1
|
Tang Y, Liu Y, Zhang D, Zheng J. Perspectives on Theoretical Models and Molecular Simulations of Polymer Brushes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:1487-1502. [PMID: 38153400 DOI: 10.1021/acs.langmuir.3c03253] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Polymer brushes have witnessed extensive utilization and progress, driven by their distinct attributes in surface modification, tethered group functionality, and tailored interactions at the nanoscale, enabling them for various scientific and industrial applications of coatings, sensors, switchable/responsive materials, nanolithography, and lab-on-a-chips. Despite the wealth of experimental investigations into polymer brushes, this review primarily focuses on computational studies of antifouling polymer brushes with a strong emphasis on achieving a molecular-level understanding and structurally designing antifouling polymer brushes. Computational exploration covers three realms of thermotical models, molecular simulations, and machine-learning approaches to elucidate the intricate relationship between composition, structure, and properties concerning polymer brushes in the context of nanotribology, surface hydration, and packing conformation. Upon acknowledging the challenges currently faced, we extend our perspectives toward future research directions by delineating potential avenues and unexplored territories. Our overarching objective is to advance our foundational comprehension and practical utilization of polymer brushes for antifouling applications, leveraging the synergy between computational methods and materials design to drive innovation in this crucial field.
Collapse
Affiliation(s)
- Yijing Tang
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Yonglan Liu
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
| | - Dong Zhang
- The Wallace H. Coulter Department of Biomedical Engineering at Georgia Tech and Emory University, Georgia Institute of Technology, Atlanta, Georgia 30332, United States
| | - Jie Zheng
- Department of Chemical, Biomolecular, and Corrosion Engineering, The University of Akron, Akron, Ohio 44325, United States
| |
Collapse
|
2
|
Qiao Y, He Q, Huang HH, Mastropietro D, Jiang Z, Zhou H, Liu Y, Tirrell MV, Chen W. Stretching of immersed polyelectrolyte brushes in shear flow. NANOSCALE 2023; 15:19282-19291. [PMID: 37997161 DOI: 10.1039/d3nr04187e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2023]
Abstract
The way that polymer brushes respond to shear flow has important implications in various applications, including antifouling, corrosion protection, and stimuli-responsive materials. However, there is still much to learn about the behaviours and mechanisms that govern these responses. To address this gap in knowledge, our study uses in situ X-ray reflectivity to investigate how poly(styrene sulfonate) (PSS) brushes stretch and change in different environments, such as isopropanol (a poor solvent), water (a good solvent), and aqueous solutions containing various cations (Cs+, Ba2+, La3+, and Y3+). We have designed a custom apparatus that exposes the PSS brushes to both tangential shear forces from the primary flow and upward drag forces from a secondary flow. Our experimental findings clearly show that shear forces have a significant impact on how the chains in PSS brushes are arranged. At low shear rates, the tangential shear force causes the chains to tilt, leading to brush contraction. In contrast, higher shear rates generate an upward shear force that stretches and expands the chains. By analysing electron density profiles obtained from X-ray reflectivity, we gain valuable insights into how the PSS brushes respond structurally, especially the role of the diffuse layer in this dynamic behaviour. Our results highlight the importance of the initial chain configuration, which is influenced by the solvent and cations present, in shaping how polymer brushes respond to shear flow. The strength of the salt bridge network also plays a crucial role in determining how easily the brushes can stretch, with stronger networks offering more resistance to stretching. Ultimately, our study aims to enhance our understanding of polymer physics at interfaces, with a particular focus on practical applications involving polymer brushes.
Collapse
Affiliation(s)
- Yijun Qiao
- Materials Science Division and Centre for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA.
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
| | - Qiming He
- Materials Science Division and Centre for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA.
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA
| | - Hsin-Hsiang Huang
- Materials Science Division and Centre for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA.
| | - Dean Mastropietro
- Materials Science Division and Centre for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA.
| | - Zhang Jiang
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Hua Zhou
- X-ray Science Division, Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Yuhong Liu
- State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China.
| | - Matthew V Tirrell
- Materials Science Division and Centre for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA.
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA
| | - Wei Chen
- Materials Science Division and Centre for Molecular Engineering, Argonne National Laboratory, Lemont, Illinois 60439, USA.
