1
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G Lopez C, Matsumoto A, Shen AQ. Dilute polyelectrolyte solutions: recent progress and open questions. SOFT MATTER 2024; 20:2635-2687. [PMID: 38427030 DOI: 10.1039/d3sm00468f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2024]
Abstract
Polyelectrolytes are a class of polymers possessing ionic groups on their repeating units. Since counterions can dissociate from the polymer backbone, polyelectrolyte chains are strongly influenced by electrostatic interactions. As a result, the physical properties of polyelectrolyte solutions are significantly different from those of electrically neutral polymers. The aim of this article is to highlight key results and some outstanding questions in the polyelectrolyte research from recent literature. We focus on the influence of electrostatics on conformational and hydrodynamic properties of polyelectrolyte chains. A compilation of experimental results from the literature reveals significant disparities with theoretical predictions. We also discuss a new class of polyelectrolytes called poly(ionic liquid)s that exhibit unique physical properties in comparison to ordinary polyelectrolytes. We conclude this review by listing some key research challenges in order to fully understand the conformation and dynamics of polyelectrolytes in solutions.
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Affiliation(s)
- Carlos G Lopez
- Institute of Physical Chemistry, RWTH Aachen University, Aachen, 52056, Germany
| | - Atsushi Matsumoto
- Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, University of Fukui, 3-9-1 Bunkyo, Fukui City, Fukui 910-8507, Japan.
| | - Amy Q Shen
- Micro/Bio/Nanofluidics Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan.
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2
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Kleemann K, Bolduan P, Battagliarin G, Christl I, McNeill K, Sander M. Molecular Structure and Conformation of Biodegradable Water-Soluble Polymers Control Adsorption and Transport in Model Soil Mineral Systems. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1274-1286. [PMID: 38164921 PMCID: PMC10795197 DOI: 10.1021/acs.est.3c05770] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 01/03/2024]
Abstract
Water-soluble polymers (WSPs) are used in diverse applications, including agricultural formulations, that can result in the release of WSPs to soils. WSP biodegradability in soils is desirable to prevent long-term accumulation and potential associated adverse effects. In this work, we assessed adsorption of five candidate biodegradable WSPs with varying chemistry, charge, and polarity characteristics (i.e., dextran, diethylaminoethyl dextran, carboxymethyl dextran, polyethylene glycol monomethyl ether, and poly-l-lysine) and of one nonbiodegradable WSP (poly(acrylic acid)) to sand and iron oxide-coated sand particles that represent important soil minerals. Combined adsorption studies using solution-depletion measurements, direct surface adsorption techniques, and column transport experiments over varying solution pH and ionic strengths revealed electrostatics dominating interactions of charged WSPs with the sorbents as well as WSP conformations and packing densities in the adsorbed states. Hydrogen bonding controls adsorption of noncharged WSPs. Under transport in columns, WSP adsorption exhibited fast and slow kinetic adsorption regimes with time scales of minutes to hours. Slow adsorption kinetics in soil may lead to enhanced transport but also shorter lifetimes of biodegradable WSPs, assuming more rapid biodegradation when dissolved than adsorbed. This work establishes a basis for understanding the coupled adsorption and biodegradation dynamics of biodegradable WSPs in agricultural soils.
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Affiliation(s)
- Kevin Kleemann
- Institute
of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland
| | - Patrick Bolduan
- BASF
SE, Materials and Formulation Research, Carl-Bosch-Strasse 38, 67056 Ludwigshafen, Germany
| | - Glauco Battagliarin
- BASF
SE, Materials and Formulation Research, Carl-Bosch-Strasse 38, 67056 Ludwigshafen, Germany
| | - Iso Christl
- Institute
of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland
| | - Kristopher McNeill
- Institute
of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland
| | - Michael Sander
- Institute
of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland
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3
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Gopalakrishnan A, Bouby M, Schäfer AI. Membrane-organic solute interactions in asymmetric flow field flow fractionation: Interplay of hydrodynamic and electrostatic forces. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 855:158891. [PMID: 36411600 DOI: 10.1016/j.scitotenv.2022.158891] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2022] [Revised: 09/16/2022] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
The structure and size characterization of organic matter (OM) using flow field-flow fractionation (FFFF) is interesting due to the numerous interactions of OM in aquatic systems and water treatment processes. The estimation of hydrodynamic and electrostatic forces involved in the fractionation of OM over different molecular weight cut-off (MWCO) membranes is vital for a better understanding of the FFFF process. This work aims to understand the membrane-OM interactive forces with respect to membrane MWCO, solute molecular weight, flow rates, solution pH and ionic strength. Polystyrene sulfonate sodium salt (PSS) of molecular weights 10, 30 and 65 kDa were used as model organic solutes for fractionation over ultrafiltration (UF) membranes of MWCO 1-30 kDa. Maximum fractionation of PSS was achieved by using a tight membrane of 1 kDa MWCO at the conditions of high permeate flow rate (1.5-2.0 mL·min-1), low concentrate flow rate (0.2-0.3 mL·min-1) and low ionic strength (10 mM). The better fractionation corresponds to high permeate drag force and low concentrate drag force. A low membrane-solute DLVO interaction is favourable for the retention of a small solute. This study illustrated that FFFF characteristics can be analyzed based on membrane-solute interactive forces controlled by selected flow, size and charge parameters.
