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Mantha S, Glisman A, Yu D, Wasserman EP, Backer S, Wang ZG. Adsorption Isotherm and Mechanism of Ca 2+ Binding to Polyelectrolyte. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:6212-6219. [PMID: 38497336 DOI: 10.1021/acs.langmuir.3c03640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Polyelectrolytes, such as poly(acrylic acid) (PAA), can effectively mitigate CaCO3 scale formation. Despite their success as antiscalants, the underlying mechanism of binding of Ca2+ to polyelectrolyte chains remains unresolved. Through all-atom molecular dynamics simulations, we constructed an adsorption isotherm of Ca2+ binding to sodium polyacrylate (NaPAA) and investigated the associated binding mechanism. We find that the number of calcium ions adsorbed [Ca2+]ads to the polymer saturates at moderately high concentrations of free calcium ions [Ca2+]aq in the solution. This saturation value is intricately connected with the binding modes accessible to Ca2+ ions when they bind to the polyelectrolyte chain. We identify two dominant binding modes: the first involves binding to at most two carboxylate oxygens on a polyacrylate chain, and the second, termed the high binding mode, involves binding to four or more carboxylate oxygens. As the concentration of free calcium ions [Ca2+]aq increases from low to moderate levels, the polyelectrolyte chain undergoes a conformational transition from an extended coil to a hairpin-like structure, enhancing the accessibility to the high binding mode. At moderate concentrations of [Ca2+]aq, the high binding mode accounts for at least one-third of all binding events. The chain's conformational change and its consequent access to the high binding mode are found to increase the overall Ca2+ ion binding capacity of the polyelectrolyte chain.
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Affiliation(s)
- Sriteja Mantha
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Alec Glisman
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Decai Yu
- Core R&D, The Dow Chemical Company, 633 Washington St., Midland, Michigan 48674, United States
| | - Eric P Wasserman
- Consumer Solutions R&D, The Dow Chemical Company, 400 Arcola Road, Collegeville, Pennsylvania 19426, United States
| | - Scott Backer
- Consumer Solutions R&D, The Dow Chemical Company, 400 Arcola Road, Collegeville, Pennsylvania 19426, United States
| | - Zhen-Gang Wang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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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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Kurapati R, Natarajan U. Complex role of chemical nature and tacticity in the adsorption free energy of carboxylic acid polymers at the oil-water interface: molecular dynamics simulations. Phys Chem Chem Phys 2023; 25:27783-27797. [PMID: 37814803 DOI: 10.1039/d3cp02754f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/11/2023]
Abstract
Scientific understanding of the molecular structure and adsorption of polymers at oil-water liquid interfaces is very limited. In this study the adsorption free energy at the oil (CCl4)-water interface was estimated using umbrella sampling molecular dynamics simulations for six carboxylate type vinyl polymers differing in hydrophobic nature and tacticity: isotactic and syndiotactic poly(acrylic acid) (i-PAA, s-PAA), isotactic and syndiotactic poly(methacrylic acid) (i-PMA, s-PMA), and atactic and syndiotactic poly(ethylacrylic acid) (a-PEA, s-PEA). ΔGads values are in the order i-PMA < a-PEA < s-PEA < s-PAA < i-PAA < s-PMA. The results show the significant and complex influence of the chemical nature as well as tacticity of the polymer on its adsorption free energy as related to hydrogen bonding and orientation of bonds with respect to oil and water phases. The influence of tacticity is found to be the highest for PMA, which is interpreted to occur due to the balance between interactions among side groups and those occurring between side groups and solvent. Interactions between side-groups are crucial for determining the conformation of PAA (most hydrophilic) and the solvation of the side-group in water is crucial for determining the conformation of PEA (most hydrophobic). The adsorption of PMA represents the transition between these two dominating effects. The molecular contributions to the enthalpy of adsorption indicate that adsorption is favored mainly through two interactions: polymer-CCl4 and water-water.
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Affiliation(s)
- Raviteja Kurapati
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai, 600036, India.
| | - Upendra Natarajan
- Macromolecular Modeling and Simulation Laboratory, Department of Chemical Engineering, Indian Institute of Technology (IIT) Madras, Chennai, 600036, India.
