1
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Biswas R, Parmar VRS, Thambi AG, Bandyopadhyay R. Correlating microscopic viscoelasticity and structure of an aging colloidal gel using active microrheology and cryogenic scanning electron microscopy. SOFT MATTER 2023; 19:2407-2416. [PMID: 36928531 DOI: 10.1039/d2sm01457b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Optical tweezers (OTs) can detect pico-Newton range forces operating on a colloidal particle trapped in a medium and have been successfully utilized to investigate complex systems with internal structures. LAPONITE® clay particles in an aqueous medium self-assemble to form microscopic networks over time as electrostatic interactions between the particles gradually evolve in a physical aging process. We investigate the forced movements of an optically trapped micron-sized colloidal probe particle, suspended in an aging LAPONITE® suspension, as the underlying LAPONITE® microstructures gradually develop. Our OT-based oscillatory active microrheology experiments allow us to investigate the mechanical responses of the evolving microstructures in aging aqueous clay suspensions of concentrations ranging from 2.5% w/v to 3.0% w/v and at several aging times between 90 and 150 minutes. We repeat such oscillatory measurements for a range of colloidal probe particle diameters and investigate the effect of probe size on the microrheology of the aging suspensions. Using cryogenic field emission scanning electron microscopy (cryo-FESEM), we examine the average pore areas of the LAPONITE® suspension microstructures for various sample concentrations and aging times. By combining our OT and cryo-FESEM data, we report here for the first time to the best of our knowledge, an inverse correlation between the crossover modulus and the average pore diameter of the aging suspension microstructures for the different suspension concentrations and probe particle sizes studied here.
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Affiliation(s)
- Rajkumar Biswas
- Soft Condensed Matter Group, Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560 080, India.
| | - Vaibhav Raj Singh Parmar
- Soft Condensed Matter Group, Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560 080, India.
| | - Anson G Thambi
- Soft Condensed Matter Group, Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560 080, India.
| | - Ranjini Bandyopadhyay
- Soft Condensed Matter Group, Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560 080, India.
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2
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Meng X, Sonn-Segev A, Schumacher A, Cole D, Young G, Thorpe S, Style RW, Dufresne ER, Kukura P. Micromirror Total Internal Reflection Microscopy for High-Performance Single Particle Tracking at Interfaces. ACS PHOTONICS 2021; 8:3111-3118. [PMID: 34692901 PMCID: PMC8532162 DOI: 10.1021/acsphotonics.1c01268] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Indexed: 06/01/2023]
Abstract
Single particle tracking has found broad applications in the life and physical sciences, enabling the observation and characterization of nano- and microscopic motion. Fluorescence-based approaches are ideally suited for high-background environments, such as tracking lipids or proteins in or on cells, due to superior background rejection. Scattering-based detection is preferable when localization precision and imaging speed are paramount due to the in principle infinite photon budget. Here, we show that micromirror-based total internal reflection dark field microscopy enables background suppression previously only reported for interferometric scattering microscopy, resulting in nanometer localization precision at 6 μs exposure time for 20 nm gold nanoparticles with a 25 × 25 μm2 field of view. We demonstrate the capabilities of our implementation by characterizing sub-nanometer deterministic flows of 20 nm gold nanoparticles at liquid-liquid interfaces. Our results approach the optimal combination of background suppression, localization precision, and temporal resolution achievable with pure scattering-based imaging and tracking of nanoparticles at interfaces.
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Affiliation(s)
- Xuanhui Meng
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3TA, U.K.
| | - Adar Sonn-Segev
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3TA, U.K.
| | - Anne Schumacher
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3TA, U.K.
| | - Daniel Cole
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3TA, U.K.
| | - Gavin Young
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3TA, U.K.
| | - Stephen Thorpe
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3TA, U.K.
| | | | | | - Philipp Kukura
- Physical
and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3TA, U.K.