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, 60637, USA
| |
Collapse
|
3
|
Chen L, Jiang F, Xu H, Fan Y, Du C. Improved membrane stability of alginate-chitosan microcapsules by crosslinking with tannic acid. Biotechnol Lett 2023:10.1007/s10529-023-03399-3. [PMID: 37266880 DOI: 10.1007/s10529-023-03399-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 04/01/2023] [Accepted: 05/16/2023] [Indexed: 06/03/2023]
Abstract
OBJECTIVE The insufficient stability of alginate-chitosan (ALG-CS) microcapsules in biorelevant media limits their applications in the biomedical field. Attempts were made to improve the membrane stability of ALG-CS microcapsules by noncovalent crosslinking with tannic acid. RESULTS The membrane stability of ALG-CS microcapsules in culture medium and serum was significantly improved by crosslinking with tannic acid. Moreover, the reason for the significant improvement in membrane stability had been demonstrated to be that the stability of chitosan-tannic acid (CS-TA) polyelectrolyte complexes was less affected by the competitive binding of those weak acid ions such as HCO3-. In addition, the optimal conditions for preparing alginate-chitosan-tannic acid (ALG-CS-TA) microcapsules were tannic acid concentration of 0.5% (w/v) and pH = 7. CONCLUSION The study provides a novel approach for improving the stability of the ALG-CS microcapsules in biorelevant media to expand their scope of application in the biological field.
Collapse
Affiliation(s)
- Li Chen
- College of Pharmaceutical Science, Zhejiang University, Hangzhou, 310058, Zhejiang, People's Republic of China.
- School of Pharmaceutical and Chemical Engineering, Taizhou University, No. 1139, Shifu Avenue, Jiaojiang District, Taizhou, 318000, Zhejiang, People's Republic of China.
| | - Fang Jiang
- School of Pharmaceutical and Chemical Engineering, Taizhou University, No. 1139, Shifu Avenue, Jiaojiang District, Taizhou, 318000, Zhejiang, People's Republic of China
| | - Haidan Xu
- School of Pharmaceutical and Chemical Engineering, Taizhou University, No. 1139, Shifu Avenue, Jiaojiang District, Taizhou, 318000, Zhejiang, People's Republic of China
| | - Yaoyao Fan
- School of Pharmaceutical and Chemical Engineering, Taizhou University, No. 1139, Shifu Avenue, Jiaojiang District, Taizhou, 318000, Zhejiang, People's Republic of China
| | - Cunbin Du
- School of Pharmaceutical and Chemical Engineering, Taizhou University, No. 1139, Shifu Avenue, Jiaojiang District, Taizhou, 318000, Zhejiang, People's Republic of China
| |
Collapse
|
4
|
Khakzad F, Dewangan NK, Li TH, Safi Samghabadi F, Herrera Monegro R, Robertson ML, Conrad JC. Fouling Resistance and Release Properties of Poly(sulfobetaine) Brushes with Varying Alkyl Chain Spacer Lengths and Molecular Weights. ACS APPLIED MATERIALS & INTERFACES 2023; 15:2009-2019. [PMID: 36533943 DOI: 10.1021/acsami.2c16417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
We examined the effects of alkyl carbon spacer length (CSL) and molecular weight on fouling resistance and release properties of zwitterionic poly(sulfobetaine methacrylate) brushes. Using surface-initiated atom transfer radical polymerization, we synthesized two series of brushes with CSL = 3 and 4 and molecular weight from 19 to 1500 kg ·mol-1, corresponding to dry brush thickness from around 6 to 180 nm. The brush with CSL = 3 was nearly completely wet with water (independent of molecular weight), whereas the brush with CSL = 4 exhibited a strong increase in water contact angle with molecular weight. Though the two-brush series had distinct wetting properties, both series of brushes exhibited similarly great resistance against fouling by Staphylococcus epidermidis bacteria and Aspergillus niger fungi spores when submerged in water, indicating that neither molecular weight nor CSL strongly affected the antifouling behavior. We also compared the efficacy of brushes against fouling by fungi and silicon oil in air. Brushes grafted to filter paper were strongly fouled by fungi and silicon oil in air. Grafting the polymers to the filter paper, however, greatly enhanced removal of the foulant upon rinsing. The removal of fungi and silicon oil when rinsed with a salt solution was enhanced by 219 and 175%, respectively, as compared to a blank filter paper control. Thus, our results indicate that these zwitterionic brushes can promote foulant removal for dry applications in addition to their well-known fouling resistance in submerged conditions.