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Lew JH, Matar OK, Müller EA, Luckham PF, Sousa Santos A, Myo Thant MM. Atomic Force Microscopy of Hydrolysed Polyacrylamide Adsorption onto Calcium Carbonate. Polymers (Basel) 2023; 15:4037. [PMID: 37896286 PMCID: PMC10609783 DOI: 10.3390/polym15204037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/28/2023] [Accepted: 10/05/2023] [Indexed: 10/29/2023] Open
Abstract
In this work, the interaction of hydrolysed polyacrylamide (HPAM) of two molecular weights (F3330, 11-13 MDa; F3530, 15-17 MDa) with calcium carbonate (CaCO3) was studied via atomic force microscopy (AFM). In the absence of polymers at 1.7 mM and 1 M NaCl, good agreement with DLVO theory was observed. At 1.7 mM NaCl, repulsive interaction during approach at approximately 20 nm and attractive adhesion of approximately 400 pN during retraction was measured, whilst, at 1 M NaCl, no repulsion during approach was found. Still, a significantly larger adhesion of approximately 1400 pN during retraction was observed. In the presence of polymers, results indicated that F3330 displayed higher average adhesion (450-625 pN) and interaction energy (43-145 aJ) with CaCO3 than F3530's average adhesion (85-88 pN) and interaction energy (8.4-11 aJ). On the other hand, F3530 exerted a longer steric repulsion distance (70-100 nm) than F3330 (30-70 nm). This was likely due to the lower molecular weight. F3330 adopted a flatter configuration on the calcite surface, creating more anchor points with the surface in the form of train segments. The adhesion and interaction energy of both HPAM with CaCO3 can be decreased by increasing the salt concentration. At 3% NaCl, the average adhesion and interaction energy of F3330 was 72-120 pN and 5.6-17 aJ, respectively, while the average adhesion and interaction energy of F3530 was 11.4-48 pN and 0.3-2.98 aJ, respectively. The reduction of adhesion and interaction energy was likely due to the screening of the COO- charged group of HPAM by salt cations, leading to a reduction of electrostatic attraction between the negatively charged HPAM and the positively charged CaCO3.
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Affiliation(s)
- Jin Hau Lew
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (O.K.M.); (E.A.M.); (P.F.L.); (A.S.S.)
| | - Omar K. Matar
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (O.K.M.); (E.A.M.); (P.F.L.); (A.S.S.)
| | - Erich A. Müller
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (O.K.M.); (E.A.M.); (P.F.L.); (A.S.S.)
| | - Paul F. Luckham
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (O.K.M.); (E.A.M.); (P.F.L.); (A.S.S.)
| | - Adrielle Sousa Santos
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (O.K.M.); (E.A.M.); (P.F.L.); (A.S.S.)
| | - Maung Maung Myo Thant
- PETRONAS Research Sdn. Bhd., Lot 3288 & 3289, Off Jalan Ayer Itam, Kawasan Institusi Bangi, Kajang 43000, Selangor, Malaysia;
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Durkin TJ, Barua B, Holmstrom JJ, Karanikola V, Savagatrup S. Functionalized Amphiphilic Block Copolymers and Complex Emulsions for Selective Sensing of Dissolved Metals at Liquid-Liquid Interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:12845-12854. [PMID: 37625160 DOI: 10.1021/acs.langmuir.3c01761] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/27/2023]
Abstract
Increasing contamination in potable water supplies necessitates the development of sensing methods that provide the speed and selectivity necessary for safety. One promising method relies on recognition and detection at the liquid-liquid interface of dynamic complex emulsions. These all-liquid materials transduce changes in interfacial tensions into optical signals via the coupling of their chemical, physical, and optical properties. Thus, to introduce selectivity, it is necessary to modify the liquid-liquid interface with an interfacially stable and selective recognition unit. To this end, we report the synthesis and characterization of amphiphilic block copolymers modified with metal chelators to selectively measure the concentrations of dissolved metal ions. We find that significant reduction in interfacial tensions arises upon quantitative addition of metal ions with high affinity toward functionalized chelators. Furthermore, measurements from UV-vis spectroscopy reveal that complexation of the block copolymers with metal ions leads to an increase in surface excess and surfactant effectiveness. We also demonstrate selective detection of iron(III) cations (Fe3+) on the μM levels even through interference from other mono-, di-, or trivalent cations in complex matrices of synthetic groundwater. Our results provide a unique platform that couples selective recognition and modulation of interfacial behaviors and demonstrates a step forward in the development of the multiplexed sensing device needed to deconvolute the complicated array of contaminants that comprise real-world environmental samples.