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3
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Abstract
Out of equilibrium, a lack of reciprocity is the rule rather than the exception. Non-reciprocity occurs, for instance, in active matter1-6, non-equilibrium systems7-9, networks of neurons10,11, social groups with conformist and contrarian members12, directional interface growth phenomena13-15 and metamaterials16-20. Although wave propagation in non-reciprocal media has recently been closely studied1,16-20, less is known about the consequences of non-reciprocity on the collective behaviour of many-body systems. Here we show that non-reciprocity leads to time-dependent phases in which spontaneously broken continuous symmetries are dynamically restored. We illustrate this mechanism with simple robotic demonstrations. The resulting phase transitions are controlled by spectral singularities called exceptional points21. We describe the emergence of these phases using insights from bifurcation theory22,23 and non-Hermitian quantum mechanics24,25. Our approach captures non-reciprocal generalizations of three archetypal classes of self-organization out of equilibrium: synchronization, flocking and pattern formation. Collective phenomena in these systems range from active time-(quasi)crystals to exceptional-point-enforced pattern formation and hysteresis. Our work lays the foundation for a general theory of critical phenomena in systems whose dynamics is not governed by an optimization principle.
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4
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Gibson LJ, Zhang S, Stilgoe AB, Nieminen TA, Rubinsztein-Dunlop H. Machine learning wall effects of eccentric spheres for convenient computation. Phys Rev E 2019; 99:043304. [PMID: 31108705 DOI: 10.1103/physreve.99.043304] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Indexed: 06/09/2023]
Abstract
In confined systems, such as the inside of a biological cell, the outer boundary or wall can affect the dynamics of internal particles. In many cases of interest both the internal particle and outer wall are approximately spherical. Therefore, quantifying the wall effects from an outer spherical boundary on the motion of an internal eccentric sphere is very useful. However, when the two spheres are not concentric, the problem becomes nontrivial. In this paper we improve existing analytical methods to evaluate these wall effects and then train a feed-forward artificial neural network within a broader model. The final model generally performed with ∼0.001% error within the training domain and ∼0.05% when the outer spherical wall was extrapolated to an infinite plane. Through this model, the wall effects of an outer spherical boundary on the arbitrary motion of an internal sphere for all experimentally achievable configurations can now be conveniently and efficiently determined.
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Affiliation(s)
- Lachlan J Gibson
- The University of Queensland, School of Mathematics and Physics, Brisbane QLD 4072, Australia
| | - Shu Zhang
- The University of Queensland, School of Mathematics and Physics, Brisbane QLD 4072, Australia
| | - Alexander B Stilgoe
- The University of Queensland, School of Mathematics and Physics, Brisbane QLD 4072, Australia
| | - Timo A Nieminen
- The University of Queensland, School of Mathematics and Physics, Brisbane QLD 4072, Australia
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5
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Debnath T, Li Y, Ghosh PK, Marchesoni F. Active microswimmers in a finite two dimensional trap: The role of hydrodynamic interaction. J Chem Phys 2019; 150:104102. [PMID: 30876348 DOI: 10.1063/1.5038149] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
We investigate the dynamics of two identical artificial active particles suspended in a free-standing fluid film with a trap of finite radius in an acoustic tweezer. In the two dimensional Oseen approximation, their hydrodynamic coupling is long ranged, which naturally raises the question as under what conditions they can simultaneously reside in the trap. We determine a critical value of the hydrodynamic coupling below which that happens and study the ensuing active pair dynamics inside the trap. For larger couplings, only one particle sits in the trap, while the other diffuses freely until it eventually replaces the particle in the trap. Such a mechanism repeats itself with a characteristic noise-dependent mean residence-retrapping time.
