1
|
Bera A, Sahoo S, Thakur S, Das SK. Active particles in explicit solvent: Dynamics of clustering for alignment interaction. Phys Rev E 2022; 105:014606. [PMID: 35193229 DOI: 10.1103/physreve.105.014606] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
We study the dynamics of clustering in systems containing active particles that are immersed in an explicit solvent. For this, we have adopted a hybrid simulation method, consisting of molecular dynamics and multiparticle collision dynamics. In our model, the overlap-avoiding passive interaction of an active particle with another active particle or a solvent particle has been taken care of via variants of the Lennard-Jones potential. Dynamic interactions among the active particles have been incorporated via a Vicsek-like alignment rule in self-propulsion that facilitates clustering. We quantify the effects of activity and importance of hydrodynamics on the dynamics of clustering via variations of relevant system parameters. Results are obtained for low overall density of active particles, for which the state point is close to the vapor branch of the coexistence curve, and thus the morphology consists of disconnected clusters. In such a situation, the mechanism of growth switches among particle diffusion, diffusive coalescence, and ballistic aggregation, depending upon the presence or absence of active and hydrodynamic interactions providing different kinds of mobilities to the clusters. Corresponding growth laws have been quantified and discussed in the context of appropriate theoretical pictures. Our results suggest that multiparticle collision dynamics is an effective method for the investigation of hydrodynamic phenomena in phase-separating active matter systems.
Collapse
Affiliation(s)
- Arabinda Bera
- Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560064, India
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560064, India
| | - Soudamini Sahoo
- Department of Physics, Indian Institute of Science Education and Research Bhopal, Madhya Pradesh 462066, India
| | - Snigdha Thakur
- Department of Physics, Indian Institute of Science Education and Research Bhopal, Madhya Pradesh 462066, India
| | - Subir K Das
- Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560064, India
- School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560064, India
| |
Collapse
|
2
|
Liu Y, Widmer-Cooper A. A versatile simulation method for studying phase behavior and dynamics in colloidal rod and rod-polymer suspensions. J Chem Phys 2019; 150:244508. [PMID: 31255071 DOI: 10.1063/1.5096193] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Here, we present an implicit-solvent model for dynamic simulations of hard-rod and rod-polymer suspensions. Individual rods are represented by a rigid linear chain consisting of overlapping spheres which interact through a pseudohard-core potential based on the cut-and-shifted Mie (generalized Lennard-Jones) potential with exponents (50, 49). In the rod-polymer suspensions, the polymers are modeled as freely interpenetrable spheres with respect to each other, while there is the pseudohard-core repulsion between the polymer and rod spheres. Dynamic simulations with this model are carried out with a dissipative particle dynamics (DPD) thermostat-each sphere is put in a larger DPD sphere and thus interacts with others via additional pairwise frictional and random forces-which captures the effects of Brownian forces due to the solvent while conserving local momentum. The phase behavior of these models, obtained from continuous compression and expansion simulations, reproduces previous predictions based on theoretical calculations and Monte Carlo simulations. Our method is suited to study dynamic processes in these suspensions, including nucleation and self-assembly, and can be readily extended to colloidal particles of different shapes and chemistry.
Collapse
Affiliation(s)
- Yawei Liu
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Asaph Widmer-Cooper
- ARC Centre of Excellence in Exciton Science, School of Chemistry, University of Sydney, Sydney, New South Wales 2006, Australia
| |
Collapse
|
3
|
Chen A, Zhao N, Hou Z. The effect of hydrodynamic interactions on nanoparticle diffusion in polymer solutions: a multiparticle collision dynamics study. SOFT MATTER 2017; 13:8625-8635. [PMID: 29115361 DOI: 10.1039/c7sm01854a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The diffusion of nanoparticles (NPs) in polymer solutions is studied by a combination of a mesoscale simulation method, multiparticle collision dynamics (MPCD), and molecular dynamics (MD) simulations. We investigate the long-time diffusion coefficient D as well as the subdiffusive behavior in the intermediate time region. The dependencies of both D and subdiffusion factor α on NP size and polymer concentration, respectively, are explicitly calculated. Particular attention is paid to the role of hydrodynamic interaction (HI) in the NP diffusion dynamics. Our simulation results show that the long-time diffusion coefficients satisfy perfectly the scaling relation found by experimental observations. Meanwhile, the subdiffusive factor decreases with the increase in polymer concentration but is of little relevance to the NP size. By parallel simulations with and without HI, we reveal that HI will generally enhance D, while the enhancement effect is non-monotonous with increasing polymer concentration, and it becomes most pronounced at semidilute concentrations. With the aid of a scaling law based on the diffusive activation energy model, we understand that HI affects diffusion through decreasing the diffusive activation energy on the one hand while increasing the effective diffusion size on the other. In addition, HI will certainly influence the subdiffusive behavior of the NP, leading to a larger subdiffusion exponent.
