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Leoni F, Calero C, Franzese G. Nanoconfined Fluids: Uniqueness of Water Compared to Other Liquids. ACS NANO 2021; 15:19864-19876. [PMID: 34807577 PMCID: PMC8717635 DOI: 10.1021/acsnano.1c07381] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/18/2021] [Indexed: 05/27/2023]
Abstract
Nanoconfinement can drastically change the behavior of liquids, puzzling us with counterintuitive properties. It is relevant in applications, including decontamination and crystallization control. However, it still lacks a systematic analysis for fluids with different bulk properties. Here we address this gap. We compare, by molecular dynamics simulations, three different liquids in a graphene slit pore: (1) A simple fluid, such as argon, described by a Lennard-Jones potential; (2) an anomalous fluid, such as a liquid metal, modeled with an isotropic core-softened potential; and (3) water, the prototypical anomalous liquid, with directional HBs. We study how the slit-pore width affects the structure, thermodynamics, and dynamics of the fluids. All the fluids show similar oscillating properties by changing the pore size. However, their free-energy minima are quite different in nature: (i) are energy-driven for the simple liquid; (ii) are entropy-driven for the isotropic core-softened potential; and (iii) have a changing nature for water. Indeed, for water, the monolayer minimum is entropy driven, at variance with the simple liquid, while the bilayer minimum is energy driven, at variance with the other anomalous liquid. Also, water has a large increase in diffusion for subnm slit pores, becoming faster than bulk. Instead, the other two fluids have diffusion oscillations much smaller than water, slowing down for decreasing slit-pore width. Our results, clarifying that water confined at the subnm scale behaves differently from other (simple or anomalous) fluids under similar confinement, are possibly relevant in nanopores applications, for example, in water purification from contaminants.
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Affiliation(s)
- Fabio Leoni
- Department
of Physics, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy
| | - Carles Calero
- Secció
de Física Estadística i Interdisciplinària-Departament
de Física de la Matèria Condensada, Institut de Nanociència i Nanotecnologia (IN2UB), Universitat
de Barcelona, Carrer Martí i Franquès 1, 08028 Barcelona, Spain
| | - Giancarlo Franzese
- Secció
de Física Estadística i Interdisciplinària-Departament
de Física de la Matèria Condensada, Institut de Nanociència i Nanotecnologia (IN2UB), Universitat
de Barcelona, Carrer Martí i Franquès 1, 08028 Barcelona, Spain
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Thermodynamics of interfaces extended to nanoscales by introducing integral and differential surface tensions. Proc Natl Acad Sci U S A 2021; 118:2019873118. [PMID: 33452136 DOI: 10.1073/pnas.2019873118] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
As a system shrinks down in size, more and more molecules are found in its surface region, so surface contribution becomes a large or even a dominant part of its thermodynamic potentials. Surface tension is a venerable scientific concept; Gibbs defined it as the excess of grand potential of an inhomogeneous system with respect to its bulk value per interface area [J. W. Gibbs, "The Collected Works" in Thermodynamics (1928), Vol. 1]. The mechanical definition expresses it in terms of pressure tensor. So far, it has been believed the two definitions always give the same result. We show that the equivalence can break down for fluids confined in narrow pores. New concepts of integral and differential surface tensions, along with integral and differential adsorptions, need to be introduced for extending Gibbs thermodynamics of interfaces. We derived two generalized Gibbs adsorption equations. These concepts are indispensable for an adequate description of nanoscale systems. We also find a relation between integral surface tension and Derjaguin's disjoining pressure. This lays down the basis for measuring integral and differential surface tensions from disjoining pressure by using an atomic force microscope.
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Nanjundiah K, Kurian A, Kaur S, Singla S, Dhinojwala A. Crystallinelike Ordering of Confined Liquids at the Moving Contact Line. PHYSICAL REVIEW LETTERS 2019; 122:128004. [PMID: 30978075 DOI: 10.1103/physrevlett.122.128004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Indexed: 06/09/2023]
Abstract
The friction between a liquid swollen soft elastomer and a solid surface depends on the state of a confined liquid. To measure the physical state of the confined liquid, an interface-sensitive sum frequency generation spectroscopy technique was used to probe the contact region. We find that during sliding (friction) and pull-off (adhesion) experiments of pentadecane-swollen poly(dimethyl siloxane) lenses submerged in linear alkane (pentadecane) on a sapphire substrate, crystallinelike ordering of the liquid occurs only at the contact line, where we anticipate the highest shear. This crystallinelike structure of pentadecane molecules is transient and shows Arrhenius temperature dependence with unusually long relaxation times (hundreds of seconds) and an activation energy (50 kJ/mole), which is twice that of the bulk pentadecane liquid, at temperatures that are 14-70 °C higher than the bulk melting temperature (T_{m}=9 °C). This unusual long-lived crystallinelike ordering may explain why these systems show higher friction coefficients (boundary lubrication) compared to values predicted using bulk viscosity of pentadecane (hydrodynamic lubrication).