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Affiliation(s)
- Tanwi Debnath
- Department of Chemistry, University of Calcutta, Kolkata 700009, India
| | - Yunyun Li
- Center for Phononics and Thermal Energy Science, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
| | - Pulak K Ghosh
- Department of Chemistry, Presidency University, Kolkata 700073, India
| | - Fabio Marchesoni
- Center for Phononics and Thermal Energy Science, School of Physics Science and Engineering, Tongji University, Shanghai 200092, People's Republic of China
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6
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Bae AJ, Hanstorp D, Chang K. Juggling with Light. PHYSICAL REVIEW LETTERS 2019; 122:043902. [PMID: 30768295 DOI: 10.1103/physrevlett.122.043902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Indexed: 06/09/2023]
Abstract
We discovered that when a pair of small particles is optically levitated, the particles execute a "dance" whose motion resembles the orbits of balls being juggled. This motion lies in a plane perpendicular to the polarization of the incident light. We ascribe the dance to a mechanism by which the dominant force on each particle cyclically alternates between radiation pressure and gravity as each particle takes turns eclipsing the other. We explain the plane of motion by considering the anisotropic scattering of polarized light at a curved interface.
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Affiliation(s)
- Albert J Bae
- Max Planck Institute for Dynamics and Self-Organization, 37077 Goettingen, Germany
| | - Dag Hanstorp
- Department of Physics, University of Gothenburg, 412 96 Gothenburg, Sweden
| | - Kelken Chang
- Department of Physics, University of Gothenburg, 412 96 Gothenburg, Sweden
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7
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Li N, Zhang W, Jiang Z, Chen W. Spatial Cross-Correlated Diffusion of Colloids under Shear Flow. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:10537-10542. [PMID: 30117740 DOI: 10.1021/acs.langmuir.8b01803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The spatial cross-correlated diffusion of colloidal particles is often used as an essential tool to study the dynamic properties of a fluid because it directly describes the hydrodynamic interaction between two particles in a fluid. However, the experimental measurement of cross-correlated diffusion can be substantially modified by even a weak shear flow. In this work, the effect of a shear flow on spatial cross-correlated diffusion is demonstrated using experimental measurements that show a clear dependence on pair angles. An analytical solution is proposed to explain the experimental observations. A numerical simulation is performed to systemically demonstrate the influence of shear flow on spatial cross-correlated diffusion. The results of the experiment, theoretical analysis, and numerical simulation agree well with each other. Therefore, this research provides a sensitive experimental method to determine the weak shear flow in any quasi-two-dimensional fluid systems.
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Affiliation(s)
- Na Li
- State Key Laboratory of Surface Physics and Department of Physics , Fudan University , Shanghai 200438 , China
| | - Wei Zhang
- School of Physical Science and Technology , China University of Mining and Technology , Xuzhou 221116 , China
| | - Zehui Jiang
- Department of Physics , Harbin Institute of Technology , Harbin 150001 , China
| | - Wei Chen
- State Key Laboratory of Surface Physics and Department of Physics , Fudan University , Shanghai 200438 , China
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8
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Fernandez-Castanon J, Bianchi S, Saglimbeni F, Di Leonardo R, Sciortino F. Microrheology of DNA hydrogel gelling and melting on cooling. SOFT MATTER 2018; 14:6431-6438. [PMID: 29952388 PMCID: PMC6295875 DOI: 10.1039/c8sm00751a] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 06/16/2018] [Indexed: 05/18/2023]
Abstract
We present systematic characterisation by means of dynamic light scattering and particle tracking techniques of the viscosity and of the linear viscoelastic moduli, G'(ω) and G''(ω), for two different DNA hydrogels. These thermoreversible systems are composed of tetravalent DNA-made nanostars whose sticky sequence is designed to provide controlled interparticle bonding. While the first system forms a gel on cooling, the second one has been programmed to behave as a re-entrant gel, turning again to a fluid solution at low temperature. The frequency-dependent viscous and storage moduli and the viscosity reveal the different viscoelastic behavior of the two DNA hydrogels. Our results show how little variations in the design of the DNA sequences allow tuning of the mechanical response of these biocompatible all-DNA materials.
