNiPAm chains adsorbed to an interface. Our combined experimental - simulation investigation provides new insights into the volume phase transition of PNiPAm materials adsorbed to liquid interfaces.
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Affiliation(s)
- Jannis Kolker
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany.
| | - Johannes Harrer
- Institute of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany.
| | - Simone Ciarella
- Soft Matter and Biological Physics, Department of Applied Physics, Eindhoven University of Technology, P. O. Box 513, 5600MB Eindhoven, The Netherlands
| | - Marcel Rey
- Institute of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany.
| | - Maret Ickler
- Institute of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany.
| | - Liesbeth M C Janssen
- Soft Matter and Biological Physics, Department of Applied Physics, Eindhoven University of Technology, P. O. Box 513, 5600MB Eindhoven, The Netherlands
| | - Nicolas Vogel
- Institute of Particle Technology, Friedrich-Alexander University Erlangen-Nürnberg, Cauerstrasse 4, 91058 Erlangen, Germany.
| | - Hartmut Löwen
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, Universitätsstrasse 1, D-40225 Düsseldorf, Germany.
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3
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Boldyrev K, Chernyak A, Meshkov I, Muzafarov A, Tatarinova E, Vasil'ev S. The self-diffusion of polymethylsilsesquioxane (PMSSO) dendrimers in diluted solutions and melts. SOFT MATTER 2020; 16:9712-9725. [PMID: 32996536 DOI: 10.1039/d0sm01183e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Recently developed non-functional derivatives of polymethylsilsesquioxane (PMSSO) dendrimers of the first to fifth generation were characterized by 1H, 13C and 29Si NMR spectroscopy. The self-diffusion and NMR relaxation of PMSSO dendrimers in dilute solutions of toluene and melts were investigated in a wide temperature range (-50-80 °C). The hydrodynamic radii of dendrimers were determined from the self-diffusion coefficients measured in diluted solutions according to the Stokes-Einstein equation. The hydrodynamic radius of PMSSO dendrimers as a function of molecular mass follows a power law with the scaling exponent of 0.32 ± 0.02 in the investigated temperature range. The temperature dependences of the self-diffusion coefficients of dendrimers were described by the Arrhenius-type equation. The activation energies of self-diffusion of dendrimers in diluted toluene solutions are identical for different generations while the dependence of activation energy for dendrimers in melts shows a maximum for the third generation (G3) dendrimer. Taking into account the absence of specific interactions in PMSSO dendrimer melts the observed behavior was ascribed to the manifestation of interpenetration of dendrimer molecules. For low generations (G1 and G2) the short length of the branches does not considerably affect the translational diffusion while for higher generations (G4 and G5) the densification of the structure prevents significant interpenetration.
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Affiliation(s)
- Konstantin Boldyrev
- N.S. Enikolopov Institute of Synthetic Polymeric Materials of Russian Academy of Sciences, Profsoyuznaya st. 70, 117393 Moscow, Russia
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4
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Gupta S, Biswas P. Conformations of poly(propylene imine) dendrimers in an ionic liquid at different pH. SOFT MATTER 2020; 16:8400-8411. [PMID: 32808623 DOI: 10.1039/d0sm01026j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The conformational behavior of poly(propylene imine) (PPI) dendrimers at three different solution pH is studied in an ionic liquid (IL) solvent, 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), through molecular dynamics (MD) simulations. The size, shape, density distribution, structure factor, and the scattering intensity are evaluated to probe the conformational transition of dendrimers as a function of pH. The results of the radial atomic and terminal amine group density distribution at low pH indicate a shift in the density towards the periphery of the dendrimers due to the electrostatic repulsion between the charged tertiary amine groups within the dendrimers. The [BMIM] cations are not encapsulated within dendrimers and predominantly reside near the periphery. The extensive back-folding of the outer branches due to the electrostatic repulsion between the solvent cations and the peripheral charged amine groups at neutral and low pH results in a dense compact structure in [BMIM]Cl as compared to that in water, as evident from the results of the structure factor and scattering intensity. The structural analysis in terms of the fractal dimension reveals that the lower generation dendrimers exhibit conformational transition as a function of pH, while the higher generations exhibit a highly compact structure at all solution pH. However, PPI dendrimers at low pH exhibit more free volume as compared to that at high pH, which may be utilized to accommodate specific guest molecules.