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Affiliation(s)
- Tyler J Durkin
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, United States
| | - Baishali Barua
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, United States
| | - Jamie J Holmstrom
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, United States
| | - Vasiliki Karanikola
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, United States
| | - Suchol Savagatrup
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, United States
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Hue KY, Lew JH, Myo Thant MM, Matar OK, Luckham PF, Müller EA. Molecular Dynamics Simulation of Polyacrylamide Adsorption on Calcite. Molecules 2023; 28:6367. [PMID: 37687196 PMCID: PMC10563068 DOI: 10.3390/molecules28176367] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 08/21/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023] Open
Abstract
In poorly consolidated carbonate rock reservoirs, solids production risk, which can lead to increased environmental waste, can be mitigated by injecting formation-strengthening chemicals. Classical atomistic molecular dynamics (MD) simulation is employed to model the interaction of polyacrylamide-based polymer additives with a calcite structure, which is the main component of carbonate formations. Amongst the possible calcite crystal planes employed as surrogates of reservoir rocks, the (1 0 4) plane is shown to be the most suitable surrogate for assessing the interactions with chemicals due to its stability and more realistic representation of carbonate structure. The molecular conformation and binding energies of pure polyacrylamide (PAM), hydrolysed polyacrylamide in neutral form (HPAM), hydrolysed polyacrylamide with 33% charge density (HPAM 33%) and sulfonated polyacrylamide with 33% charge density (SPAM 33%) are assessed to determine the adsorption characteristics onto calcite surfaces. An adsorption-free energy analysis, using an enhanced umbrella sampling method, is applied to evaluate the chemical adsorption performance. The interaction energy analysis shows that the polyacrylamide-based polymers display favourable interactions with the calcite structure. This is attributed to the electrostatic attraction between the amide and carboxyl functional groups with the calcite. Simulations confirm that HPAM33% has a lower free energy than other polymers, presumably due to the presence of the acrylate monomer in ionised form. The superior chemical adsorption performance of HPAM33% agrees with Atomic Force Microscopy experiments reported herein.
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Affiliation(s)
- Keat Yung Hue
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (K.Y.H.); (J.H.L.); (O.K.M.); (P.F.L.)
| | - Jin Hau Lew
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (K.Y.H.); (J.H.L.); (O.K.M.); (P.F.L.)
| | - Maung Maung Myo Thant
- PETRONAS Research Sdn. Bhd., Lot 3288 & 3289, Off Jalan Ayer Itam, Kawasan Institusi Bangi, Kajang 43000, Selangor, Malaysia;
| | - Omar K. Matar
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (K.Y.H.); (J.H.L.); (O.K.M.); (P.F.L.)
| | - Paul F. Luckham
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (K.Y.H.); (J.H.L.); (O.K.M.); (P.F.L.)
| | - Erich A. Müller
- Department of Chemical Engineering, Imperial College London, London SW7 2AZ, UK; (K.Y.H.); (J.H.L.); (O.K.M.); (P.F.L.)
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Knight BM, Edgar KJ, De Yoreo JJ, Dove PM. Chitosan as a Canvas for Studies of Macromolecular Controls on CaCO 3 Biological Crystallization. Biomacromolecules 2023; 24:1078-1102. [PMID: 36853173 DOI: 10.1021/acs.biomac.2c01394] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
A mechanistic understanding of how macromolecules, typically as an organic matrix, nucleate and grow crystals to produce functional biomineral structures remains elusive. Advances in structural biology indicate that polysaccharides (e.g., chitin) and negatively charged proteoglycans (due to carboxyl, sulfate, and phosphate groups) are ubiquitous in biocrystallization settings and play greater roles than currently recognized. This review highlights studies of CaCO3 crystallization onto chitinous materials and demonstrates that a broader understanding of macromolecular controls on mineralization has not emerged. With recent advances in biopolymer chemistry, it is now possible to prepare chitosan-based hydrogels with tailored functional group compositions. By deploying these characterized compounds in hypothesis-based studies of nucleation rate, quantitative relationships between energy barrier to crystallization, macromolecule composition, and solvent structuring can be determined. This foundational knowledge will help researchers understand composition-structure-function controls on mineralization in living systems and tune the designs of new materials for advanced applications.