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Karzar Jeddi M, Romero-Vargas Castrillón S. Dynamics of Water Monolayers Confined by Chemically Heterogeneous Surfaces: Observation of Surface-Induced Anisotropic Diffusion. J Phys Chem B 2017; 121:9666-9675. [PMID: 28938070 DOI: 10.1021/acs.jpcb.7b07454] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Water present in confining geometries plays key roles in many systems of scientific and technological relevance. Prominent examples are living cells and nanofluidic devices. Despite its importance, a complete understanding of the dynamics of water in nanoscale confinement remains elusive. In this work, we use molecular dynamics (MD) simulation to investigate the diffusive dynamics of water monolayers confined in chemically heterogeneous silica slit pores. The effect of chemical heterogeneity is systematically investigated through the fraction fSiOH of randomly distributed surface sites that possess hydroxyl functional groups. Partial hydroxylation results in heterogeneous surfaces comprising nanoscale hydrophobic and hydrophilic regions. We find that the in-plane diffusivity of water increases monotonically with fSiOH; at low surface hydroxylation (fSiOH ≤ 50%), slow water dynamics arise due to the formation of icelike structures in the hydrophobic regions, while at fSiOH ≥ 75%, surface-water H-bonds in the hydrophilic regions result in faster dynamics. We show that surface patterning with ordered hydrophobic and hydrophilic "stripes" can be used to induce one-dimensional diffusion, with water diffusing through the slit pore preferentially along the direction of the hydrophilic surface patterns.
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Affiliation(s)
- Mehdi Karzar Jeddi
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota-Twin Cities , Minneapolis, Minnesota 55455, United States
| | - Santiago Romero-Vargas Castrillón
- Department of Civil, Environmental, and Geo- Engineering, University of Minnesota-Twin Cities , Minneapolis, Minnesota 55455, United States
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5
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Multiscale simulation on shearing transitions of thin-film lubrication with multi-layer molecules. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.04.079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Abstract
Intermittent sliding (stick-slip motion) between solids is commonplace (e.g., squeaking hinges), even in the presence of lubricants, and is believed to occur by shear-induced fluidization of the lubricant film (slip), followed by its resolidification (stick). Using a surface force balance, we measure how the thickness of molecularly thin, model lubricant films (octamethylcyclotetrasiloxane) varies in stick-slip sliding between atomically smooth surfaces during the fleeting (ca. 20 ms) individual slip events. Shear fluidization of a film of five to six molecular layers during an individual slip event should result in film dilation of 0.4-0.5 nm, but our results show that, within our resolution of ca. 0.1 nm, slip of the surfaces is not correlated with any dilation of the intersurface gap. This reveals that, unlike what is commonly supposed, slip does not occur by such shear melting, and indicates that other mechanisms, such as intralayer slip within the lubricant film, or at its interface with the confining surfaces, may be the dominant dissipation modes.
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Numaguchi R, Tanaka H, Watanabe S, Miyahara MT. Simulation study for adsorption-induced structural transition in stacked-layer porous coordination polymers: Equilibrium and hysteretic adsorption behaviors. J Chem Phys 2013; 138:054708. [DOI: 10.1063/1.4789810] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Kalyanasundaram V, Spearot DE, Malshe AP. Molecular dynamics simulation of nanoconfinement induced organization of n-decane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:7553-7560. [PMID: 19507848 DOI: 10.1021/la901285f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Molecular dynamics (MD) simulations are used to study the behavior of n-decane under sub-10 nm confinement between two gold {111} surfaces. This confinement and dielectric medium are characteristic of those used in nanoscale electromachining (nano-EM) processes; thus, it is important that the behavior of the nanoconfined dielectric medium be investigated for better process understanding. Results obtained via MD simulations indicate that, when confined down to a thickness less than 1 nm, the mechanical boundary conditions trigger organization in the n-decane medium, resulting in two distinct molecular layers. The n-decane chains lie flat on the {111} gold surfaces and show preferred orientation in the close-packed 110 crystallographic directions. A 4-fold increase in the maximum local density as compared with the experimental bulk (liquid) density is observed at the interface between the molecular medium and the gold {111} surfaces, regardless of confinement spacing. Radial distribution function curves are used to quantitatively examine organization of the medium into molecular layers. The deliberate introduction of ledges (atomic steps) on the gold surface triggers a preferred alignment of the n-decane chains toward the boundaries of the ledges.