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Affiliation(s)
- Shilpa Gupta
- Department of Chemistry, University of Delhi, Delhi-110007, India.
| | - Parbati Biswas
- Department of Chemistry, University of Delhi, Delhi-110007, India.
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5
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Gupta S, Biswas P. Orientational Relaxation of Poly(propylene imine) Dendrimers at Different pH. J Phys Chem B 2020; 124:4193-4202. [PMID: 32319292 DOI: 10.1021/acs.jpcb.0c00536] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The dilute solution dynamics of poly(propylene imine) (PPI) dendrimers is investigated at three different solution pH through molecular dynamics (MD) simulations. The dynamics of PPI dendrimers is characterized by both global and local relaxations that occur at different time and length scales. While the global dynamics may be described in terms of rotational diffusion, the local motion may be characterized through orientational relaxation dynamics measured in terms of the time autocorrelation function (ACF), second-order orientational ACF, and the spin-lattice relaxation rate. The global motion of dendrimers decreases with an increase in the size from high pH to low pH with increasing generations of growth. The results reveal that the segments at low pH relax faster than those at high pH, and the local mobility of the segments near the periphery is higher than the core segments. This observation is also evident from the spectral density and spin-lattice relaxation rate. High values of the spectral density at higher frequencies imply higher segmental mobility of the dendrimer at low pH relative to that at high pH. A shift in the maximum of the spin-lattice relaxation rate toward lower frequencies with decreasing generations indicates the dependence of local mobility on the topological distance of the segment from the periphery at all pH conditions.
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Affiliation(s)
- Shilpa Gupta
- Department of Chemistry, University of Delhi, Delhi 110007, India
| | - Parbati Biswas
- Department of Chemistry, University of Delhi, Delhi 110007, India
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6
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Zhang Y, Chapman WG. Modeling Lower Critical Solution Temperature Behavior of Associating Dendrimers Using Density Functional Theory. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:10808-10817. [PMID: 31335155 DOI: 10.1021/acs.langmuir.9b00514] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We study the phase behavior of associating dendrimers in explicit solvents using classical density functional theory. The existence of association enables uptake of solvent inside the dendrimer even for unfavorable Lennard-Jones interaction between the solvent and dendrimer. Depending on the distributions of associating sites, the dendrimer conformation can be either dense-core or dense-shell. The conformation of the associating dendrimer is greatly affected by the temperature. Due to the interplay between association interaction and Lennard-Jones attractions, we find the lower critical solution temperature (LCST) behavior of dendrimer conformation and study how it changes as the dendrimer size or solvent size changes. The dendrimer in our study displays no LCST behavior at low generations, and it has a maximum LCST at G4. Moreover, increasing the solvent chain length decreases the LCST. For solvents with self-association, the competition between solvent-solvent association and solvent-dendrimer association also tends to reduce the LCST. Qualitatively consistent with experiments, our results provide insight into the molecular mechanism of the LCST behavior of associating dendrimers.
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Affiliation(s)
- Yuchong Zhang
- Department of Chemical and Biomolecular Engineering , Rice University , 6100 Main Street , Houston , Texas 77005 , United States
| | - Walter G Chapman
- Department of Chemical and Biomolecular Engineering , Rice University , 6100 Main Street , Houston , Texas 77005 , United States
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7
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Gupta S, Biswas P. Effect of pH on Size and Internal Structure of Poly(propylene imine) Dendrimers: A Molecular Dynamics Simulation Study. J Phys Chem B 2018; 122:9250-9263. [PMID: 30199254 DOI: 10.1021/acs.jpcb.8b04653] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The behavior of poly(propylene imine) dendrimers at three different solution pH is investigated through molecular dynamics (MD) simulations in explicit solvent. MD simulations provide an insight into the conformational properties of dendrimers via the evaluation of their size, shape, radial density distribution, static structure factor, and scattering intensity. The size of the dendrimer increases from high solution pH to low pH. The internal structure of the dendrimer is quantified in terms of the radial atomic density profile and the terminal amine group density distribution. While the radial atomic density distribution shifts away from the core of the dendrimer with decreasing pH, a significant degree of back-folding of the outer generations is observed at high pH for higher generations of growth. Results from the structure factor and scattering intensity indicate two types of conformational transitions: (i) as a function of the solution pH, where the dendrimer evolves from an expanded structure at low pH to a highly compact one at high pH (except for higher generations), and (ii) with increasing generations, where the open structure of the dendrimer at lower generations transforms to a compact structure at higher generations at both high and low pH, characterized by a change in the fractal dimension.
