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Hähl H, Griffo A, Safaridehkohneh N, Heppe J, Backes S, Lienemann M, Linder MB, Santen L, Laaksonen P, Jacobs K. Dynamic Assembly of Class II Hydrophobins from T. reesei at the Air-Water Interface. Langmuir 2019; 35:9202-9212. [PMID: 31268722 DOI: 10.1021/acs.langmuir.9b01078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Class II hydrophobins are amphiphilic proteins produced by filamentous fungi. One of their typical features is the tendency to accumulate at the interface between an aqueous phase and a hydrophobic phase, such as the air-water interface. The kinetics of the interfacial self-assembly of wild-type hydrophobins HFBI and HFBII and some of their engineered variants at the air-water interface were measured by monitoring the accumulated mass at the interface via nondestructive ellipsometry measurements. The resulting mass vs time curves revealed unusual kinetics for a monolayer formation that did not follow a typical Langmuir-type of behavior but had a rather coverage-independent rate instead. Typically, the full surface coverage was obtained at masses corresponding to a monolayer. The formation of multilayers was not observed. Atomic force microscopy revealed formation and growth of non-fusing protein clusters at the interface. The mechanism of the adsorption was studied by varying the structure or charges of the protein or the ionic strength of the subphase, revealing that the lateral interactions between the hydrophobins play a role in their interfacial assembly. Additionally, a theoretical model was introduced to identify the underlying mechanism of the unconventional adsorption kinetics.
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Affiliation(s)
| | - Alessandra Griffo
- Department of Bioproducts and Biosystems , Aalto University , P.O. Box 16100, FI-00076 Aalto , Finland
| | | | | | - Sebastian Backes
- Federal Institute for Material Research and Testing (BAM) , Unter den Eichen 87 , 12205 Berlin , Germany
| | - Michael Lienemann
- VTT Technical Research Centre of Finland Ltd. , Espoo 02150 , Finland
| | - Markus B Linder
- Department of Bioproducts and Biosystems , Aalto University , P.O. Box 16100, FI-00076 Aalto , Finland
| | | | - Päivi Laaksonen
- Department of Bioproducts and Biosystems , Aalto University , P.O. Box 16100, FI-00076 Aalto , Finland
- HAMK Tech, Häme University of Applied Sciences , P.O. Box 230, Hämeenlinna 13101 , Finland
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Witt MU, Hinrichs S, Möller N, Backes S, Fischer B, von Klitzing R. Distribution of CoFe2O4 Nanoparticles Inside PNIPAM-Based Microgels of Different Cross-linker Distributions. J Phys Chem B 2019; 123:2405-2413. [DOI: 10.1021/acs.jpcb.8b09236] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marcus U. Witt
- Department of Physics, Soft Matter at Interfaces, Technical University Darmstadt, Alarich-Weiss-Straße 10, 64287 Darmstadt, Germany
| | - Stephan Hinrichs
- Institute of Physical Chemistry, University Hamburg, Grindelallee 117, 20146 Hamburg, Germany
| | - Nadir Möller
- Department of Physics, Soft Matter at Interfaces, Technical University Darmstadt, Alarich-Weiss-Straße 10, 64287 Darmstadt, Germany
| | - Sebastian Backes
- Stranski-Laboratories of Physical and Theoretical Chemistry, Technical University Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Birgit Fischer
- Institute of Physical Chemistry, University Hamburg, Grindelallee 117, 20146 Hamburg, Germany
| | - Regine von Klitzing
- Department of Physics, Soft Matter at Interfaces, Technical University Darmstadt, Alarich-Weiss-Straße 10, 64287 Darmstadt, Germany
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Backes S, Von Klitzing R. Nanomechanics and Nanorheology of Microgels at Interfaces. Polymers (Basel) 2018; 10:E978. [PMID: 30960903 PMCID: PMC6404016 DOI: 10.3390/polym10090978] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 08/19/2018] [Accepted: 08/20/2018] [Indexed: 11/16/2022] Open
Abstract
The review addresses nanomechanics and nanorheology of stimuli responsive microgels adsorbed at an interface. In order to measure the mechanical properties on a local scale, an atomic force microscope is used. The tip presents an indenter with a radius of curvature of a few 10 s of nm. Static indentation experiments and dynamic studies with an excited cantilever are presented. The effect of several internal and external parameters on the mechanical properties is reviewed. The focus is on the correlation between the swelling abilities of the gels and their mechanical properties. Several results are surprising and show that the relationship is not as simple as one might expect.