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Affiliation(s)
| | - Silvio Bianchi
- CNR-NANOTEC, Soft and Living Matter Laboratory, Rome, I-00185, Italy
| | | | - Roberto Di Leonardo
- Dipartimento di Fisica, "Sapienza" Università di Roma, Rome, I-00185, Italy. and CNR-NANOTEC, Soft and Living Matter Laboratory, Rome, I-00185, Italy
| | - Francesco Sciortino
- Dipartimento di Fisica, "Sapienza" Università di Roma, Rome, I-00185, Italy. and CNR-ISC, UOS "Sapienza" Università di Roma, Rome, I-00186, Italy
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9
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Yang W, Misko VR, Marchesoni F, Nori F. Colloidal transport through trap arrays controlled by active microswimmers. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:264004. [PMID: 29775184 DOI: 10.1088/1361-648x/aac61b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We investigate the dynamics of a binary mixture consisting of active and passive colloidal particles diffusing in a 2D array of truncated harmonic wells, or traps. We explore the possibility of using a small fraction of active particles to manipulate a much larger fraction of passive particles, for instance, to confine them in or extract them from the traps. The results of our study have potential application in biology and medical sciences, for example, to remove dead cells or undesired contaminants from biological systems by means of self-propelled nano-robots.
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Affiliation(s)
- Wen Yang
- College of Materials Science and Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, People's Republic of China
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10
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Domínguez A. Theory of anomalous collective diffusion in colloidal monolayers on a spherical interface. Phys Rev E 2018; 97:022607. [PMID: 29548122 DOI: 10.1103/physreve.97.022607] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Indexed: 11/07/2022]
Abstract
A planar colloidal monolayer exhibits anomalous collective diffusion due to the hydrodynamic interactions. We investigate how this behavior is affected by the curvature of the monolayer when it resides on the interface of a spherical droplet. It is found that the characteristic times of the dynamics still exhibit the same anomalous scaling as in the planar case. The spatial distribution, however, shows a difference due to the relevance of the radius of the droplet. Since for the droplet this is both a global magnitude, i.e., pertaining to the spatial extent of the spherical surface, and a local one, i.e., the radius of curvature, the question remains open as to which of these two features actually dominates in the case of a generically curved interface.
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Affiliation(s)
- Alvaro Domínguez
- Física Atómica, Molecular y Nuclear, Universidad de Sevilla, Apdo. 1065, 41080 Sevilla, Spain
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11
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Thorneywork AL, Abbott JL, Aarts DGAL, Keim P, Dullens RPA. Bond-orientational order and Frank's constant in two-dimensional colloidal hard spheres. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:104003. [PMID: 29376830 DOI: 10.1088/1361-648x/aaab31] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Recently, the full phase behaviour of 2D colloidal hard spheres was experimentally established, and found to involve a first order liquid to hexatic transition and a continuous hexatic to crystal transition (Thorneywork et al 2017 Phys. Rev. Lett. 118 158001). Here, we expand upon this work by considering the behaviour of the bond-orientational correlation time and Frank's constant in the region of these phase transitions. We also consider the excess entropy, as calculated from the radial distribution functions, for a wide range of area fractions covering the liquid, hexatic and crystal phases. In all cases, the behaviour of these quantities further corroborates the previously reported melting scenario of 2D colloidal hard spheres.
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Affiliation(s)
- Alice L Thorneywork
- Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, United Kingdom. Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, United Kingdom
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12
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Sarfati R, Dufresne ER. Long-range attraction of particles adhered to lipid vesicles. Phys Rev E 2016; 94:012604. [PMID: 27575176 DOI: 10.1103/physreve.94.012604] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Indexed: 01/18/2023]
Abstract
Many biological systems fold thin sheets of lipid membrane into complex three-dimensional structures. This microscopic origami is often mediated by the adsorption and self-assembly of proteins on a membrane. As a model system to study adsorption-mediated interactions, we study the collective behavior of micrometric particles adhered to a lipid vesicle. We estimate the colloidal interactions using a maximum likelihood analysis of particle trajectories. When the particles are highly wrapped by a tense membrane, we observe strong long-range attractions with a typical binding energy of 150k_{B}T and significant forces extending a few microns.