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Affiliation(s)
- Shilpa Gupta
- Department of Chemistry , University of Delhi , Delhi 110007 , India
| | - Parbati Biswas
- Department of Chemistry , University of Delhi , Delhi 110007 , India
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8
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Zhang Y, Valiya Parambathu A, Chapman WG. Density functional study of dendrimer molecules in solvents of varying quality. J Chem Phys 2018; 149:064904. [PMID: 30111128 DOI: 10.1063/1.5035423] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Modified inhomogeneous statistical associating fluid theory (iSAFT) density functional theory is extended to dendrimer molecules in solvents of varying quality. The detailed structures of isolated dendrimers in implicit solvent are calculated and have a semi-quantitative agreement with simulation results available in the literature. The dendrimers form dense-core structures under all conditions, while their radius of gyration follows different scaling laws. Factors that affect the quality of the solvent are systematically studied in the explicit solvent case. It is found that the solvent size, density, chemical affinity and temperature all play a role in determining a solvent to be good or poor. New molecular dynamics simulations are performed to validate the iSAFT results. Our results provide insight into the phase behavior of dendrimer solutions as well as guidance in practical applications.
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Affiliation(s)
- Yuchong Zhang
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, USA
| | - Arjun Valiya Parambathu
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, USA
| | - Walter G Chapman
- Department of Chemical and Biomolecular Engineering, Rice University, Houston, Texas 77005-1892, USA
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9
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Effect of an asymmetry of branching on structural characteristics of dendrimers revealed by Brownian dynamics simulations. POLYMER 2018. [DOI: 10.1016/j.polymer.2018.04.055] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Nikam R, Xu X, Ballauff M, Kanduč M, Dzubiella J. Charge and hydration structure of dendritic polyelectrolytes: molecular simulations of polyglycerol sulphate. SOFT MATTER 2018; 14:4300-4310. [PMID: 29780980 PMCID: PMC5977385 DOI: 10.1039/c8sm00714d] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 05/09/2018] [Indexed: 06/08/2023]
Abstract
Macromolecules based on dendritic or hyperbranched polyelectrolytes have been emerging as high potential candidates for biomedical applications. Here we study the charge and solvation structure of dendritic polyglycerol sulphate (dPGS) of generations 0 to 3 in aqueous sodium chloride solution by explicit-solvent molecular dynamics computer simulations. We characterize dPGS by calculating several important properties such as relevant dPGS radii, molecular distributions, the solvent accessible surface area, and the partial molecular volume. In particular, as the dPGS exhibits high charge renormalization effects, we address the challenges of how to obtain a well-defined effective charge and surface potential of dPGS for practical applications. We compare implicit- and explicit-solvent approaches in our all-atom simulations with the coarse-grained simulations from our previous work. We find consistent values for the effective electrostatic size (i.e., the location of the effective charge of a Debye-Hückel sphere) within all the approaches, deviating at most by the size of a water molecule. Finally, the excess chemical potential of water insertion into dPGS and its thermodynamic signature are presented and rationalized.
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Affiliation(s)
- Rohit Nikam
- Research Group Simulations of Energy Materials
, Helmholtz-Zentrum Berlin für Materialien und Energie
,
Hahn-Meitner-Platz 1
, D-14109 Berlin
, Germany
.
;
- Institut für Physik
, Humboldt-Universität zu Berlin
,
Newtonstr. 15
, D-12489 Berlin
, Germany
| | - Xiao Xu
- School of Chemical Engineering
, Nanjing University of Science and Technology
,
200 Xiao Ling Wei
, Nanjing 210094
, P. R. China
| | - Matthias Ballauff
- Institut für Physik
, Humboldt-Universität zu Berlin
,
Newtonstr. 15
, D-12489 Berlin
, Germany
- Soft Matter and Functional Materials
, Helmholtz-Zentrum Berlin für Materialien und Energie
,
Hahn-Meitner-Platz 1
, D-14109 Berlin
, Germany
- Multifunctional Biomaterials for Medicine
, Helmholtz Virtual Institute
,
Kantstr. 55
, D-14513 Teltow-Seehof
, Germany
| | - Matej Kanduč
- Research Group Simulations of Energy Materials
, Helmholtz-Zentrum Berlin für Materialien und Energie
,
Hahn-Meitner-Platz 1
, D-14109 Berlin
, Germany
.