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Affiliation(s)
- Akhil Gopalakrishnan
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Muriel Bouby
- Institute for Nuclear Waste Disposal (INE), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany
| | - Andrea I Schäfer
- Institute for Advanced Membrane Technology (IAMT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
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4
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Liu T, Wang P, Tian J, Guo J, Zhu W, Seidi F, Jin Y, Xiao H, Song J. Enzymatic saccharification promotion for bioenergy poplar under green liquor pretreatment by fully sulfonated polystyrene: Effect of molecular weight. BIORESOURCE TECHNOLOGY 2022; 363:127904. [PMID: 36108943 DOI: 10.1016/j.biortech.2022.127904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/31/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
Water-soluble lignin and lignin derivatives are cited to promote the enzymatic saccharification of lignocellulose. Herein, a series of fully sulfonated polystyrene sulfonates (FSPSSs) with various molecular weights (MW) were synthesized through free radical polymerization (FRP) and atom transfer radical polymerization (ATRP) to serve as lignin analogues to boost the enzymatic saccharification of bioenergy poplar under green liquor pretreatment. The FRP-made polymers with MW 944.5 × 103 to 123.6 × 103 g/mol increased the enzymatic hydrolysis digestibility (SED) by 13 % to 18.8 %. On contrary, the ATRP-made polymers with lower MW (3.8 × 103-12.2 × 103 g/mol) showed a weak effect with<8 % improvement in SED. This can be explained the adsorption capacity and the conformation of cellulase-FSPSS complexes, which respond to the reducing nonproductive adsorption correlated to their MWs, due to the strong dependence of molecular conformation on the chain length of strong polyelectrolytes.
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Affiliation(s)
- Tian Liu
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China
| | - Peipei Wang
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China
| | - Jing Tian
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China
| | - Jiaqi Guo
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China
| | - Wenyuan Zhu
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China
| | - Fazard Seidi
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China
| | - Yongcan Jin
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China
| | - Huining Xiao
- Department of Chemical Engineering, University of New Brunswick, Fredericton, NB E3B 5A3, Canada
| | - Junlong Song
- Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources and International Innovation Center for Forest Chemicals and Materials, Nanjing Forestry University, Nanjing 210037, China.
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5
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Zhou C, Ji C, Nie Y, Yang J, Zhao J. Poly(ethylene oxide) Is Positively Charged in Aqueous Solutions. Gels 2022; 8:gels8040213. [PMID: 35448114 PMCID: PMC9029200 DOI: 10.3390/gels8040213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Revised: 03/23/2022] [Accepted: 03/29/2022] [Indexed: 11/16/2022] Open
Abstract
There have been controversies about the binding of cations to poly(ethylene oxide) (PEO) chains in aqueous solutions. In the current study, single molecular evidence of charging PEO chains by cation binding in aqueous solutions is provided. From the adoption of the photon-counting histogram method, it is discovered that the local pH value at the vicinity of the PEO chain is higher than the bulk solution, showing that the PEO chain is positively charged. Such a situation exists with and without the presence of salt (NaCl) in the solution, presumably due to the binding of cations, such as hydronium and sodium ions. Single molecular electrophoresis experiments using fluorescence correlation spectroscopy demonstrate that the PEO chains are weakly charged with a charging extent of ~5%. In comparison to the salt-free condition, the addition of external salt (NaCl) at moderate concentrations further charges the chain. The charging causes the PEO chains to expand and a further increase in the salt concentration causes the chain to shrink, exhibiting a polyelectrolyte-like behavior, demonstrated by the hydrodynamic radii of a single PEO chain. The effect of ion identity is discovered with alkali cations, with the order of the charging capacity of Li+ < Na+ < Cs+ < K+.