Collapse
Affiliation(s)
- Fahimeh Khakzad
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Narendra K Dewangan
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Tzu-Han Li
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Farshad Safi Samghabadi
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Ronard Herrera Monegro
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Megan L Robertson
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| | - Jacinta C Conrad
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas77204, United States
| |
Collapse
|
5
|
Yao Y, Zhu YL, Ma X, Zhou J. Interactions on Proteins Arising from the Self-Assembly of a Polyelectrolyte Brush. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:7759-7765. [PMID: 35709429 DOI: 10.1021/acs.langmuir.2c00801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Surfaces grafted with polyelectrolyte chains for excellent performance in protein antifouling are highly desired in many applications, such as biomedical implants and devices. In general, the adsorbing/resisting behaviors of proteins can be mainly attributed to the electrostatic interactions that are associated with the charge properties of proteins and polyelectrolytes. By coarse-grained molecular dynamics simulations, we examined the self-assembled structures of polyanion and polyzwitterion brushes as well as the interactions on negatively and positively charged proteins. We found that in addition to charges, the structural polarization induced by self-assembly with a certain charge distribution shows significant influences on protein behavior. The large-scale dipole-dipole interactions between brushes and proteins can dominate the behavior of proteins on the brushes under certain circumstances. To ensure simulation accuracy, we compared two models and found a polar Martini model that explicitly treats electrostatic interactions as long-ranged ones, giving a more reasonable structural description compared with the normal Martini model that truncates electrostatic interactions.
Collapse
Affiliation(s)
- Yunming Yao
- Department of Dermatology and Venereology, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| | - You-Liang Zhu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China
| | - Xiaoyuan Ma
- Jilin Provincial Center for Animal Disease Control and Prevention, Changchun 130062, China
| | - Junfeng Zhou
- Department of Dermatology and Venereology, The First Hospital of Jilin University, Changchun, Jilin 130021, China
| |
Collapse
|
6
|
Li D, Xu L, Wang J, Gautrot JE. Responsive Polymer Brush Design and Emerging Applications for Nanotheranostics. Adv Healthc Mater 2021; 10:e2000953. [PMID: 32893474 DOI: 10.1002/adhm.202000953] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/11/2020] [Indexed: 12/29/2022]
Abstract
Responsive polymer brushes are a category of polymer brushes that are capable of conformational and chemical changes in response to external stimuli. They offer unique opportunities for the control of bio-nano interactions due to the precise control of chemical and structural parameters such as the brush thickness, density, chemistry, and architecture. The design of responsive brushes at the surface of nanomaterials for theranostic applications has developed rapidly. These coatings can be generated from a very broad range of nanomaterials, without compromising their physical, photophysical, and imaging properties. Although the use of responsive brushes for nanotheranostic remains in its early stages, in this review, the aim is to present how the systems developed to date can be combined to control sensing, imaging, and controlled delivery of therapeutics. The recent developments for such design and associated methods for the synthesis of responsive brushes are discussed. The responsive behaviors of homo polymer brushes and brushes with more complex architectures are briefly reviewed, before the applications of responsive brushes as smart delivery systems are discussed. Finally, the recent work is summarized on the use of responsive polymer brushes as novel biosensors and diagnostic tools for the detection of analytes and biomarkers.