;
| | - Joachim Dzubiella
- Research Group Simulations of Energy Materials
, Helmholtz-Zentrum Berlin für Materialien und Energie
,
Hahn-Meitner-Platz 1
, D-14109 Berlin
, Germany
.
;
- Physikalisches Institut
, Albert-Ludwigs-Universität Freiburg
,
Hermann-Herder Str. 3
, D-79104 Freiburg
, Germany
.
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11
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Xu X, Ran Q, Haag R, Ballauff M, Dzubiella J. Charged Dendrimers Revisited: Effective Charge and Surface Potential of Dendritic Polyglycerol Sulfate. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00742] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Xiao Xu
- Institut
für Weiche Materie und Funktionale Materialien, Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
- Institut
für Physik, Humboldt-Universität zu Berlin, Newtonstr.
15, 12489 Berlin, Germany
- Multifunctional
Biomaterials for Medicine, Helmholtz Virtual Institute, Kantstr. 55, 14513 Teltow-Seehof, Germany
| | - Qidi Ran
- Institut
für Physik, Humboldt-Universität zu Berlin, Newtonstr.
15, 12489 Berlin, Germany
- Multifunctional
Biomaterials for Medicine, Helmholtz Virtual Institute, Kantstr. 55, 14513 Teltow-Seehof, Germany
- Institut
für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Rainer Haag
- Multifunctional
Biomaterials for Medicine, Helmholtz Virtual Institute, Kantstr. 55, 14513 Teltow-Seehof, Germany
- Institut
für Chemie und Biochemie, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany
| | - Matthias Ballauff
- Institut
für Weiche Materie und Funktionale Materialien, Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
- Institut
für Physik, Humboldt-Universität zu Berlin, Newtonstr.
15, 12489 Berlin, Germany
- Multifunctional
Biomaterials for Medicine, Helmholtz Virtual Institute, Kantstr. 55, 14513 Teltow-Seehof, Germany
| | - Joachim Dzubiella
- Institut
für Weiche Materie und Funktionale Materialien, Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
- Institut
für Physik, Humboldt-Universität zu Berlin, Newtonstr.
15, 12489 Berlin, Germany
- Multifunctional
Biomaterials for Medicine, Helmholtz Virtual Institute, Kantstr. 55, 14513 Teltow-Seehof, Germany
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12
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Rai GJ, Biswas P. Topology driven structural transition of dendrimers with a dimensional cross-over. POLYMER 2017. [DOI: 10.1016/j.polymer.2017.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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13
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Balabaev NK, Mazo MA, Kramarenko EY. Insight into the Structure of Polybutylcarbosilane Dendrimer Melts via Extensive Molecular Dynamics Simulations. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01639] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- N. K. Balabaev
- Institute
of Mathematical Problems of Biology, Keldysh Institute of Applied Mathematics RAS, Pushchino, Moscow Region 142290, Russia
| | - M. A. Mazo
- Semenov Institute
of Chemical Physics RAS, Moscow 119991, Russia
| | - E. Yu. Kramarenko
- Faculty
of Physics, Lomonosov Moscow State University, Moscow 119991, Russia
- A.N. Nesmeyanov
Institute for Organoelement Compounds RAS, Moscow 119991, Russia
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14
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Wengenmayr M, Dockhorn R, Sommer JU. Multicore Unimolecular Structure Formation in Single Dendritic–Linear Copolymers under Selective Solvent Conditions. Macromolecules 2016. [DOI: 10.1021/acs.macromol.6b01712] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Martin Wengenmayr
- Leibniz Institute
of Polymer Research Dresden, Hohe Strasse
6, 01069 Dresden, Germany
- Institute
for Theoretical Physics, Technische Universität Dresden, 01069 Dresden, Germany
| | - Ron Dockhorn
- Leibniz Institute
of Polymer Research Dresden, Hohe Strasse
6, 01069 Dresden, Germany
- Institute
for Theoretical Physics, Technische Universität Dresden, 01069 Dresden, Germany
| | - Jens-Uwe Sommer
- Leibniz Institute
of Polymer Research Dresden, Hohe Strasse
6, 01069 Dresden, Germany
- Institute
for Theoretical Physics, Technische Universität Dresden, 01069 Dresden, Germany
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15
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Chen C, Tang P, Qiu F, Shi AC. Density Functional Study for Homodendrimers and Amphiphilic Dendrimers. J Phys Chem B 2016; 120:5553-63. [DOI: 10.1021/acs.jpcb.6b03005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Cangyi Chen
- The
State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory