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Affiliation(s)
- Chao Zhou
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chunda Ji
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuchen Nie
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfa Yang
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiang Zhao
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China; (C.Z.); (C.J.); (Y.N.); (J.Y.)
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
- Correspondence:
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Zheng K, Chen K, Ren W, Yang J, Zhao J. Shear-Induced Counterion Release of a Polyelectrolyte. Macromolecules 2022. [DOI: 10.1021/acs.macromol.1c02275] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kaikai Zheng
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kuo Chen
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
| | - Weibin Ren
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfa Yang
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiang Zhao
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
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7
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Ou Z, Liang B, Liang Z, Tan F, Dong X, Gong L, Zhao P, Wang H, Zou Y, Xia Y, Chen X, Liu W, Qi H, Kaiser U, Zheng Z. Oriented Growth of Thin Films of Covalent Organic Frameworks with Large Single-Crystalline Domains on the Water Surface. J Am Chem Soc 2022; 144:3233-3241. [PMID: 35147035 DOI: 10.1021/jacs.1c13195] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
It has been a longstanding challenge to rationally synthesize thin films of organic two-dimensional (2D) crystals with large single-crystalline domains. Here, we present a general strategy for the creation of 2D crystals of covalent organic frameworks (COFs) on the water surface, assisted by a charged polymer. The morphology of the preorganized monomers underneath the charged polymer on the water surface and their diffusion were crucial for the formation of the organic 2D crystals. Thin films of 2D COFs with an average single-crystalline domain size of around 3.57 ± 2.57 μm2 have been achieved, and their lattice structure, molecular structure, and grain boundaries were identified with a resolution down to 3 Å. The swing of chain segments and lattice distortion were revealed as key factors in compensating for the misorientation between adjacent grains and facilitating error corrections at the grain boundaries, giving rise to larger single-crystalline domains. The generality of the synthesis method was further proved with three additional 2D COFs. The oriented single-crystalline domains and clear grain boundaries render the films as model materials to study the dependence of the vertical conductivity of organic 2D crystals on domain sizes and chemical structures, and significant grain boundary effects were illustrated. This study presents a breakthrough in the controlled synthesis of organic 2D crystals with structural control at the molecular level. We envisage that this work will inspire further investigation into the microstructure-intrinsic property correlation of 2D COFs and boost their application in electronics.
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Affiliation(s)
- Zhaowei Ou
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Baokun Liang
- Central Facility of Materials Science Electron Microscopy, Universität Ulm, 89081 Ulm, Germany
| | - Zihao Liang
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Fanglin Tan
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Xin Dong
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Li Gong
- Instrumental Analysis and Research Center, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Pei Zhao
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Honglei Wang
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Yuhai Zou
- Departments of Cardiology, General Hospital of Southern Theatre Command of PLA, 510010 Guangzhou, China
| | - Yuanjun Xia
- Guangdong Key Lab of Orthopedic Technology and Implant Materials, Department of Orthopaedics, General Hospital of Southern Theater Command of PLA, The First School of Clinical Medicine of Southern Medical University, 510010 Guangzhou, China
| | - Xudong Chen
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Wei Liu
- Key Laboratory of Low-Carbon Chemistry & Energy Conservation of Guangdong Province, Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Materials Science and Engineering, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
| | - Haoyuan Qi
- Central Facility of Materials Science Electron Microscopy, Universität Ulm, 89081 Ulm, Germany.,Center for Advancing Electronics Dresden (cfaed) and Faculty of Chemistry and Food Chemistry, Technical University of Dresden, 01069 Dresden, Germany
| | - Ute Kaiser
- Central Facility of Materials Science Electron Microscopy, Universität Ulm, 89081 Ulm, Germany
| | - Zhikun Zheng
- Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education, School of Chemistry, and State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, 510275 Guangzhou, Guangdong, China
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Liu T, Wang P, Tian J, Guo J, Zhu W, Jin Y, Xiao H, Song J. Polystyrene sulfonate is effective for enhancing biomass enzymatic saccharification under green liquor pretreatment in bioenergy poplar. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:10. [PMID: 35418140 PMCID: PMC8783513 DOI: 10.1186/s13068-022-02108-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 01/08/2022] [Indexed: 05/31/2023]
Abstract