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Affiliation(s)
- Raphael Sarfati
- Department of Applied Physics and Integrated Graduate Program in Physical and Engineering Biology, Yale University, New Haven, Connecticut 06511, USA
| | - Eric R Dufresne
- Department of Materials ETH Zürich, 8092 Zürich, Switzerland and School of Engineering and Applied Sciences, Yale University, New Haven, Connecticut 06511, USA
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13
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Hydrodynamic collective effects of active protein machines in solution and lipid bilayers. Proc Natl Acad Sci U S A 2015; 112:E3639-44. [PMID: 26124140 DOI: 10.1073/pnas.1506825112] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The cytoplasm and biomembranes in biological cells contain large numbers of proteins that cyclically change their shapes. They are molecular machines that can function as molecular motors or carry out various other tasks in the cell. Many enzymes also undergo conformational changes within their turnover cycles. We analyze the advection effects that nonthermal fluctuating hydrodynamic flows induced by active proteins have on other passive molecules in solution or membranes. We show that the diffusion constants of passive particles are enhanced substantially. Furthermore, when gradients of active proteins are present, a chemotaxis-like drift of passive particles takes place. In lipid bilayers, the effects are strongly nonlocal, so that active inclusions in the entire membrane contribute to local diffusion enhancement and the drift. All active proteins in a biological cell or in a membrane contribute to such effects and all passive particles, and the proteins themselves, will be subject to them.
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14
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Measuring and overcoming limits of the Saffman-Delbrück model for soap film viscosities. PLoS One 2015; 10:e0121981. [PMID: 25822262 PMCID: PMC4379181 DOI: 10.1371/journal.pone.0121981] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 02/06/2015] [Indexed: 01/29/2023] Open
Abstract
We observe tracer particles diffusing in soap films to measure the two-dimensional (2D) viscous properties of the films. Saffman-Delbrück type models relate the single-particle diffusivity to parameters of the film (such as thickness h) for thin films, but the relation breaks down for thicker films. Notably, the diffusivity is faster than expected for thicker films, with the crossover at h/d = 5.2 ± 0.9 using the tracer particle diameter d. This indicates a crossover from purely 2D diffusion to diffusion that is more three-dimensional. We demonstrate that measuring the correlations of particle pairs as a function of their separation overcomes the limitations of the Saffman-Delbrück model and allows one to measure the viscosity of a soap film for any thickness.
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15
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Domínguez A. Signature of time-dependent hydrodynamic interactions on collective diffusion in colloidal monolayers. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2014; 90:062314. [PMID: 25615100 DOI: 10.1103/physreve.90.062314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Indexed: 06/04/2023]
Abstract
It has been shown recently that the coefficient of collective diffusion in a colloidal monolayer is divergent due to the hydrodynamic interactions mediated by the ambient fluid in bulk. The analysis is extended to allow for time-dependent hydrodynamic interactions. Observational features specific to this time dependency are predicted. The possible experimental detection in the dynamics of the monolayer is discussed.
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Affiliation(s)
- Alvaro Domínguez
- Física Teórica, Universidad de Sevilla, Apdo. 1065, 41080 Sevilla, Spain
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16
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Giomi L, Bowick MJ, Mishra P, Sknepnek R, Cristina Marchetti M. Defect dynamics in active nematics. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2014; 372:20130365. [PMID: 25332389 PMCID: PMC4223672 DOI: 10.1098/rsta.2013.0365] [Citation(s) in RCA: 111] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Topological defects are distinctive signatures of liquid crystals. They profoundly affect the viscoelastic behaviour of the fluid by constraining the orientational structure in a way that inevitably requires global changes not achievable with any set of local deformations. In active nematic liquid crystals, topological defects not only dictate the global structure of the director, but also act as local sources of motion, behaving as self-propelled particles. In this article, we present a detailed analytical and numerical study of the mechanics of topological defects in active nematic liquid crystals.