of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Ping Tang
- The
State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory
of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - Feng Qiu
- The
State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory
of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China
| | - An-Chang Shi
- Department
of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada L8S 4M1
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16
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Rabbel H, Frey H, Schmid F. Statistical properties of linear-hyperbranched graft copolymers prepared via “hypergrafting” of ABm monomers from linear B-functional core chains: A molecular dynamics simulation. J Chem Phys 2015; 143:243125. [DOI: 10.1063/1.4935371] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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17
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Chong L, Aydin F, Dutt M. Implicit solvent coarse-grained model of polyamidoamine dendrimers: Role of generation and pH. J Comput Chem 2015; 37:920-6. [PMID: 26676461 DOI: 10.1002/jcc.24277] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Revised: 10/24/2015] [Accepted: 11/08/2015] [Indexed: 01/18/2023]
Abstract
Highly branched polymers such as polyamidoamine (PAMAM) dendrimers are promising macromolecules in the realm of nanobiotechnology due to their high surface coverage of tunable functional groups. Modeling efforts of PAMAM can provide structural and morphological properties, but the inclusion of solvents and the exponential growth of atoms with generations make atomistic simulations computationally expensive. We apply an implicit solvent coarse-grained model, called the Dry Martini force field, to PAMAM dendrimers. The reduced number of particles and the absence of a solvent allow the capture of longer spatiotemporal scales. This study characterizes PAMAM dendrimers of generations one through seven in acidic, neutral, and basic pH environments. Comparison with existing literature, both experimental and theoretical, is done using measurements of the radius of gyration, moment of inertia, radial distributions, and scaling exponents. Additionally, ion coordination distributions are studied to provide insight into the effects of interior and exterior protonation on counter ions. This model serves as a starting point for future designs of larger functionalized dendrimers.
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Affiliation(s)
- Leebyn Chong
- Department of Chemical and Biochemical Engineering, Rutgers the State University of New Jersey, Piscataway, New Jersey, 08854
| | - Fikret Aydin
- Department of Chemical and Biochemical Engineering, Rutgers the State University of New Jersey, Piscataway, New Jersey, 08854
| | - Meenakshi Dutt
- Department of Chemical and Biochemical Engineering, Rutgers the State University of New Jersey, Piscataway, New Jersey, 08854
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18
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Smeijers A, Markvoort A, Pieterse K, Hilbers P. Coarse-grained modelling of urea-adamantyl functionalised poly(propylene imine) dendrimers. MOLECULAR SIMULATION 2015. [DOI: 10.1080/08927022.2015.1096359] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- A.F. Smeijers
- Computational Biology, Department of Biomedical Engineering, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
| | - A.J. Markvoort
- Computational Biology, Department of Biomedical Engineering, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
- Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
| | - K. Pieterse
- Computational Biology, Department of Biomedical Engineering, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
- Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
| | - P.A.J. Hilbers
- Computational Biology, Department of Biomedical Engineering, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
- Institute for Complex Molecular Systems, Technische Universiteit Eindhoven, Eindhoven, the Netherlands
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19
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Wawrzyńska E, Sikorski A, Zifferer G. Monte Carlo Simulation Studies of Regular and Irregular Dendritic Polymers. MACROMOL THEOR SIMUL 2015. [DOI: 10.1002/mats.201500036] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Edyta Wawrzyńska
- Department of Physical Chemistry; University of Vienna; Währinger Str. 42 A-1090 Vienna Austria
- Faculty of Chemistry; Warsaw University of Technology; Noakowskiego 3 00-664 Warsaw Poland
- Faculty of Chemistry; University of Warsaw; Pasteura 1 02-093 Warsaw Poland
| | - Andrzej Sikorski