Collapse
Affiliation(s)
- Danyang Li
- School of Cancer and Pharmaceutical Sciences King's College London 150 Stamford Street London SE1 9NH UK
- Institute of Bioengineering Queen Mary University of London Mile End Road London E1 4NS UK
- School of Engineering and Materials Science Queen Mary University of London Mile End Road London E1 4NS UK
| | - Lizhou Xu
- Department of Materials Imperial College London London SW7 2AZ UK
| | - Jing Wang
- School of Life Sciences Northwestern Polytechnical University Xi'an 710072 China
| | - Julien E. Gautrot
- Institute of Bioengineering Queen Mary University of London Mile End Road London E1 4NS UK
- School of Engineering and Materials Science Queen Mary University of London Mile End Road London E1 4NS UK
| |
Collapse
|
7
|
Photoinduced self-initiated graft polymerization of methacrylate monomers on poly(ether ether ketone) substrates and surface parameters for controlling cell adhesion. Polym J 2020. [DOI: 10.1038/s41428-020-0318-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
|
8
|
Delcea M, Helm CA. X-ray and Neutron Reflectometry of Thin Films at Liquid Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:8519-8530. [PMID: 30901219 DOI: 10.1021/acs.langmuir.8b04315] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In the 1980s, Helmuth Möhwald studied lipid monolayers at the air/water interface to understand the thermodynamically characterized phases at the molecular level. In collaboration with Jens Als-Nielsen, X-ray reflectometry was used and further developed to determine the electron density profile perpendicular to the water surface. Using a slab model, parameters such as thickness and density of the individual molecular regions, as well as the roughness of the individual interfaces, were determined. Later, X-ray and neutron reflectometry helped to understand the coverage and conformation of anchored and adsorbed polymers. Nowadays, they resolve molecular properties in emerging topics such as liquid metals and ionic liquids. Much is still to be learned about buried interfaces (e.g., liquid/liquid interfaces). In this Article, a historical and theoretical background of X-ray reflectivity is given, recent developments of X-ray and neutron reflectometry for polymers at interfaces and thin layers are highlighted, and emerging research topics involving these techniques are emphasized.
Collapse
Affiliation(s)
- Mihaela Delcea
- Institute of Biochemistry , University of Greifswald , Felix-Hausdorff-Straße 4 , 17489 Greifswald , Germany
- ZIK HIKE- Zentrum für Innovationskompetenz , Humorale Immunreaktionen bei kardiovaskulären Erkrankungen , Fleischmannstraße 42 , 17489 Greifswald , Germany
| | - Christiane A Helm
- Institute of Physics , University of Greifswald , Felix-Hausdorff-Straße 4 , 17489 Greifswald , Germany
| |
Collapse
|
9
|
Zhu YL, Lu ZY, Li ZW, Sun ZY, Liu X. Effect of the Self-Assembled Structures of Hydrated Polyzwitterionic and Polyanionic Brushes on Their Self-Cleaning Capabilities. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:6669-6675. [PMID: 31034239 DOI: 10.1021/acs.langmuir.9b00714] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The capability of polyelectrolyte brushes to spontaneously clean oil fouling via water is determined by factors including water wettability and the self-assembled structures of hydrated polyelectrolytes. Although the charged groups of polyelectrolytes provide the original source of water wettability, the self-assembled structures play a significant role in the self-cleaning performances. Here, we employ coarse-grained molecular dynamics simulations to study the general self-cleaning characteristics of two types of surface-grafted polyelectrolyte brushes (i.e., zwitterionic and anionic polyelectrolytes). It has been found that the high grafting density is favorable to fouling reduction for both polyzwitterions and polyanions. To be specific, the hydrated polyzwitterions form an intermolecular cross-linked network via zwitterionic complexes, resulting in better self-cleaning capabilities than the polyanions at lower grafting densities. However, polyanions form bundles with each consisting of several chains via hydrophobic interactions and electrostatic repulsions presenting better self-cleaning performances than the polyzwitterions at higher grafting densities.