BACKGROUND Water-soluble lignin (particularly lignosulfonate, LS) has been well documented for its significance on enzymatic saccharification of lignocellulose, though the promotion mechanism has not been fully understood. Much attention has been paid to natural lignin or its derivatives. The disadvantage of using natural lignin-based polymers as promoting agents lies in the difficulty in tailor-incorporating functional groups due to their complex 3D structures. To further improve our understanding on the promotion mechanism of water-soluble lignin in the bioconversion of lignocellulose and to pursue better alternatives with different skeleton structures other than natural lignin, herein we reported a synthetic soluble linear aromatic polymer, sodium polystyrene sulfonate (PSS), to mimic LS for enhancing the efficiency of enzymatic saccharification. RESULTS The role of PSS in enzymatic saccharification of pure cellulose and green liquor-pretreated poplar (GL-P) was explored by analyzing substrate enzymatic digestibility (SED) under different addition dosages and various pH media, along with LS for comparison. At the cellulase loading of 13.3 FPU/g-glucan, the glucose yield of GL-P increased from 53% for the control to 81.5% with PSS addition of 0.1 g/g-substrate. It outperformed LS with the addition of 0.2 g/g-substrate by 6.3%. In the pH range from 4.5 to 6, PSS showed a positive effect on lignocellulose saccharification with the optimum pH at 4.8, where the most pronounced SED of GL-P was achieved. The underlying mechanism was unveiled by measuring zeta potential and using Quartz Crystal Microbalance (QCM) and Multi-parametric Surface Plasmon Resonance (MP-SPR). The results confirmed that the complexes of cellulase and PSS were conjugated and the negatively supercharged complexes reduced non-productive binding effectively along with the improved saccharification efficiency. The thickness of PSS required to block the binding sites of cellulase film was less than half of that of LS, and the PSS adlayer on cellulase film is also more hydrated and with a much lower shear modulus than LS adlayer. CONCLUSIONS PSS as LS analogue is effective for enhancing the biomass enzymatic saccharification of GL-pretreated poplar. PSS exhibited a severer inhibition on the enzymatic saccharification of pure cellulose, while a more positive effect on bioconversion of lignocellulose (GL-P) than LS. In addition, a much lower dosage is required by PSS. The dynamic enzymatic hydrolysis indicated PSS could prolong the processive activity of cellulase. The valid data stemmed from QCM and SPR expressed that PSS bound to cellulases and the as-formed complexes reduced the non-productive adsorption of cellulase onto substrate lignin more efficiently than LS due to its flexible skeleton and highly hydrated structure. Therefore, PSS is a promising alternative promoting agent for lignocellulose saccharification. From another perspective, the synthetic lignin mimics with controllable structures enable us to reach an in-depth understanding of the promotion mechanism of soluble lignins on enzymatic saccharification.
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Affiliation(s)
- Tian Liu
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
| | - Peipei Wang
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
| | - Jing Tian
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
| | - Jiaqi Guo
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China.
| | - Wenyuan Zhu
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
| | - Yongcan Jin
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China
| | - Huining Xiao
- Department of Chemical Engineering, University of New Brunswick, Fredericton, NB, E3B 5A3, Canada
| | - Junlong Song
- International Innovation Center for Forest Chemicals and Materials and Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing, 210037, China.
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9
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Lopez CG, Linders J, Mayer C, Richtering W. Diffusion and Viscosity of Unentangled Polyelectrolytes. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c01169] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- Carlos G. Lopez
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
| | - Jürgen Linders
- Physical Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, 45117 Essen, Germany
| | - Christian Mayer
- Physical Chemistry and Center for Nanointegration Duisburg-Essen (CeNIDE), University of Duisburg-Essen, 45117 Essen, Germany
| | - Walter Richtering
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany
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10
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Affiliation(s)
- Yu Shi
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
| | - Hao Peng
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfa Yang
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiang Zhao
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- The University of Chinese Academy of Sciences, Beijing 100049, China
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11
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Zhao J. Studying the physics of charged macromolecules by single molecule fluorescence spectroscopy. J Chem Phys 2020; 153:170903. [PMID: 33167636 DOI: 10.1063/5.0024324] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
It is well documented that conventional methods such as dynamic light scattering have encountered difficulties in characterizing charged macromolecules and, therefore, it is desirable that new methods and techniques are introduced. With the ultra-high sensitivity, single molecule fluorescence spectroscopy has successfully lowered the detection limit considerably and enabled measurement under extreme dilution conditions-around the concentration of 10-9M-at which the effect of inter-chain electrostatic repulsion is suppressed. Furthermore, the excellent spatial and temporal resolution as well as the capacity of molecular recognition of these methods help in obtaining rich information of charged macromolecules. This paper summarizes the applications of single molecule fluorescence spectroscopy, especially fluorescence correlation spectroscopy and photon counting histogram, in the studies on charged macromolecules in aqueous solutions and plenty of new information has been revealed on the molecular conformation, counterion distribution, and a few important governing factors. The powerfulness and effectiveness of single molecule fluorescence spectroscopy make it promising in the investigations of charged macromolecules.