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Affiliation(s)
- Luca Giomi
- SISSA, International School for Advanced Studies, Via Bonomea 265, 34136 Trieste, Italy Instituut-Lorentz, Universiteit Leiden, PO Box 9506, 2300 RA Leiden, The Netherlands
| | - Mark J Bowick
- Physics Department and Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
| | - Prashant Mishra
- Physics Department, Syracuse University, Syracuse, NY 13244, USA
| | - Rastko Sknepnek
- School of Engineering, Physics, and Mathematics, University of Dundee, Dundee DD1 4HN, UK
| | - M Cristina Marchetti
- Physics Department and Syracuse Biomaterials Institute, Syracuse University, Syracuse, NY 13244, USA
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17
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Qi Z, Nguyen ZH, Park CS, Glaser MA, Maclennan JE, Clark NA, Kuriabova T, Powers TR. Mutual diffusion of inclusions in freely suspended smectic liquid crystal films. PHYSICAL REVIEW LETTERS 2014; 113:128304. [PMID: 25279649 DOI: 10.1103/physrevlett.113.128304] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Indexed: 06/03/2023]
Abstract
We study experimentally and theoretically the hydrodynamic interaction of pairs of circular inclusions in two-dimensional, fluid smectic membranes suspended in air. By analyzing their Brownian motion, we find that the radial mutual mobilities of identical inclusions are independent of their size but that the angular coupling becomes strongly size dependent when their radius exceeds a characteristic hydrodynamic length. These observations are described well for arbitrary inclusion separations by a model that generalizes the Levine-MacKintosh theory of point-force response functions and uses a boundary-element approach to calculate the mobility matrix for inclusions of finite extent.
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Affiliation(s)
- Zhiyuan Qi
- Department of Physics and the Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA
| | - Zoom Hoang Nguyen
- Department of Physics and the Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA
| | - Cheol Soo Park
- Department of Physics and the Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA
| | - Matthew A Glaser
- Department of Physics and the Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA
| | - Joseph E Maclennan
- Department of Physics and the Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA
| | - Noel A Clark
- Department of Physics and the Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, USA
| | - Tatiana Kuriabova
- School of Engineering, Brown University, Providence, Rhode Island 02912, USA
| | - Thomas R Powers
- School of Engineering, Brown University, Providence, Rhode Island 02912, USA and Department of Physics, Brown University, Providence, Rhode Island 02912, USA
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18
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Sung BJ, Yethiraj A. Dynamics of two-dimensional and quasi-two-dimensional polymers. J Chem Phys 2013; 138:234904. [DOI: 10.1063/1.4810755] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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19
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Malgaretti P, Pagonabarraga I, Frenkel D. Running faster together: huge speed up of thermal ratchets due to hydrodynamic coupling. PHYSICAL REVIEW LETTERS 2012; 109:168101. [PMID: 23215133 DOI: 10.1103/physrevlett.109.168101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2011] [Revised: 09/05/2012] [Indexed: 06/01/2023]
Abstract
We present simulations that reveal a surprisingly large effect of hydrodynamic coupling on the speed of thermal ratchet motors. The model that we use considers particles performing thermal ratchet motion in a hydrodynamic solvent. Using particle-based, mesoscopic simulations that maintain local momentum conservation, we analyze quantitatively how the coupling to the surrounding fluid affects ratchet motion. We find that coupling can increase the mean velocity of the moving particles by almost 2 orders of magnitude, precisely because ratchet motion has both a diffusive and a deterministic component. The resulting coupling also leads to the formation of aggregates at longer times. The correlated motion that we describe increases the efficiency of motor-delivered cargo transport and we speculate that the mechanism that we have uncovered may play a key role in speeding up molecular motor-driven intracellular transport.
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Affiliation(s)
- Paolo Malgaretti
- Department de Fisica Fonamental, Universitat de Barcelona, Carrer Marti i Franques 1, 08028 Barcelona, Spain.