Collapse
Affiliation(s)
- You-Liang Zhu
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
- University of Science and Technology of China , Hefei 230026 , China
| | | | - Zhan-Wei Li
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
- University of Science and Technology of China , Hefei 230026 , China
| | - Zhao-Yan Sun
- State Key Laboratory of Polymer Physics and Chemistry , Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022 , China
- University of Science and Technology of China , Hefei 230026 , China
| | | |
Collapse
|
10
|
Zhang Q, Ran Q, Shu X, Yang Y, Yu C. Effect of counter-ions on the solution conformation and adsorption behaviors of comb-like polycarboxylates on calcium carbonate. J DISPER SCI TECHNOL 2019. [DOI: 10.1080/01932691.2018.1542313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Qian Zhang
- State Key Laboratory of High Performance Civil Engineering Materials (HPCEM), Jiangsu Research Institute of Building Science, Nanjing, Jiangsu, China
- Jiangsu Sobute New Materials Co. Ltd, Nanjing, Jiangsu, China
| | - Qianping Ran
- State Key Laboratory of High Performance Civil Engineering Materials (HPCEM), Jiangsu Research Institute of Building Science, Nanjing, Jiangsu, China
- Jiangsu Sobute New Materials Co. Ltd, Nanjing, Jiangsu, China
| | - Xin Shu
- State Key Laboratory of High Performance Civil Engineering Materials (HPCEM), Jiangsu Research Institute of Building Science, Nanjing, Jiangsu, China
- Jiangsu Sobute New Materials Co. Ltd, Nanjing, Jiangsu, China
| | - Yong Yang
- State Key Laboratory of High Performance Civil Engineering Materials (HPCEM), Jiangsu Research Institute of Building Science, Nanjing, Jiangsu, China
- Jiangsu Sobute New Materials Co. Ltd, Nanjing, Jiangsu, China
| | - Cheng Yu
- State Key Laboratory of High Performance Civil Engineering Materials (HPCEM), Jiangsu Research Institute of Building Science, Nanjing, Jiangsu, China
- Jiangsu Sobute New Materials Co. Ltd, Nanjing, Jiangsu, China
| |
Collapse
|
11
|
Santos DES, Li D, Ramstedt M, Gautrot JE, Soares TA. Conformational Dynamics and Responsiveness of Weak and Strong Polyelectrolyte Brushes: Atomistic Simulations of Poly(dimethyl aminoethyl methacrylate) and Poly(2-(methacryloyloxy)ethyl trimethylammonium chloride). LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:5037-5049. [PMID: 30869897 DOI: 10.1021/acs.langmuir.8b04268] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
The complex solution behavior of polymer brushes is key to control their properties, including for biomedical applications and catalysis. The swelling behavior of poly(dimethyl aminoethyl methacrylate) (PDMAEMA) and poly(2-(methacryloyloxy)ethyl trimethylammonium chloride) (PMETAC) in response to changes in pH, solvent, and salt types has been investigated using atomistic molecular dynamics simulations. PDMAEMA and PMETAC have been selected as canonical models for weak and strong polyelectrolytes whose complex conformational behavior is particularly challenging for the development and validation of atomistic models. The GROMOS-derived atomic parameters reproduce the experimental swelling coefficients obtained from ellipsometry measurements for brushes of 5-15 nm thickness. The present atomistic models capture the protonated morphology of PDMAEMA, the swollen and collapsed conformations of PDMAEMA and PMETAC in good and bad solvents, and the salt-selective response of PMETAC. The modular nature of the molecular models allows for the simple extension of atomic parameters to a variety of polymers or copolymers.
Collapse
Affiliation(s)
- Denys E S Santos
- Departamento de Química Fundamental , Universidade Federal de Pernambuco , Cidade Universitária, 50670-901 Recife , Brazil
| | | | | | | | - Thereza A Soares
- Departamento de Química Fundamental , Universidade Federal de Pernambuco , Cidade Universitária, 50670-901 Recife , Brazil
- Department of Chemistry , Umeå University , 90187 Umeå , Sweden
| |
Collapse
|
12
|
Shiomoto S, Yamaguchi K, Kobayashi M. Time Evolution of Precursor Thin Film of Water on Polyelectrolyte Brush. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:10276-10286. [PMID: 30102545 DOI: 10.1021/acs.langmuir.8b02070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The microscopic wetting behavior of a water film on the line-patterned surface of a polyelectrolyte brush was directly visualized using an optical microscope by dyeing procedures. Surface line patterns of 5 and 5 μm width or 10 and 5 μm width for the polyelectrolyte brush and hydrophobic monolayer, respectively, were prepared by a photolithography process, chemical vapor adsorption method, and surface-initiated polymerization. A droplet of water containing dye was placed on the line-patterned surface. In front of the contact line, a water film with a nanometer-scale thickness, referred to as a precursor film, elongated along the polymer brush line with time. The elongation velocity at the first stage increased as the brush line width increased. On the other hand, at the second stage after the macroscopic contact line stopped moving, the precursor film continued to elongate in proportion to the 0.6 power of time, independent of the brush thickness, line width, and droplet volume.