Collapse
Affiliation(s)
- Anpu Chen
- College of Chemistry, Sichuan University, Chengdu 610064, China.
| | | | | |
Collapse
|
4
|
Ruggiero F, Aruta R, Netti PA, Torino E. Confinement of a polymer chain: An entropic study by Monte Carlo method. AIChE J 2017. [DOI: 10.1002/aic.15951] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Flavia Ruggiero
- Center for Advanced Biomaterials for HealthCare; IIT@CRIB, Istituto Italiano di Tecnologia; Naples Italy
- Dept. of Chemical, Materials and Industrial Production Engineering; University of Naples Federico II; Naples Italy
| | - Rosaria Aruta
- Center for Advanced Biomaterials for HealthCare; IIT@CRIB, Istituto Italiano di Tecnologia; Naples Italy
- Dept. of Chemical, Materials and Industrial Production Engineering; University of Naples Federico II; Naples Italy
| | - Paolo Antonio Netti
- Center for Advanced Biomaterials for HealthCare; IIT@CRIB, Istituto Italiano di Tecnologia; Naples Italy
- Dept. of Chemical, Materials and Industrial Production Engineering; University of Naples Federico II; Naples Italy
- Interdisciplinary Research Center of Biomaterials, University of Naples Federico II; Naples Italy
| | - Enza Torino
- Center for Advanced Biomaterials for HealthCare; IIT@CRIB, Istituto Italiano di Tecnologia; Naples Italy
- Interdisciplinary Research Center of Biomaterials, University of Naples Federico II; Naples Italy
| |
Collapse
|
5
|
Torino E, Aruta R, Sibillano T, Giannini C, Netti PA. Synthesis of semicrystalline nanocapsular structures obtained by Thermally Induced Phase Separation in nanoconfinement. Sci Rep 2016; 6:32727. [PMID: 27604818 PMCID: PMC5015022 DOI: 10.1038/srep32727] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 08/08/2016] [Indexed: 12/18/2022] Open
Abstract
Phase separation of a polymer solution exhibits a peculiar behavior when induced in a nanoconfinement. The energetic constraints introduce additional interactions between the polymer segments that reduce the number of available configurations. In our work, this effect is exploited in a one-step strategy called nanoconfined-Thermally Induced Phase Separation (nc-TIPS) to promote the crystallization of polymer chains into nanocapsular structures of controlled size and shell thickness. This is accomplished by performing a quench step of a low-concentrated PLLA-dioxane-water solution included in emulsions of mean droplet size <500 nm acting as nanodomains. The control of nanoconfinement conditions enables not only the production of nanocapsules with a minimum mean particle diameter of 70 nm but also the tunability of shell thickness and its crystallinity degree. The specific properties of the developed nanocapsular architectures have important implications on release mechanism and loading capability of hydrophilic and lipophilic payload compounds.