- Faculty of Chemistry; University of Warsaw; Pasteura 1 02-093 Warsaw Poland
| | - Gerhard Zifferer
- Department of Physical Chemistry; University of Vienna; Währinger Str. 42 A-1090 Vienna Austria
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20
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Rubio AM, McBride C, Freire JJ. Binary Interactions between Dendrimer Molecules. A Simulation Study. Macromolecules 2014. [DOI: 10.1021/ma501127f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ana M. Rubio
- Departamento
de Química Física, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain
| | - Carl McBride
- Departamento
de Ciencias y Técnicas Fisicoquímicas, Facultad de Ciencias, Universidad Nacional de Educación a Distancia (UNED), Paseo Senda del
Rey 9, 28040 Madrid, Spain
| | - Juan J. Freire
- Departamento
de Ciencias y Técnicas Fisicoquímicas, Facultad de Ciencias, Universidad Nacional de Educación a Distancia (UNED), Paseo Senda del
Rey 9, 28040 Madrid, Spain
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21
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Wawrzyńska E, Eisenhaber S, Parzuchowski P, Sikorski A, Zifferer G. Monte Carlo Simulation Studies of the Size and Shape of Regular Three Generation Dendrimers. MACROMOL THEOR SIMUL 2014. [DOI: 10.1002/mats.201300159] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Edyta Wawrzyńska
- Department of Physical Chemistry; University of Vienna; Währinger Str. 42 A-1090 Vienna Austria
- Department of Chemistry; Warsaw University of Technology; Noakowskiego 3 00-664 Warsaw Poland
- Department of Chemistry; University of Warsaw; Pasteura 1 02-093 Warsaw Poland
| | - Stephan Eisenhaber
- Department of Physical Chemistry; University of Vienna; Währinger Str. 42 A-1090 Vienna Austria
| | - Paweł Parzuchowski
- Department of Chemistry; Warsaw University of Technology; Noakowskiego 3 00-664 Warsaw Poland
| | - Andrzej Sikorski
- Department of Chemistry; University of Warsaw; Pasteura 1 02-093 Warsaw Poland
| | - Gerhard Zifferer
- Department of Physical Chemistry; University of Vienna; Währinger Str. 42 A-1090 Vienna Austria
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22
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Kłos JS, Sommer JU. Coarse grained simulations of neutral and charged dendrimers. POLYMER SCIENCE SERIES C 2013. [DOI: 10.1134/s1811238213070023] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Kłos JS, Sommer JU. Simulations of Neutral and Charged Dendrimers in Solvents of Varying Quality. Macromolecules 2013. [DOI: 10.1021/ma4001989] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- J. S. Kłos
- Leibniz Institute of Polymer Research Dresden e.V., 01069 Dresden, Germany
- Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznań,
Poland
| | - J.-U. Sommer
- Leibniz Institute of Polymer Research Dresden e.V., 01069 Dresden, Germany
- Institute for Theoretical Physics, Technische Universität Dresden, 01069 Dresden,
Germany
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24
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Sebby KB, Walter ED, Usselman RJ, Cloninger MJ, Singel DJ. End-group distributions of multiple generations of spin-labeled PAMAM dendrimers. J Phys Chem B 2011; 115:4613-20. [PMID: 21469686 PMCID: PMC3424105 DOI: 10.1021/jp112390d] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dendrimers are attractive templates to display functional molecular components. Since the behavior of dendrimer systems can depend greatly on the accessibility of these molecular components to the external environment, and on the spatial arrangement of functional groups attached to the dendrimer terminal branches (end-groups), techniques to determine the locations of end-groups are highly desirable. In this report, we describe a method to analyze the EPR spectra of multiple generations of poly(amidoamine) (PAMAM) dendrimers which have spin-labels attached to end-groups in variable percentages of the total number of available sites. The spectra are treated as a convolution of a narrow spin-label spectrum and a variable line broadening function. Trends in the parameters that describe the best-fit line broadening function with spin-label loading reveal the spatial arrangements and homogeneity of spin environments of the labels. We observe a shift in the end-group distribution from generation 3 (G(3)) to G(4) dendrimers that indicates a change in morphology from an open, extended structure to a more dense, compact arrangement.
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Affiliation(s)
- Karl B Sebby
- Department of Chemistry and Biochemistry, Montana State University, Bozeman, Montana 59717, United States.