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20
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Ruh D, Tränkle B, Rohrbach A. Fast parallel interferometric 3D tracking of numerous optically trapped particles and their hydrodynamic interaction. OPTICS EXPRESS 2011; 19:21627-21642. [PMID: 22109012 DOI: 10.1364/oe.19.021627] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Multi-dimensional, correlated particle tracking is a key technology to reveal dynamic processes in living and synthetic soft matter systems. In this paper we present a new method for tracking micron-sized beads in parallel and in all three dimensions - faster and more precise than existing techniques. Using an acousto-optic deflector and two quadrant-photo-diodes, we can track numerous optically trapped beads at up to tens of kHz with a precision of a few nanometers by back-focal plane interferometry. By time-multiplexing the laser focus, we can calibrate individually all traps and all tracking signals in a few seconds and in 3D. We show 3D histograms and calibration constants for nine beads in a quadratic arrangement, although trapping and tracking is easily possible for more beads also in arbitrary 2D arrangements. As an application, we investigate the hydrodynamic coupling and diffusion anomalies of spheres trapped in a 3 × 3 arrangement.
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Affiliation(s)
- Dominic Ruh
- Laboratory for Bio- and Nano- Photonics, Department of Microsystems Engineering-IMTEK, University of Freiburg, Georges Köhler Allee 102, 79110 Freiburg, Germany
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Di Leonardo R, Cammarota E, Bolognesi G, Schäfer H, Steinhart M. Three-dimensional to two-dimensional crossover in the hydrodynamic interactions between micron-scale rods. PHYSICAL REVIEW LETTERS 2011; 107:044501. [PMID: 21867010 DOI: 10.1103/physrevlett.107.044501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Indexed: 05/31/2023]
Abstract
Moving micron-scale objects are strongly coupled to each other by hydrodynamic interactions. The strength of this coupling decays with the inverse particle separation when the two objects are sufficiently far apart. It has been recently demonstrated that the reduced dimensionality of a thin fluid layer gives rise to longer-ranged, logarithmic coupling. Using holographic tweezers we show that microrods display both behaviors interacting like point particles in three dimensions at large distances and like point particles in two dimensions for distances shorter then their length. We derive a simple analytical expression that fits our data remarkably well and further validate it with finite element analysis.
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Affiliation(s)
- R Di Leonardo
- IPCF-CNR, UOS Roma, Piazzale Aldo Moro 2, I-00185, Roma, Italy
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Padgett M, Di Leonardo R. Holographic optical tweezers and their relevance to lab on chip devices. LAB ON A CHIP 2011; 11:1196-205. [PMID: 21327211 DOI: 10.1039/c0lc00526f] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
During the last decade, optical tweezers have been transformed by the combined availability of spatial light modulators and the speed of low-cost computing to drive them. Holographic optical tweezers can trap and move many objects simultaneously and their compatibility with other optical techniques, particularly microscopy, means that they are highly appropriate to lab-on-chip systems to enable optical manipulation, actuation and sensing.
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Affiliation(s)
- Miles Padgett
- School of Physics and Astronomy, SUPA, University of Glasgow, Scotland.
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Curran A, Yao AM, Gibson GM, Bowman R, Cooper JM, Padgett ML. Real time characterization of hydrodynamics in optically trapped networks of micro-particles. JOURNAL OF BIOPHOTONICS 2010; 3:244-251. [PMID: 20301124 DOI: 10.1002/jbio.201000003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The hydrodynamic interactions of micro-silica spheres trapped in a variety of networks using holographic optical tweezers are measured and characterized in terms of their predicted eigenmodes. The characteristic eigenmodes of the networks are distinguishable within 20-40 seconds of acquisition time. Three different multi-particle networks are considered; an eight-particle linear chain, a nine-particle square grid and, finally, an eight-particle ring. The eigenmodes and their decay rates are shown to behave as predicted by the Oseen tensor and the Langevin equation, respectively. Finally, we demonstrate the potential of using our micro-ring as a non-invasive sensor to the local environmental viscosity, by showing the distortion of the eigenmode spectrum due to the proximity of a planar boundary.