Collapse
Affiliation(s)
- Enza Torino
- Center for Advanced Biomaterials for Health Care @CRIB - Istituto Italiano di Tecnologia (IIT), Largo Barsanti e Matteucci n. 53, 80125, Napoli, Italy
- University of Naples Federico II, Interdisciplinary Research Center of Biomaterials, CRIB P.le Tecchio 80, 80125, Naples, Italy
| | - Rosaria Aruta
- Center for Advanced Biomaterials for Health Care @CRIB - Istituto Italiano di Tecnologia (IIT), Largo Barsanti e Matteucci n. 53, 80125, Napoli, Italy
- University of Naples Federico II, Department of Chemical, Materials and Industrial Production Engineering, P.le Tecchio 80, 80125, Naples, Italy
| | - Teresa Sibillano
- CNR - IC Istituto di Cristallografia, via Amendola 122/O, 70126 Bari-Italia
| | - Cinzia Giannini
- CNR - IC Istituto di Cristallografia, via Amendola 122/O, 70126 Bari-Italia
| | - Paolo A. Netti
- Center for Advanced Biomaterials for Health Care @CRIB - Istituto Italiano di Tecnologia (IIT), Largo Barsanti e Matteucci n. 53, 80125, Napoli, Italy
- University of Naples Federico II, Interdisciplinary Research Center of Biomaterials, CRIB P.le Tecchio 80, 80125, Naples, Italy
- University of Naples Federico II, Department of Chemical, Materials and Industrial Production Engineering, P.le Tecchio 80, 80125, Naples, Italy
| |
Collapse
|
6
|
Koning J, Hennequin Y, Bonn D, Indekeu JO. Contact line of adsorbed colloid-polymer droplets in theory and experiment. SOFT MATTER 2016; 12:4052-4058. [PMID: 27029605 DOI: 10.1039/c5sm02978c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The contact line between the colloid-rich bulk liquid and an adsorbed thin film in colloid-polymer mixtures (CPM) is studied by means of an interface displacement model. The interface displacement profiles are compared to laser scanning confocal microscopy (LSCM) images. The mixtures consist of poly(methylmetacrylate) (PMMA) colloids and polystyrene (PS) polymers with polymer-to-colloid size ratio q = 1.18. Based on the experimental parameters, the theoretical model predicts a contact angle for colloid-rich liquid droplets adsorbed on glass of θ∞ = 59°, assuming a contact line with infinite radius, R = ∞. When a contact-line curvature correction and a correction for the protein-limit character of the CPM are taken into account, a modest shift is obtained. The refined theory predicts θ≈ 56°. The contact angle determined visually from the LSCM images is θ≈ 30°. The model predicts a three-phase contact-line tension of τ = -1.2 × 10(-12) N (uncorrected) and τ = -2.3 × 10(-13) N (with protein-limit correction), which is physically sound both in sign and magnitude. The line tension influences the contact angle to a small extent due to the contact line curvature. The predicted width of the transition zone between the thin film and the droplet is about 2 μm. The effect of gravity is noticeable as a deformation near the middle of the droplet.
Collapse
Affiliation(s)
- Jesper Koning
- Instituut voor Theoretische Fysica, KU Leuven, Celestijnenlaan 200D, B-3001 Leuven, Belgium.
| | | | | | | |
Collapse
|
7
|
Trefz B, Das SK, Egorov SA, Virnau P, Binder K. Activity mediated phase separation: Can we understand phase behavior of the nonequilibrium problem from an equilibrium approach? J Chem Phys 2016; 144:144902. [DOI: 10.1063/1.4945365] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Affiliation(s)
- Benjamin Trefz
- Institut für Physik, Johannes Gutenberg-Universität, Staudinger Weg 7, 55128 Mainz, Germany
- Graduate School Material Science in Mainz, Staudinger Weg 9, 55128 Mainz, Germany
| | - Subir K. Das
- Theoretical Sciences Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560064, India
| | - Sergei A. Egorov
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, USA
| | - Peter Virnau
- Institut für Physik, Johannes Gutenberg-Universität, Staudinger Weg 7, 55128 Mainz, Germany
| | - Kurt Binder
- Institut für Physik, Johannes Gutenberg-Universität, Staudinger Weg 7, 55128 Mainz, Germany
| |
Collapse
|
8
|
Pütz M, Nielaba P. Effects of temperature on spinodal decomposition and domain growth of liquid-vapor systems with smoothed particle hydrodynamics. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:032303. [PMID: 25871106 DOI: 10.1103/physreve.91.032303] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Indexed: 06/04/2023]
Abstract
We present a numerical method for simulations of spinodal decomposition of liquid-vapor systems. The results are in excellent agreement with theoretical predictions for all expected time regimes from the initial growth of "homophase fluctuations" up to the inertial hydrodynamics regime. The numerical approach follows a modern formulation of the smoothed particle hydrodynamics method with a van der Waals equation of state and thermal conduction. The dynamics and thermal evolution of instantaneously temperature-quenched systems are investigated. Therefore, we introduce a simple scaling thermostat that allows thermal fluctuations at a constant predicted mean temperature. We find that the initial stage spinodal decomposition is strongly affected by the temperature field. The separated phases react on density changes with a change in