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25
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Affiliation(s)
- Jaroslaw T. Bosko
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
| | - J. Ravi Prakash
- Department of Chemical Engineering, Monash University, Melbourne, Victoria 3800, Australia
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26
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Carbone P, Lue L. Prediction of Bulk Density and Molecular Packing in Model Dendrimers with Different Chain Stiffness. Macromolecules 2010. [DOI: 10.1021/ma1020402] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Paola Carbone
- School of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, M13 9PL, United Kingdom
| | - Leo Lue
- Department of Chemical and Process Engineering, University of Strathclyde, James Weir Building, 75 Montrose Street, Glasgow G1 1XJ, United Kingdom
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27
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Kröger M, Peleg O, Halperin A. From Dendrimers to Dendronized Polymers and Forests: Scaling Theory and its Limitations. Macromolecules 2010. [DOI: 10.1021/ma100861b] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Martin Kröger
- Polymer Physics, ETH Zürich, Department of Materials, CH-8093 Zürich, Switzerland
| | - Orit Peleg
- Polymer Physics, ETH Zürich, Department of Materials, CH-8093 Zürich, Switzerland
| | - Avraham Halperin
- Laboratoire de Spectrométrie Physique (LSP) CNRS UniVersité Joseph Fourier, BP 87, 38402 Saint Martin d’Hères cedex, France
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28
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Affiliation(s)
- Paul M. Welch
- Theoretical Division and Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
| | - Cynthia F. Welch
- Theoretical Division and Materials Science and Technology Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545
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29
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Roberts BP, Scanlon MJ, Krippner GY, Chalmers DK. Molecular Dynamics of Poly(l-lysine) Dendrimers with Naphthalene Disulfonate Caps. Macromolecules 2009. [DOI: 10.1021/ma802154e] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Benjamin P. Roberts
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia, and Verva Pharmaceuticals Ltd., P.O. Box 1069, Grovedale, Victoria 3216, Australia
| | - Martin J. Scanlon
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia, and Verva Pharmaceuticals Ltd., P.O. Box 1069, Grovedale, Victoria 3216, Australia
| | - Guy Y. Krippner
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia, and Verva Pharmaceuticals Ltd., P.O. Box 1069, Grovedale, Victoria 3216, Australia
| | - David K. Chalmers
- Medicinal Chemistry and Drug Action, Monash Institute of Pharmaceutical Sciences, 381 Royal Parade, Parkville, Victoria 3052, Australia, and Verva Pharmaceuticals Ltd., P.O. Box 1069, Grovedale, Victoria 3216, Australia
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30
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Bosko JT, Ravi Prakash J. Effect of molecular topology on the transport properties of dendrimers in dilute solution at Θ temperature: A Brownian dynamics study. J Chem Phys 2008; 128:034902. [DOI: 10.1063/1.2823034] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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31
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Newkome GR, Shreiner CD. Poly(amidoamine), polypropylenimine, and related dendrimers and dendrons possessing different 1→2 branching motifs: An overview of the divergent procedures. POLYMER 2008. [DOI: 10.1016/j.polymer.2007.10.021] [Citation(s) in RCA: 313] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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32
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Lin Y, Liao Q, Jin X. Molecular Dynamics Simulations of Dendritic Polyelectrolytes with Flexible Spacers in Salt Free Solution. J Phys Chem B 2007; 111:5819-28. [PMID: 17488000 DOI: 10.1021/jp070514l] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We present the results of molecular dynamics simulations of dendritic polyelectrolytes in dilute salt-free solutions. The dendritic polyelectrolytes are modeled as an ensemble of regular-branched bead-spring chains of neutral and charged Lennard-Jones particles with explicit counterions. A wide range of molecular variables of the dendritic polyelectrolytes such as generation number, spacer length, and charge density were considered in the simulations. The effect of dendrimer size on relaxation time, the conformation of spacers, and the size dependence of the dendrimer on molecular variables are discussed and compared with a Flory type theory. The osmotic coefficients of the dilute dendritic polyelectrolyte solutions, as well as the profiles of monomers and counterions, are calculated directly from the simulations. Our simulation results show that the inner spacers of the dendrimers are extensively stretched, and the size dependence on the molecular weight deviates from the scaling prediction that assumes a Gaussian elasticity of the spacer.
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Affiliation(s)
- Yong Lin
- State Key Laboratory of Polymer Physics and Chemistry, Joint Laboratory of Polymer Science and Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China
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33
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Kosmas M, Vlahos C, Avgeropoulos A. A theoretical study of conformational properties of dendritic block copolymers of first generation. J Chem Phys 2006; 125:094908. [PMID: 16965120 DOI: 10.1063/1.2337625] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Conformational properties of a dendritic block copolymer of the first generation are studied by means of an analytic calculation and dimensionality techniques. The polymer can have different functionalities and branch lengths in the interior region and the exterior shell. Three parameters are included in order to describe the intensity of the interactions between the same or different monomeric units. Based on the average end to end distances of the branches effective angles are defined in order to study how the microscopic parameters control the position and activity of the end groups, but also the hollowness in the internal region and the tweezing ability of the external shell of the macromolecule.