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Affiliation(s)
- Jiang Zhao
- Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China and The University of Chinese Academy of Sciences, Beijing 100049, China
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12
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Lopez CG, Horkay F, Mussel M, Jones RL, Richtering W. Screening lengths and osmotic compressibility of flexible polyelectrolytes in excess salt solutions. SOFT MATTER 2020; 16:7289-7298. [PMID: 32667374 PMCID: PMC8281568 DOI: 10.1039/d0sm00464b] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We report results of small angle neutron scattering measurements made on sodium polystyrene sulfonate in aqueous salt solutions. The correlation length (ξ) and osmotic compressibility are measured as a function of polymer (c) and added salt (cS) concentrations, and the results are compared with scaling predictions and the random-phase approximation (RPA). In Dobrynin et al.'s scaling model the osmotic pressure consists of a counter-ion contribution and a polymer contribution. The polymer contribution is found to be two orders of magnitude smaller than expected from the scaling model, in agreement with earlier observations made on neutral polymers in good solvent condition. RPA allows the determination of single-chain dimensions in semidilute solutions at high polymer and added salt concentrations, but fails for cS≤ 2 M. The χ parameter can be modelled as the sum of an intrinsic contribution (χ0) and an electrostatic term: χ∼χ0 + K'/√cS, where χ0 > 0.5 is consistent with the hydrophobic nature of the backbone of NaPSS. The dependence of χelec∼ 1/√cS disagrees with the random-phase approximation (χelec∼ 1/cs), but agrees with the light scattering results in dilute solution and Dobrynin et al.'s scaling treatment of electrostatic excluded volume.
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Affiliation(s)
- Carlos G Lopez
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52056 Aachen, Germany.
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Penfold J, Thomas RK. Counterion Condensation, the Gibbs Equation, and Surfactant Binding: An Integrated Description of the Behavior of Polyelectrolytes and Their Mixtures with Surfactants at the Air-Water Interface. J Phys Chem B 2020; 124:6074-6094. [PMID: 32608983 DOI: 10.1021/acs.jpcb.0c02988] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
By applying the Gibbs equation to the bulk binding isotherms and surface composition of the air-water (A-W) interface in polyelectrolyte-surfactant (PE-S) systems, we show that their surface behavior can be explained semiquantitatively in terms of four concentration regions, which we label as A, B, C, and D. In the lowest-concentration range A, there are no bound PE-S complexes in the bulk but there may be adsorption of PE-S complexes at the surface. When significant adsorption occurs in this region, the surface tension (ST) drops with increasing concentration like a simple surfactant solution. Region B extends from the onset of bulk PE-S binding to the end of cooperative binding, in which the slow variation of surfactant activity with cooperative binding means that the ST changes relatively little, although adsorption may be significant. This leads to an approximate plateau, which may be at high or low ST. Region C starts where the binding in the bulk complex loses its cooperativity leading to a rapid change of surfactant activity with the total concentration. This, combined with significant adsorption, often leads to a sharp drop in ST. Region D is where precipitation and redissolution of the bulk PE-S complex occur. ST peaks may arise in region D because of loss of the solution complex that matches the value of the preferred surface stoichiometry, which seems to have a well-defined value for each system. The analysis is applied to the experimental systems, sodium polystyrene sulfonate-alkyltrimethylammonium bromides and poly(diallyldimethyl chloride)-sodium alkyl sulfates, with and without the added electrolyte, and includes data from bulk binding isotherms, phase diagrams, aggregation behavior, and direct measurements of the surface excess and stoichiometry of the surface. The successful fits of the Gibbs equation to the data confirm that the surfaces in these systems are largely equilibrated.