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Affiliation(s)
- Sebastian Backes
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin, Strasse des 17. Juni 124, D⁻10623 Berlin, Germany.
| | - Regine Von Klitzing
- Soft Matter at Interfaces, Department of Physics, TU Darmstadt, Alarich-Weiss-Strasse 10, D⁻62487 Darmstadt, Germany.
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Backes S, Krause P, Tabaka W, Witt MU, von Klitzing R. Combined Cononsolvency and Temperature Effects on Adsorbed PNIPAM Microgels. Langmuir 2017; 33:14269-14277. [PMID: 29166032 DOI: 10.1021/acs.langmuir.7b02903] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The present study addresses the multiresponsive behavior of poly(N-isopropylacrylamide) (PNIPAM) microgels adsorbed to interfaces. The microgels react to changes in temperature by shrinking in aqueous solution above their volume phase transition temperature (VPTT). Additionally, they shrink in mixtures of water and ethanol, although both individual liquids are good solvents for PNIPAM. The combination of this so-called cononsolvency effect and the temperature response of adsorbed microgels is studied by atomic force microscopy (AFM). Adsorbed microgels are of special interest because they are compressed considerably compared to those in bulk solution. It is shown that the impact of adsorption on swelling depends on the specific surface details, as well as the sample preparation. Thereby, the microgels are deposited on two different kinds of surfaces: on gold surface and on polycation (PAH) coating which show different interactions with the microgels in terms of electrostatic interaction and wettability. In addition, the microgels were deposited from different solvent mixtures. This influences the microgel structure and thereby the swelling properties. Nanorheology studies by dynamic AFM measurements lead to surprising results which are explained by the fact that not only polymer density but a subtle interaction between polymer and solvent might dominate the rheological properties. This work supports the view that preferential adsorption of ethanol at PNIPAM drives cononsolvency, while the shrinking at T > VPTT is caused by general breaking of hydrogen bonds between solvents and PNIPAM.
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Affiliation(s)
- Sebastian Backes
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany
- Institut für Physik, Technische Universität Darmstadt , Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
| | - Patrick Krause
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Weronika Tabaka
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Marcus U Witt
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany
- Institut für Physik, Technische Universität Darmstadt , Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
| | - Regine von Klitzing
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany
- Institut für Physik, Technische Universität Darmstadt , Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
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Backes S, Krause P, Tabaka W, Witt MU, Mukherji D, Kremer K, von Klitzing R. Poly( N-isopropylacrylamide) Microgels under Alcoholic Intoxication: When a LCST Polymer Shows Swelling with Increasing Temperature. ACS Macro Lett 2017; 6:1042-1046. [PMID: 35650939 DOI: 10.1021/acsmacrolett.7b00557] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Poly(N-isopropylacrylamide) (PNIPAM) microgel is a smart polymer that shows a volume phase transition temperature (VPTT) at around 32 °C in aqueous solutions, above which it collapses. In this work, combining experiments and molecular simulations, it is shown that PNIPAM microgels do not always exhibit a collapsed structure above the VPTT. Instead, PNIPAM in aqueous alcohol mixtures shows a two-step conformational transition, i.e., a collapse at low temperatures (T < 32 °C) and a reswelling when T > 50 °C. The present analysis indicates that delicate microscopic interaction details, together with the bulk solution properties, play a key role in dictating the reswelling behavior. Even when PNIPAM microgels swell with increasing T, this is not a standard upper critical solution behavior.