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Grabowski CA, Mukhopadhyay A. Comparing the activation energy of diffusion in bulk and ultrathin fluid films. J Chem Phys 2007; 127:171101. [PMID: 17994799 DOI: 10.1063/1.2802198] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have measured the activation energy (E act) of translational diffusion for a dissolved fluorescent dye in bulk and within an ultrathin liquid film formed on a solid substrate. The experiments were performed using the single-molecule sensitive technique of fluorescence correlation spectroscopy. From the temperature-dependent measurements, we have determined that the activation energy for a few nanometer thick fluid film increases by a factor of approximately 3-4 compared to bulk liquid. The results are confirmed for two distinctly different systems in regard to molecular shape, tetrakis (2-ethylhexoxy) silane and hexadecane.
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11
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Schoen M. Fluid bridges confined between chemically nanopatterned solid substrates. Phys Chem Chem Phys 2007; 10:223-56. [PMID: 18213411 DOI: 10.1039/b706674k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We discuss equilibrium properties of classical fluids confined to nanoscopic volumes by solid substrates. The substrates themselves are endowed with wettable chemical patterns of variable symmetry. We develop a thermodynamic description suitable for these highly anisotropic systems. Based upon a combination of Monte Carlo simulations in the grand canonical ensemble and lattice density functional theory at mean-field level we analyze the structure and phase behaviour of the confined fluid. Under suitable thermodynamic conditions the fluid may condense partially in regions controlled by the wettable nanopatterns. The resulting fluid bridges are established as thermodynamic phases and exhibit unique rheological features.
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Affiliation(s)
- Martin Schoen
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Fakultät für Mathematik und Naturwissenschaften, Technische Universität Berlin, Strasse des 17. Juni 135, Berlin, Germany.
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12
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Klein J. Frictional dissipation in stick-slip sliding. PHYSICAL REVIEW LETTERS 2007; 98:056101. [PMID: 17358875 DOI: 10.1103/physrevlett.98.056101] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Indexed: 05/14/2023]
Abstract
The time variation of the frictional force between two surfaces, undergoing stick-slip sliding across a molecularly thin film of a confined model liquid, was examined at high time and force resolution, showing clearly that dissipation of energy occurs both during the slip, and at the instant of stick (via transfer of residual momentum). Detailed analysis indicates that, in marked contrast to earlier suggestions, of order 90% or more of the dissipation occurs by viscous heating of the confined shear-melted film during the slip, and only a small fraction of the energy is dissipated at the instant of stick.
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Affiliation(s)
- Jacob Klein
- Physical and Theoretical Chemistry, Oxford University, Oxford OX1 3QZ, United Kingdom
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Zheng JM, Chin WC, Khijniak E, Khijniak E, Pollack GH. Surfaces and interfacial water: evidence that hydrophilic surfaces have long-range impact. Adv Colloid Interface Sci 2006; 127:19-27. [PMID: 16952332 DOI: 10.1016/j.cis.2006.07.002] [Citation(s) in RCA: 183] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Accepted: 07/18/2006] [Indexed: 11/29/2022]
Abstract
It is generally thought that the impact of surfaces on the contiguous aqueous phase extends to a distance of no more than a few water-molecule layers. Older studies, on the other hand, suggest a more extensive impact. We report here that colloidal and molecular solutes suspended in aqueous solution are profoundly and extensively excluded from the vicinity of various hydrophilic surfaces. The width of the solute-free zone is typically several hundred microns. Such large exclusion zones were observed in the vicinity of many types of surface including artificial and natural hydrogels, biological tissues, hydrophilic polymers, monolayers, and ion-exchange beads, as well as with a variety of solutes. Using microscopic observations, as well as measurements of electrical potential and UV-Vis absorption-spectra, infrared imaging, and NMR imaging, we find that the solute-free zone is a physically distinct and less mobile phase of water that can co-exist indefinitely with the contiguous solute-containing phase. The extensiveness of this modified zone is impressive, and carries broad implication for surface-molecule interactions in many realms, including cellular recognition, biomaterial-surface antifouling, bioseparation technologies, and other areas of biology, physics and chemistry.