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Affiliation(s)
- Jeffrey Penfold
- STFC, Rutherford-Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0RA, U.K
| | - Robert K Thomas
- Physical and Theoretical Chemistry Laboratory, South Parks Road, Oxford OX1 3QZ, U.K
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Lopez CG, Richtering W. Viscosity of Semidilute and Concentrated Nonentangled Flexible Polyelectrolytes in Salt-Free Solution. J Phys Chem B 2019; 123:5626-5634. [PMID: 31124680 DOI: 10.1021/acs.jpcb.9b03044] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
We report viscosity data of nonentangled sodium polystyrene sulfonate (NaPSS) in salt-free aqueous solution as a function of polymer concentration ( c) and degree of polymerization ( N). Different empirical equations are examined and found not to describe the semidilute solution viscosity over a wide concentration range and/or to yield values of [η] that do not match dilute solution measurements. Deviations from the scaling prediction of ηsp ∝ c1/2 (Fuoss' law) are observed at high concentrations. Specifically, we find ηsp ≈ N1.26 c1/2 e1.4 c in the semidilute regime, which agrees with the scaling prediction only for c ≲ 0.02 M. The viscosity data presented in this study and in earlier reports show a high degree of consistency. A comparison with diffusion measurements for NaPSS in salt-free solution by Oostwal and co-workers suggests that the disagreement between the scaling theory and experiments does not arise solely from the concentration dependence of the monomeric friction coefficient.
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Affiliation(s)
- Carlos G Lopez
- Institute of Physical Chemistry , RWTH Aachen University , Landoltweg 2 , 52056 Aachen , Germany
| | - Walter Richtering
- Institute of Physical Chemistry , RWTH Aachen University , Landoltweg 2 , 52056 Aachen , Germany
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Chen K, Zheng K, Xu G, Yang J, Zhao J. Diffusive Motion of Single Polyelectrolyte Molecules under Electrostatic Repulsion. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Kuo Chen
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaikai Zheng
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guofeng Xu
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingfa Yang
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiang Zhao
- Beijing National Research Center for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
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Jia D, Muthukumar M. Effect of Salt on the Ordinary-Extraordinary Transition in Solutions of Charged Macromolecules. J Am Chem Soc 2019; 141:5886-5896. [PMID: 30896938 DOI: 10.1021/jacs.9b00562] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Using dynamic light scattering technique, we address the role of added salt at higher concentrations on the "ordinary-extraordinary" transition in solutions of charged macromolecules. The "ordinary" behavior has previously been associated with a "fast" diffusion coefficient which is independent of salt concentration Cs and polymer concentration Cp if the ratio Cp/ Cs is above a threshold value. The "extraordinary" transition is associated with formation of aggregates, with a "slow" diffusion coefficient, formed from similarly charged macromolecules. By investigating aqueous solutions of sodium poly(styrenesulfonate) and sodium chloride with variations in Cp, Cs, and polymer molecular weight, Mw, we report the emergence of a new diffusive "fast" relaxation mode at higher values of Cp, Cs, and Mw, in addition to the previously known "fast" and "slow" relaxation modes. Furthermore, we find that Mw plays a crucial role on the collective dynamics of polyelectrolyte solutions with salt, instead of just the Cp/ Cs ratio as previously postulated. As Mw is progressively decreased, the salty solution exhibits dynamical transitions from three modes to two modes and then to one mode of relaxation. The emergence of the new fast mode and the dynamical transitions are in marked departure from the general premise of the ordinary-extraordinary transition developed over several decades. In an effort to rationalize our experimental findings we present a theory for the collective dynamics of polyelectrolyte solutions with salt by addressing the coupling between the relaxations of polyelectrolyte chains, counterions from the polymer and added salt, and co-ions from the salt. The predictions are in qualitative agreement with experimental findings. The present combined work of experiments and theory forms the basis for accurately characterizing dynamics of charged macromolecules in salty solutions, which are ubiquitous in biological systems and polyelectrolyte-based technologies.
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Affiliation(s)
- Di Jia
- Department of Polymer Science and Engineering , University of Massachusetts , Amherst , Massachusetts 01003 , United States
| | - Murugappan Muthukumar
- Department of Polymer Science and Engineering , University of Massachusetts , Amherst , Massachusetts 01003 , United States
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