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Affiliation(s)
- Arran Curran
- Department of Physics and Astronomy, University of Glasgow, Glasgow, UK.
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Prasad V, Weeks ER. Flow fields in soap films: Relating viscosity and film thickness. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 80:026309. [PMID: 19792251 DOI: 10.1103/physreve.80.026309] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2009] [Indexed: 05/28/2023]
Abstract
We follow the diffusive motion of colloidal particles in soap films with varying h / d, where h is the thickness of the film and d is the diameter of the particles. The hydrodynamics of these films are determined by looking at the correlated motion of pairs of particles as a function of separation R. The Trapeznikov approximation [A. A. Trapeznikov, (Butterworths, London, 1957), p. 242] is used to model soap films as an effective two-dimensional (2D) fluid in contact with bulk air phases. The flow fields determined from correlated particle motions show excellent agreement with what is expected for the theory of 2D fluids for all our films where 0.6 < or = h / d < or = 14.3 , with the 2D shear viscosity matching that predicted by Trapeznikov. However, the parameters of these flow fields change markedly for thick films (h / d > 7 + or - 3) . Our results indicate that three-dimensional effects become important for these thicker films, despite the flow fields still having a 2D character.
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Affiliation(s)
- V Prasad
- Department of Physics, Emory University, Atlanta, Georgia 30322, USA
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Sané J, Padding JT, Louis AA. Hydrodynamics of confined colloidal fluids in two dimensions. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:051402. [PMID: 19518451 DOI: 10.1103/physreve.79.051402] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2008] [Indexed: 05/15/2023]
Abstract
We apply a hybrid molecular dynamics and mesoscopic simulation technique to study the dynamics of two-dimensional colloidal disks in confined geometries. We calculate the velocity autocorrelation functions and observe the predicted t;{-1} long-time hydrodynamic tail that characterizes unconfined fluids, as well as more complex oscillating behavior and negative tails for strongly confined geometries. Because the t;{-1} tail of the velocity autocorrelation function is cut off for longer times in finite systems, the related diffusion coefficient does not diverge but instead depends logarithmically on the overall size of the system. The Langevin equation gives a poor approximation to the velocity autocorrelation function at both short and long times.
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Affiliation(s)
- Jimaan Sané
- Rudolf Peierls Centre for Theoretical Physics, 1 Keble Road, Oxford OX1 3NP, United Kingdom
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Cernák J, Helgesen G. Aggregation of magnetic holes in a rotating magnetic field. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2008; 78:061401. [PMID: 19256835 DOI: 10.1103/physreve.78.061401] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2008] [Indexed: 05/27/2023]
Abstract
We experimentally investigated field-induced aggregation of nonmagnetic particles confined in a magnetic fluid layer when rotating magnetic fields were applied. After application of a magnetic field rotating in the plane of the fluid layer, the single particles start to form two-dimensional clusters, like dimers, trimers, and more complex structures. These clusters aggregated again and again to form bigger clusters. During this nonequilibrium process, a broad range of cluster sizes was formed, and the scaling exponents z and z;{'} of the number of clusters N(t) approximately t;{-z;{'}} and average cluster size S(t) approximately t;{z} were calculated. The process could be characterized as diffusion-limited cluster-cluster aggregation. We found that all sizes of clusters that occurred during an experiment fall on a single curve, as the dynamic scaling theory predicts. However, the characteristic scaling exponents z;{'},z and crossover exponents Delta were not universal. A particle tracking method was used to find the dependence of the diffusion coefficients D_{s} on cluster size s . The cluster motions show features of Brownian motion. The average diffusion coefficients D_{s} depend on the cluster size s as a power law D_{s} proportional, variants;{gamma} where values of gamma as different as gamma=-0.62+/-0.19 and gamma=-2.08+/-0.51 were found in two of the experiments.
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Affiliation(s)
- Jozef Cernák
- Institute of Physics, P. J. Safárik University in Kosice, Jesenná 5, SK-04000 Kosice, Slovak Republic.
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