temperature. Although, the thermal conduction acts very slowly, thermal deviations are eventually compensated. The domain growth in the late stage of demixing is found to be rather unaffected by thermal fluctuations. We observe a transition from the Lifshitz-Slyozov growth rate with 1/3 exponent to the inertial hydrodynamics regime with a rate of 2/3, only excepted from simulations near the critical point where the liquid droplets are observed to nucleate directly in a spherical shape. The transition between the growth regimes is found to occur earlier for higher initial temperatures. We explain this time dependency with the phase interfaces that become more diffuse and overlap with approaching the critical point. A prolonging behavior of the demixing process is observed and also expected to depend on temperature. It is further found that the observations can excellently explain the growth behavior for pure nonisothermal simulations that are performed without thermostat.
Collapse
Affiliation(s)
- Martin Pütz
- Universität Konstanz, Fachbereich für Physik, 78457 Konstanz, Germany
| | - Peter Nielaba
- Universität Konstanz, Fachbereich für Physik, 78457 Konstanz, Germany
| |
Collapse
|
9
|
Das SK. Atomistic simulations of liquid–liquid coexistence in confinement: comparison of thermodynamics and kinetics with bulk. MOLECULAR SIMULATION 2015. [DOI: 10.1080/08927022.2014.998214] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
10
|
Alizadehrad D, Krüger T, Engstler M, Stark H. Simulating the complex cell design of Trypanosoma brucei and its motility. PLoS Comput Biol 2015; 11:e1003967. [PMID: 25569823 PMCID: PMC4288712 DOI: 10.1371/journal.pcbi.1003967] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Accepted: 10/06/2014] [Indexed: 11/19/2022] Open
Abstract
The flagellate Trypanosoma brucei, which causes the sleeping sickness when infecting a mammalian host, goes through an intricate life cycle. It has a rather complex propulsion mechanism and swims in diverse microenvironments. These continuously exert selective pressure, to which the trypanosome adjusts with its architecture and behavior. As a result, the trypanosome assumes a diversity of complex morphotypes during its life cycle. However, although cell biology has detailed form and function of most of them, experimental data on the dynamic behavior and development of most morphotypes is lacking. Here we show that simulation science can predict intermediate cell designs by conducting specific and controlled modifications of an accurate, nature-inspired cell model, which we developed using information from live cell analyses. The cell models account for several important characteristics of the real trypanosomal morphotypes, such as the geometry and elastic properties of the cell body, and their swimming mechanism using an eukaryotic flagellum. We introduce an elastic network model for the cell body, including bending rigidity and simulate swimming in a fluid environment, using the mesoscale simulation technique called multi-particle collision dynamics. The in silico trypanosome of the bloodstream form displays the characteristic in vivo rotational and translational motility pattern that is crucial for survival and virulence in the vertebrate host. Moreover, our model accurately simulates the trypanosome's tumbling and backward motion. We show that the distinctive course of the attached flagellum around the cell body is one important aspect to produce the observed swimming behavior in a viscous fluid, and also required to reach the maximal swimming velocity. Changing details of the flagellar attachment generates less efficient swimmers. We also simulate different morphotypes that occur during the parasite's development in the tsetse fly, and predict a flagellar course we have not been able to measure in experiments so far. Typanosoma brucei is a uni-cellular parasite that causes the sleeping sickness, a deadly disease for humans that also occurs in livestock. Injected into the mammalian host by the tsetse fly, the trypanosome travels through the blood stream, where it proliferates, and ultimately can be taken up again by a fly during a bloodmeal. In the tsetse fly, it continues its development with several morphological changes to the cell body plan. During its life cycle, the trypanosome meets different microenvironments, such as the mammalian's bloodstream and the tsetse fly's midgut, proventriculus, foregut, and salivary gland. The cell body of the trypanosome has the shape of a spindle along which an eukaryotic flagellum is attached. We have developed an accurate, in silico model trypanosome using information from live cell analyses. Performing computer simulations, we are able to reproduce all motility patterns of the blood-stream form in typical cell culture medium. Modifying the cell design, we show that the helical course of the flagellar attachment optimizes the trypanosome's swimming speed. We also design trypanosomal morphotypes that occur in the tsetse fly. Simulation science thereby provides an investigative tool to systematically explore the morphologcial diversity during the trypanosome's life cycle even beyond experimental capabilities.