Collapse
|
13
|
Zhao B, Yuan G, Chu X, Yang J, Zhao J. Response of a Permanently Charged Polyelectrolyte Brush to External Ions: The Aspects of Structure and Dynamics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:6757-6765. [PMID: 29781623 DOI: 10.1021/acs.langmuir.8b01195] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Structure and dynamics inside permanently charged polyelectrolyte brushes, sodium polystyrene sulfonate brushes, during their response to the introduction of external ions (NaCl) are investigated by neutron reflectivity and dielectric spectroscopy. Neutron reflectivity measurements show that the segmental density of the inner part of the brushes decreases and that of the outer part increases when the salt level is tuned from the salt-free condition to a moderate level (<10-2 M)-the brushes swell further compared with the salt-free condition. This is attributed to the breakup of the multiplets formed by dipole-dipole pairs, and by this process, the previously constrained chain segments by the multiplets are released. Dielectric spectroscopy discovers a giant dipole by the charge separation of the adsorbed counterions and the PSS- chains, induced by electric field. The dynamics of the induced giant dipole is accelerated with the increase of external salt, as a result of the charge regularization by elevated salt level. At high-enough salt level, the screening effect reduces the electrostatic repulsion between the neighboring chains and makes the brushes shrink.
Collapse
Affiliation(s)
- Bintao Zhao
- Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China
- University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Guangcui Yuan
- Center for Neutron Research , National Institute of Standards and Technology , Gaithersburg , Maryland 20899 , United States
| | - Xiao Chu
- Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China
| | - Jingfa Yang
- Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China
| | - Jiang Zhao
- Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China
| |
Collapse
|
14
|
Han L, Yan B, Zhang L, Wu M, Wang J, Huang J, Deng Y, Zeng H. Tuning protein adsorption on charged polyelectrolyte brushes via salinity adjustment. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.12.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
15
|
Higaki Y, Inutsuka Y, Sakamaki T, Terayama Y, Takenaka A, Higaki K, Yamada NL, Moriwaki T, Ikemoto Y, Takahara A. Effect of Charged Group Spacer Length on Hydration State in Zwitterionic Poly(sulfobetaine) Brushes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2017; 33:8404-8412. [PMID: 28737401 DOI: 10.1021/acs.langmuir.7b01935] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Effect of alkyl chain spacer length between the charged groups (CSL) in zwitterionic poly(sulfobetaine) (PSB) brushes on the hydration state was investigated. PSB brushes with ethyl (PMAES), propyl (PMAPS), or butyl (PMABS) CSL were prepared by surface-initiated atom transfer radical polymerization on silicon wafers. Hydration states of the PSB brushes in aqueous solutions and/or humid vapor were investigated by contact angle measurement, infrared spectroscopy, AFM observation, and neutron reflectivity. The PSB brushes are swollen in humid air and deionized water due to the hydration of the charged groups leading to the reduction of hydrated PSB brushes/water interfacial free energy. The hydrated PSB brushes exhibit clear interface with low interfacial roughness due to networking of the PSB brush chains through association of the SBs. The hydrated PSB brushes produce diffusive swollen layer in the presence of NaCl because of the charge screening followed by SB dissociation by the bound ions. The ionic strength sensitivity in the hydration got more significant with increasing the CSL in SBs because of the augmentation in partial charge by charged group separation.
Collapse
Affiliation(s)
- Yuji Higaki
- Institute for Materials Chemistry and Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
- Graduate School of Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
- Japan Science and Technology Agency (JST), ERATO, Takahara Soft Interfaces Project, CE80, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yoshihiro Inutsuka
- Graduate School of Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Tatsunori Sakamaki
- Graduate School of Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Yuki Terayama
- Graduate School of Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Ai Takenaka
- Japan Science and Technology Agency (JST), ERATO, Takahara Soft Interfaces Project, CE80, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Keiko Higaki
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| | - Norifumi L Yamada
- Neutron Science Laboratory, High Energy Accelerator Research Organization , Ibaraki 319-1106, Japan
| | - Taro Moriwaki
- Japan Synchrotron Radiation Research Institute/SPring-8 , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Yuka Ikemoto
- Japan Synchrotron Radiation Research Institute/SPring-8 , 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198, Japan
| | - Atsushi Takahara
- Institute for Materials Chemistry and Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
- International Institute for Carbon-Neutral Energy Research (WPI-I2CNER), Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
- Graduate School of Engineering, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
- Japan Science and Technology Agency (JST), ERATO, Takahara Soft Interfaces Project, CE80, Kyushu University , 744 Motooka, Nishi-ku, Fukuoka 819-0395, Japan
| |
Collapse
|
16
|
|