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Affiliation(s)
- Sebastian Backes
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
- Institut
für Physik, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
| | - Patrick Krause
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Weronika Tabaka
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Marcus U. Witt
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
- Institut
für Physik, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
| | - Debashish Mukherji
- Max-Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Kurt Kremer
- Max-Planck Institut für Polymerforschung, Ackermannweg 10, 55128 Mainz, Germany
| | - Regine von Klitzing
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
- Institut
für Physik, Technische Universität Darmstadt, Alarich-Weiss-Strasse 10, 64287 Darmstadt, Germany
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Wang W, Xu Y, Han H, Micciulla S, Backes S, Li A, Xu J, Shen W, von Klitzing R, Guo X. Odd-even effect during layer-by-layer assembly of polyelectrolytes inspired by marine mussel. ACTA ACUST UNITED AC 2016. [DOI: 10.1002/polb.24266] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Weina Wang
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; Shanghai 200237 People's Republic of China
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin; Berlin D-10623 Germany
| | - Yisheng Xu
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; Shanghai 200237 People's Republic of China
| | - Haoya Han
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; Shanghai 200237 People's Republic of China
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin; Berlin D-10623 Germany
| | - Samantha Micciulla
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin; Berlin D-10623 Germany
| | - Sebastian Backes
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin; Berlin D-10623 Germany
| | - Ang Li
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; Shanghai 200237 People's Republic of China
| | - Jun Xu
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; Shanghai 200237 People's Republic of China
| | - Weihua Shen
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; Shanghai 200237 People's Republic of China
| | - Regine von Klitzing
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin; Berlin D-10623 Germany
| | - Xuhong Guo
- State Key Laboratory of Chemical Engineering; East China University of Science and Technology; Shanghai 200237 People's Republic of China
- Engineering Research Center of Materials Chemical Engineering of Xinjiang Bintuan; Shihezi University; Xinjiang 832000 People's Republic of China
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Chernenkaya A, Morherr A, Backes S, Popp W, Witt S, Kozina X, Nepijko SA, Bolte M, Medjanik K, Öhrwall G, Krellner C, Baumgarten M, Elmers HJ, Schönhense G, Jeschke HO, Valentí R. Microscopic origin of the charge transfer in single crystals based on thiophene derivatives: A combined NEXAFS and density functional theory approach. J Chem Phys 2016; 145:034702. [PMID: 27448899 DOI: 10.1063/1.4958659] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Affiliation(s)
- A. Chernenkaya
- Graduate School Materials Science in Mainz, 55128 Mainz, Germany
- Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany
| | - A. Morherr
- Physikalisches Institut, Goethe-Universität, 60438 Frankfurt am Main, Germany
| | - S. Backes
- Institut für Theoretische Physik, Goethe-Universität, 60438 Frankfurt am Main, Germany
| | - W. Popp
- Institut für Theoretische Physik, Goethe-Universität, 60438 Frankfurt am Main, Germany
| | - S. Witt
- Physikalisches Institut, Goethe-Universität, 60438 Frankfurt am Main, Germany
| | - X. Kozina
- Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany
| | - S. A. Nepijko
- Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany
| | - M. Bolte
- Institut für Anorganische Chemie, Goethe-Universität, 60438 Frankfurt am Main, Germany
| | - K. Medjanik
- MAX-IV Laboratory, Lund University, 22100 Lund, Sweden
| | - G. Öhrwall
- MAX-IV Laboratory, Lund University, 22100 Lund, Sweden
| | - C. Krellner
- Physikalisches Institut, Goethe-Universität, 60438 Frankfurt am Main, Germany
| | - M. Baumgarten
- Max-Planck-Institut für Polymerforschung, 55021 Mainz, Germany
| | - H. J. Elmers
- Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany
| | - G. Schönhense
- Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany
| | - H. O. Jeschke
- Institut für Theoretische Physik, Goethe-Universität, 60438 Frankfurt am Main, Germany
| | - R. Valentí
- Institut für Theoretische Physik, Goethe-Universität, 60438 Frankfurt am Main, Germany
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Wang W, Xu Y, Backes S, Li A, Micciulla S, Kayitmazer AB, Li L, Guo X, von Klitzing R. Construction of Compact Polyelectrolyte Multilayers Inspired by Marine Mussel: Effects of Salt Concentration and pH As Observed by QCM-D and AFM. Langmuir 2016; 32:3365-74. [PMID: 27007179 DOI: 10.1021/acs.langmuir.5b04706] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Biomimetic multilayers based on layer-by-layer (LbL) assembly were prepared as functional films with compact structure by incorporating the mussel-inspired catechol cross-linking. Dopamine-modified poly(acrylic acid) (PAADopa) was synthesized as a polyanion to offer electrostatic interaction with the prelayer polyethylenimine (PEI) and consecutively cross-linked by zinc to generate compact multilayers with tunable physicochemical properties. In situ layer-by-layer growth and cross-linking were monitored by a quartz crystal microbalance with dissipation (QCM-D) to reveal the kinetics of the process and the influence of Dopa chemistry. Addition of Dopa enhanced the mass adsorption and led to the formation of a more compact structure. An increase of ionic strength induced an increase in mass adsorption in the Dopa-cross-linked multilayers. This is a universal approach for coating of various surfaces such as Au, SiO2, Ti, and Al2O3. Roughness observed by AFM in both wet and dry conditions was compared to confirm the compact morphology of Dopa-cross-linked multilayers. Because of the pH sensitivity of Dopa moiety, metal-chelated Dopa groups can be turned into softer structure at higher pH as revealed by reduction of Young's modulus determined by MFP-3D AFM. A deeper insight into the growth and mechanical properties of Dopa-cross-linked polyelectrolyte multilayers was addressed in the present study. This allows a better control of these systems for bioapplications.