Collapse
Affiliation(s)
- Davod Alizadehrad
- Institute of Theoretical Physics, Technische Universität Berlin, Berlin, Germany
- * E-mail:
| | - Timothy Krüger
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Markus Engstler
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Holger Stark
- Institute of Theoretical Physics, Technische Universität Berlin, Berlin, Germany
| |
Collapse
|
11
|
Datt C, Thampi SP, Govindarajan R. Morphological evolution of domains in spinodal decomposition. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:010101. [PMID: 25679549 DOI: 10.1103/physreve.91.010101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Indexed: 06/04/2023]
Abstract
Domain growth in spinodal decomposition is usually described by a single time-evolving length scale. We show that the evolution of morphology of domains is nonmonotonic. The domains elongate rapidly at first and then, with the help of hydrodynamics, return to a more circular shape. The initial elongation phase does not alter with hydrodynamics. A small deviation from critical composition changes the morphology dramatically.
Collapse
Affiliation(s)
- Charu Datt
- Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, 21 Brundavan Colony, Narsingi, Hyderabad 500075, India
| | - Sumesh P Thampi
- Rudolf Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford OX1 3NP, United Kingdom
| | - Rama Govindarajan
- Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, 21 Brundavan Colony, Narsingi, Hyderabad 500075, India
| |
Collapse
|
12
|
Multiple patterns of polymer gels in microspheres due to the interplay among phase separation, wetting, and gelation. Proc Natl Acad Sci U S A 2014; 111:15894-9. [PMID: 25349417 DOI: 10.1073/pnas.1416592111] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We report the spontaneous patterning of polymer microgels by confining a polymer blend within microspheres. A poly(ethylene glycol) (PEG) and gelatin solution was confined inside water-in-oil (W/O) microdroplets coated with a layer of zwitterionic lipids: dioleoylphosphatidylethanolamine (PE) and dioleoylphosphatidylcholine (PC). The droplet confinement affected the kinetics of the phase separation, wetting, and gelation after a temperature quench, which determined the final microgel pattern. The gelatin-rich phase completely wetted to the PE membrane and formed a hollow microcapsule as a stable state in the PE droplets. Gelation during phase separation varied the relation between the droplet size and thickness of the capsule wall. In the case of the PC droplets, phase separation was completed only for the smaller droplets, wherein the microgel partially wetted the PC membrane and had a hemisphere shape. In addition, the temperature decrease below the gelation point increased the interfacial tension between the PEG/gelatin phases and triggered a dewetting transition. Interestingly, the accompanying shape deformation to minimize the interfacial area was only observed for the smaller PC droplets. The critical size decreased as the gelatin concentration increased, indicating the role of the gel elasticity as an inhibitor of the deformation. Furthermore, variously patterned microgels with spherically asymmetric shapes, such as discs and stars, were produced as kinetically trapped states by regulating the incubation time, polymer composition, and droplet size. These findings demonstrate a way to regulate the complex shapes of microgels using the interplay among phase separation, wetting, and gelation of confined polymer blends in microdroplets.