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Affiliation(s)
- Jian-Ming Zheng
- Department of Bioengineering, Box 355061, University of Washington, Seattle, WA 98195, USA
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Hemming CJ, Patey GN. Nanoscopic Liquid Bridges between Chemically Patterned Atomistic Walls. J Phys Chem B 2006; 110:3764-72. [PMID: 16494435 DOI: 10.1021/jp056331l] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A binary liquid mixture, containing the Lennard-Jones molecules A and B, in equilibrium with a bulk liquid reservoir near the point of phase separation, confined between atomistic chemically patterned walls, is studied by grand canonical Monte Carlo simulations. In the bulk, the B-rich phase is stable and the A-rich phase is metastable. The walls bear patches attractive to A; when the walls are close, A-rich liquid bridges condense between the patches. The normal and lateral forces on the walls are measured as a function of the wall separation and of the lateral displacement between the patches on opposite walls. When there are one or two molecular layers in the bridge and the wall lattice constant is close to that of crystalline A, the normal and lateral forces depend strongly on the registry of the wall lattices, varying in an oscillatory manner.
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Affiliation(s)
- C J Hemming
- Department of Chemistry, University of British Columbia, Vancouver, British Columbia V6T 1Z1, Canada
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Granick S, Kumar SK, Amis EJ, Antonietti M, Balazs AC, Chakraborty AK, Grest GS, Hawker C, Janmey P, Kramer EJ, Nuzzo R, Russell TP, Safinya CR. Macromolecules at surfaces: Research challenges and opportunities from tribology to biology. ACTA ACUST UNITED AC 2003. [DOI: 10.1002/polb.10669] [Citation(s) in RCA: 144] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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16
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Cámara LG, Bresme F. Molecular dynamics simulations of crystallization under confinement at triple point conditions. J Chem Phys 2003. [DOI: 10.1063/1.1587127] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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17
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Mukhopadhyay A, Zhao J, Bae SC, Granick S. Contrasting friction and diffusion in molecularly thin confined films. PHYSICAL REVIEW LETTERS 2002; 89:136103. [PMID: 12225043 DOI: 10.1103/physrevlett.89.136103] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2002] [Indexed: 05/23/2023]
Abstract
We study, using fluorescence correlation spectroscopy, translational diffusion in molecularly thin liquids confined within a surface forces apparatus. The diffusion coefficient decreases exponentially from the edges towards the center of the Hertzian contact and further suggests the presence of a small number of distinct diffusion processes. This holds alike a crystallizable fluid (OMCTS) and a glass-former (1,2-propane diol), both of which displayed static friction. We conclude that friction, the average of an ensemble of molecules, masked massively heterogeneous molecular mobility.
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Affiliation(s)
- Ashis Mukhopadhyay
- Department of Materials Science and Engineering, University of Illinois, Urbana, Illinois 61801, USA
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18
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Influence of molecular structure on the properties of confined fluids by molecular dynamics simulation. Colloids Surf A Physicochem Eng Asp 2002. [DOI: 10.1016/s0927-7757(02)00085-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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19
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Paserba KR, Gellman AJ. Effects of conformational isomerism on the desorption kinetics of n-alkanes from graphite. J Chem Phys 2001. [DOI: 10.1063/1.1398574] [Citation(s) in RCA: 118] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
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20
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Gao GT, Zeng XC, Diestler DJ. Nonlinear effects of physisorption on static friction. J Chem Phys 2000. [DOI: 10.1063/1.1326416] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Wang JC, Fichthorn KA. A method for molecular dynamics simulation of confined fluids. J Chem Phys 2000. [DOI: 10.1063/1.481430] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Blyakhman FA, Shklyar T, Pollack GH. Quantal length changes in single contracting sarcomeres. J Muscle Res Cell Motil 1999; 20:529-38. [PMID: 10555071 DOI: 10.1023/a:1005590401721] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The time course of shortening was investigated in the single sarcomere, the smallest contractile unit that retains natural structure. We projected the striation patterns of single bumblebee flight-muscle myofibrils onto a linear photodiode array, which was scanned periodically to produce repetitive traces of intensity vs. position along the array. Sarcomere length was taken as the span between adjacent A-band or Z-line centroids. When myofibrils were ramp-released by a motor, individual sarcomeres shortened in steps punctuated by pauses. The single sarcomere-shortening trace was consistently stepwise both in activated and relaxed specimens. Although step size was variable, the size distribution showed a signature-like feature: the histogram comprised distinct peaks that were spaced quasi-regularly. In the activated myofibrils the interpeak separation corresponded to 2.71 nm per half-sarcomere. This value is equal to the linear advance of actin subunits along the thin filament. Thus, actin filaments translate over thick filaments by steps that may be integer multiples of the actin-subunit spacing.