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Affiliation(s)
- M Kosmas
- Department of Chemistry, University of Ioannina, 45110 Ioannina, Greece.
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34
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Affiliation(s)
- Tong Zhou
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576, Republic of Singapore
| | - Shing Bor Chen
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576, Republic of Singapore
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35
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Suek NW, Lamm MH. Effect of Terminal Group Modification on the Solution Properties of Dendrimers: A Molecular Dynamics Simulation Study. Macromolecules 2006. [DOI: 10.1021/ma060177z] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nicholas W. Suek
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011
| | - Monica H. Lamm
- Department of Chemical and Biological Engineering, Iowa State University, Ames, Iowa 50011
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36
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Fritzinger B, Appelhans D, Voit B, Scheler U. Core Functionality and Scaling Behavior of Lysine Dendrimers. Macromol Rapid Commun 2005. [DOI: 10.1002/marc.200500320] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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37
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Freire JJ, Rodríguez E, Rubio AM. Monte Carlo calculations for the intrinsic viscosity of several dendrimer molecules. J Chem Phys 2005; 123:154901. [PMID: 16252966 DOI: 10.1063/1.2056546] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have performed Monte Carlo simulations to reproduce the intrinsic viscosity corresponding to different generation of several types of dendrite molecules: polyamidoamine dendrimers with an ethylendiamine core, polypropylene-imine with a diaminobutane core, and monodendrons and tridendrons of polybenzylether. With this end, we have employed coarse-grained idealizations of the molecules constituted by only two beads in each repeat unit (one in a branching or end unit and one intermediate along the repeat unit) and a simple hard-sphere potential between non-neighboring beads. Our goal is to investigate if this simple model is able to provide a reasonable description of some differences between these systems that have been observed experimentally, in particular, the location of the maximum in the intrinsic viscosity as a function of the generation number. Experimental radii of gyration in a given solvent are reproduced by a fit of the hard-sphere potential diameter. Subsequently, intrinsic viscosities are calculated by the variational approach of Fixman, which yields an accurate lower-bound value with an additional hydrodynamic interaction parameter (the friction radius of the beads). The results show a pronounced variation of the maximum location with the value of the friction radius and the structural details that cannot be mimicked with simpler models. The initial conformations for the Monte Carlo procedure are taken from atomistic configurations thermalized by means of a molecular dynamics.
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Affiliation(s)
- Juan J Freire
- Departamento de Ciencias y Técnicas Fisicoquímicas, Facultad de Ciencias, Universidad Nacional de Educación a Distancia (UNED), Senda del Rey 9, 28040 Madrid, Spain.
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38
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Affiliation(s)
- Tong Zhou
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576
| | - Shing Bor Chen
- Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117576
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39
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Giupponi G, Buzza DMA. A Monte Carlo study of amphiphilic dendrimers: Spontaneous asymmetry and dendron separation. J Chem Phys 2005; 122:194903. [PMID: 16161613 DOI: 10.1063/1.1896347] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We study via Monte Carlo simulation the conformation of amphiphilic dendrimers for which terminal monomers (t) and internal monomers (i) interact differently with the solvent (s). Specifically, we have studied g = 3,6 dendrimers as a function of chi(it), chi(is), and chi(ts) (chi is the differential contact energy between the different particles) for parameter values chi(it) = 0, +/-1 and -1 < chi(is), chi(ts) < 1. We have allowed negative chi values in order to model attractive polar interactions (e.g., hydrogen bonding) which are believed to be important in many dendrimer/solvent systems. We find the "phase diagram" of dendrimer conformations to be extremely rich and to be a strong function of g, chi(is), and chi(ts) but only a weak function of chi(it), For chi(is), chi(ts) > 0, we observe dendrimer conformations, such as unimolecular normal micelles and inverted loopy micelles. However, for chi(is) < 0 or chi(ts) < 0, we observe more exotic molecular conformations, for example, the spontaneous development of asymmetry and dendron separation. These properties are analyzed in terms of snapshots as well as more quantitatively in terms of the radii of gyration, radial density profiles, pair-correlation functions, degree of asymmetry, and dendron overlap factor. By exploiting the dramatic conformational changes under different solvent conditions, we suggest the possibility of using amphiphilic dendrimers as stimuli-responsive smart materials.
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Affiliation(s)
- G Giupponi
- Interdisciplinary Research Center (IRC) in Polymer Science and Technology, School of Physics and Astronomy, University of Leeds, Leeds LS2 9JT, United Kingdom.
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