Collapse
|
13
|
Binder K, Virnau P, Statt A. Perspective: The Asakura Oosawa model: A colloid prototype for bulk and interfacial phase behavior. J Chem Phys 2014; 141:140901. [DOI: 10.1063/1.4896943] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
|
14
|
Huang A, Bhattacharya A, Binder K. Conformations, transverse fluctuations, and crossover dynamics of a semi-flexible chain in two dimensions. J Chem Phys 2014; 140:214902. [DOI: 10.1063/1.4879537] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
|
15
|
Joksimovic R, Watanabe S, Riemer S, Gradzielski M, Yoshikawa K. Self-organized patterning through the dynamic segregation of DNA and silica nanoparticles. Sci Rep 2014; 4:3660. [PMID: 24413900 PMCID: PMC3888975 DOI: 10.1038/srep03660] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 12/16/2013] [Indexed: 11/28/2022] Open
Abstract
Exotic pattern formation as a result of drying of an aqueous solution containing DNA and silica nanoparticles is reported. The pattern due to segregation was found to critically depend on the relative ratio of nanoparticles and DNA, as revealed by polarization microscopy, scanning electron microscopy, and fluorescence microscopy. The blurred radial pattern that is usually observed in the drying of a colloidal solution was shown to be vividly sharpened in the presence of DNA. Uniquely curved, crescent-shaped micrometer-scale domains are generated in regions that are rich in nanoparticles. The characteristic segregated patterns observed in the present study are interpreted in terms of a large aspect ratio between the persistence length (∼50 nm) and the diameter (∼2 nm) of double-stranded DNA, and the relatively small silica nanoparticles (radius: 5 nm).
Collapse
Affiliation(s)
- Rastko Joksimovic
- 1] Technische Universität Berlin, Institut für Chemie, Strasse des 17. Juni 124, Sekr. TC7, D-10623 Berlin, Germany [2] WPI-AIMR, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
| | - Shun Watanabe
- Faculty of Life and Medical Sciences, Doshisha University, Miyakodani, Kyotanabe, Kyoto 610-0394, Japan
| | - Sven Riemer
- Technische Universität Berlin, Institut für Chemie, Strasse des 17. Juni 124, Sekr. TC7, D-10623 Berlin, Germany
| | - Michael Gradzielski
- Technische Universität Berlin, Institut für Chemie, Strasse des 17. Juni 124, Sekr. TC7, D-10623 Berlin, Germany
| | - Kenichi Yoshikawa
- Faculty of Life and Medical Sciences, Doshisha University, Miyakodani, Kyotanabe, Kyoto 610-0394, Japan
| |
Collapse
|
16
|
Wilms D, Virnau P, Binder K. Stick-slip motion and plastic flow of a two-dimensional colloidal crystal confined to moving corrugated rigid boundaries. Mol Phys 2013. [DOI: 10.1080/00268976.2013.812255] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
17
|
Lichtner K, Klapp SHL. Spinodal decomposition of a binary magnetic fluid confined to a surface. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 88:032301. [PMID: 24125262 DOI: 10.1103/physreve.88.032301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Revised: 08/16/2013] [Indexed: 06/02/2023]
Abstract
In our previous work [J. Chem. Phys. 136, 024502 (2012)], we reported a demixing phase transition of a quasi-two-dimensional, binary Heisenberg fluid mixture driven by the ferromagnetic interactions of the magnetic species. Here, we present a theoretical study for the time-dependent coarsening occurring within the two-phase region in the density-concentration plane, also known as spinodal decomposition. Our investigations are based on dynamical density functional theory (DDFT). The particles in the mixture are modeled as Gaussian soft spheres on a two-dimensional surface, where one component carries a classical spin of Heisenberg type. To investigate the two-phase region, we first present a linear stability analysis with respect to small, harmonic density perturbations. Second, to capture nonlinear effects, we calculate time-dependent structure factors by combining DDFT with Percus' test particle method. For the growth of the average domain size l during spinodal decomposition with time t, we observe a power-law behavior l∝t^{δ_{α}} with δ_{m}≃0.333 for the magnetic species and δ_{n}≃0.323 for the nonmagnetic species.
Collapse
Affiliation(s)
- K Lichtner
- Institute of Theoretical Physics, Secr. EW 7-1, Technical University Berlin, Hardenbergstr. 36, D-10623 Berlin, Germany
| | | |
Collapse
|