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Affiliation(s)
- Weina Wang
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany
| | - Yisheng Xu
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China
| | - Sebastian Backes
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany
| | - Ang Li
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China
| | - Samantha Micciulla
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany
| | - A Basak Kayitmazer
- Chemistry Department, Bogazici University , Bebek, Istanbul 34342, Turkey
| | - Li Li
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China
| | - Xuhong Guo
- State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China
- Engineering Research Center of Materials Chemical Engineering of Xinjiang Bintuan, Shihezi University , Xinjiang 832000, China
| | - Regine von Klitzing
- Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany
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Backes S, Witt MU, Roeben E, Kuhrts L, Aleed S, Schmidt AM, von Klitzing R. Loading of PNIPAM Based Microgels with CoFe2O4 Nanoparticles and Their Magnetic Response in Bulk and at Surfaces. J Phys Chem B 2015; 119:12129-37. [DOI: 10.1021/acs.jpcb.5b03778] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sebastian Backes
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Marcus U. Witt
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Eric Roeben
- Department
für Chemie, Institut für Physikalische Chemie, Universität zu Köln, Luxemburger Str. 116, 50939 Köln, Germany
| | - Lucas Kuhrts
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Sarah Aleed
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
| | - Annette M. Schmidt
- Department
für Chemie, Institut für Physikalische Chemie, Universität zu Köln, Luxemburger Str. 116, 50939 Köln, Germany
| | - Regine von Klitzing
- Stranski-Laboratorium
für Physikalische und Theoretische Chemie, Technische Universität Berlin, Straße des 17. Juni 124, 10623 Berlin, Germany
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McGraw JD, Bäumchen O, Klos M, Haefner S, Lessel M, Backes S, Jacobs K. Nanofluidics of thin polymer films: linking the slip boundary condition at solid-liquid interfaces to macroscopic pattern formation and microscopic interfacial properties. Adv Colloid Interface Sci 2014; 210:13-20. [PMID: 24780402 DOI: 10.1016/j.cis.2014.03.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Revised: 03/28/2014] [Accepted: 03/28/2014] [Indexed: 10/25/2022]
Abstract
If a thin liquid film is not stable, different rupture mechanisms can be observed causing characteristic film morphologies: spinodal dewetting and dewetting by nucleation of holes. This rupturing entails liquid flow and opens new possibilities to study microscopic phenomena. Here we use this process of dewetting to gain insight on the slip boundary condition at the solid-liquid interface. Having established hydrodynamic models that allow for the determination of the slip length in a dewetting experiment based on nucleation, we move on to the quantification and molecular description of slip effects in various systems. For the late stage of the dewetting process involving the Rayleigh-Plateau instability, several distinct droplet patterns can be observed. We describe the importance of slip in determining what pattern may be found. In order to control the slip length, we use polymeric liquids on different hydrophobic coatings of silicon wafers. We find that subtle changes in the coating can lead to large changes in the slip length. Thus, we gain insight into the question of how the structure of the substrate affects the slip length.
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Affiliation(s)
- A W Cornelissen
- Max-Planck-Institut für Biologie, Molecular Parasitology Unit, Tübingen, F.R.G
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