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Affiliation(s)
- F A Blyakhman
- Department of Bioengineering, University of Washington, Seattle 98195, USA
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24
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Cui ST, Cummings PT, Cochran HD. Molecular dynamics simulation of the rheological and dynamical properties of a model alkane fluid under confinement. J Chem Phys 1999. [DOI: 10.1063/1.479312] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Pollack GH, Blyakhman F, Shklyar T, Tourovskaya A, Tameyasu T, Yang P. Implications of quantal motor action in biological systems. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1999; 453:361-9; discussion 370-1. [PMID: 9889848 DOI: 10.1007/978-1-4684-6039-1_41] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
We demonstrate in this paper that quantal behavior is a central feature of biological motile and contractile systems. Step-like behavior has been demonstrated in the interaction between single molecules and filaments both in the kinesin-microtubule system and in the myosin-actin filament system. We show here that the step-like molecular features appear also in the single intact sarcomere. We studied single sarcomeres of single bumble-bee myofibrils, both in the unactivated and activated states. Myofibril-length changes induced by a motor-imposed ramp were accompanied by corresponding sarcomere-length changes. However, the sarcomere-length changes were stepwise. Computer analysis of the stepwise shortening patterns revealed a step-size distribution containing multiple peaks. In the activated state, the peaks were separated by 2.7 nm per half-sarcomere which is the linear actin-subunit spacing. Thus, translation steps are an integer multiple of the actin-subunit spacing. This result parallels the one observed in the kinesin-tubulin spacing, where step size is a multiple of the tubulin-subunit spacing. In the muscle system, however, the steps are preserved on a macroscopic scale, implying high synchrony. The quantal steps are easily explained by a model in which the actin filament propels itself over stationary cross-bridges: if actin binds to the cross-bridges between steps, then the observed quantal result is inevitable. As probes of contractile phenomena approach the molecular level, the discrete unitary events underlying contraction begin to emerge. Thus, step-like behavior is observed as the single kinesin molecule translates along the microtubule, as the single myosin molecule translates over the actin filament, and as the single isolated titin molecule is stretched.
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Affiliation(s)
- G H Pollack
- Department of Bioengineering, University of Washington, Seattle 98195, USA
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26
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Corish J, Morton-Blake DA. An Atomic-Scale Simulation of Lubricated Motion. MOLECULAR SIMULATION 1998. [DOI: 10.1080/08927029808022049] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Klein J, Kumacheva E. Simple liquids confined to molecularly thin layers. I. Confinement-induced liquid-to-solid phase transitions. J Chem Phys 1998. [DOI: 10.1063/1.476114] [Citation(s) in RCA: 423] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Kumacheva E, Klein J. Simple liquids confined to molecularly thin layers. II. Shear and frictional behavior of solidified films. J Chem Phys 1998. [DOI: 10.1063/1.476115] [Citation(s) in RCA: 199] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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Gupta SA, Cochran HD, Cummings PT. Shear behavior of squalane and tetracosane under extreme confinement. II. Confined film structure. J Chem Phys 1997. [DOI: 10.1063/1.474172] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Peters GH, Tildesley DJ. Computer simulation of the rheology of grafted chains under shear. II. Depletion of chains at the wall. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1996; 54:5493-5501. [PMID: 9965735 DOI: 10.1103/physreve.54.5493] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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31
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Bordarier P, Rousseau B, Fuchs AH. Solvation Force and Confinement-Induced Phase Transitions of Model Ultra Thin Films. MOLECULAR SIMULATION 1996. [DOI: 10.1080/08927029608024109] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Schmidt M, Löwen H. Freezing between two and three dimensions. PHYSICAL REVIEW LETTERS 1996; 76:4552-4555. [PMID: 10061320 DOI: 10.1103/physrevlett.76.4552] [Citation(s) in RCA: 136] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Abstract
The liquid-to-solid transition of a simple model liquid confined between two surfaces was studied as a function of surface separation. From large surface separations (more than 1000 angstroms) down to a separation corresponding to seven molecular layers, the confined films displayed a liquid-like shear viscosity. When the surface separation was further decreased by a single molecular spacing, the films underwent an abrupt, reversible transition to a solid. At the transition, the rigidity of the confined films (quantified in terms of an "effective viscosity") increased reversibly by at least seven orders of magnitude.
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Peters GH, Tildesley DJ. Computer simulation of the rheology of grafted chains under shear. PHYSICAL REVIEW. E, STATISTICAL PHYSICS, PLASMAS, FLUIDS, AND RELATED INTERDISCIPLINARY TOPICS 1995; 52:1882-1890. [PMID: 9963608 DOI: 10.1103/physreve.52.1882] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Bhushan B, Israelachvili JN, Landman U. Nanotribology: friction, wear and lubrication at the atomic scale. Nature 1995. [DOI: 10.1038/374607a0] [Citation(s) in RCA: 1325] [Impact Index Per Article: 45.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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