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Affiliation(s)
- Brenna M Knight
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Department of Geosciences, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - Kevin J Edgar
- Department of Sustainable Biomaterials, Virginia Tech, Blacksburg, Virginia 24061, United States
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
| | - James J De Yoreo
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Patricia M Dove
- Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States
- Macromolecules Innovation Institute, Virginia Tech, Blacksburg, Virginia 24061, United States
- Department of Geosciences, Virginia Tech, Blacksburg, Virginia 24061, United States
- Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061, United States
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8
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Barua B, Durkin TJ, Beeley IM, Gadh A, Savagatrup S. Multiplexed and continuous microfluidic sensors using dynamic complex droplets. SOFT MATTER 2023; 19:1930-1940. [PMID: 36807488 DOI: 10.1039/d3sm00074e] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Emissive complex droplets with reconfigurable morphology and dynamic optical properties offer exciting opportunities as chemical sensors due to their stimuli-responsive characteristics. In this work, we demonstrated a real-time optical sensing platform that combines poly(dimethylsiloxane) (PDMS) microfluidics and complex droplets as sensing materials. We utilized a mechanism, called directional emission, to transduce changes in interfacial tension into optical signals. We discuss the fabrication and integration of PDMS microfluidics with complex emulsions to facilitate continuous measurement of fluorescent emission and, ultimately, the interfacial tensions. Furthermore, by varying the interfacial functionalization and fluorescent dye with characteristic wavelength, we generate multiple formulations of droplets and obtain differential responses to stimuli that alter interfacial tensions (i.e., composition of surfactants, pH). Our results illustrate a proof-of-concept multiplexed and continuous sensing platform with potential applications in miniaturized, on-site environmental monitoring and biosensing.
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Affiliation(s)
- Baishali Barua
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, USA.
| | - Tyler J Durkin
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, USA.
| | - Isabel M Beeley
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, USA.
| | - Aakanksha Gadh
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, USA.
| | - Suchol Savagatrup
- Department of Chemical and Environmental Engineering, University of Arizona, 1133 E. James E. Rogers Way, Tucson, Arizona 85721, USA.
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9
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Eltaboni F, Singh S, Swanson L, Swift T, Almalki AS. Fluorescence spectroscopy analysis of fly ash removal from aqueous systems: adsorption of alginate to silica and alumina. SOFT MATTER 2022; 18:5687-5698. [PMID: 35861613 DOI: 10.1039/d2sm00558a] [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
Fly ash is a toxic industrial waste, mainly consisting of silica and alumina particles, that has been found discharged into the environment. It is proposed that alginate, a naturally occurring biopolymer, can bind to these minerals and thus play a role in water purification. The binding forces involved in this process consist of weak interactions, such as van der Waals forces and electrostatic interactions. Although the attachment of alginate to mineral surfaces is mainly governed by its carboxylate groups, hydroxyl moieties could play a role in the interaction between the polymer and minerals. This work aims to use the SiO2 and Al2O3 particles as models for fly ash and to show the use of alginate biopolymers (fluorescently labelled with an aminonaphthaline sulfonate fluorophore (AmNS)) to coagulate them. The addition of simple electrolytes like NaCl and CaCl2 encourages the coiling of the polymer chain at high pH values which has an effect on its capability to bind to the inorganic particles. A combination of fluorescence and ICP-MS demonstrated that alginate has a considerable adsorption affinity for Al2O3, whereas it attracts SiO2 weakly. The adsorption process is pH dependent: strong adsorption was observed at low pH values. The dependence of adsorption on the mineral (Al2O3 and SiO2) concentration was also examined under different pH conditions: the adsorption amount was observed to increase by increasing the solid concentration. Adsorption isotherms obtained at low and high mineral concentrations were found to be Henry in type.
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Affiliation(s)
- Fateh Eltaboni
- Department of Chemistry, University of Benghazi, Benghazi, Libya.
| | - Sehaj Singh
- School of Chemistry and Biosciences, University of Bradford, Bradford BD7 1DP, UK
| | - Linda Swanson
- Department of Chemistry, The University of Sheffield, Sheffield S10 2TN, UK
| | - Thomas Swift
- School of Chemistry and Biosciences, University of Bradford, Bradford BD7 1DP, UK
| | - Abdulraheem Sa Almalki
- Department of Chemistry, Faculty of Science, Taif University, Taif, Kingdom of Saudi Arabia
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Combined in-situ attenuated total reflection-Fourier transform infrared spectroscopy and single molecule force studies of poly(acrylic acid) at electrolyte/oxide interfaces at acidic pH. J Colloid Interface Sci 2022; 615:563-576. [DOI: 10.1016/j.jcis.2022.01.175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 01/15/2022] [Accepted: 01/26/2022] [Indexed: 11/20/2022]
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11
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Reducing anionic surfactant adsorption using polyacrylate as sacrificial agent investigated by QCM-D. J Colloid Interface Sci 2021; 585:1-11. [DOI: 10.1016/j.jcis.2020.11.090] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 11/15/2020] [Accepted: 11/23/2020] [Indexed: 11/21/2022]
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12
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Marine Exopolysaccharide Complexed With Scandium Aimed as Theranostic Agents. Molecules 2021; 26:molecules26041143. [PMID: 33672781 PMCID: PMC7924592 DOI: 10.3390/molecules26041143] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/16/2021] [Accepted: 02/18/2021] [Indexed: 12/27/2022] Open
Abstract
(1) Background: Exopolysaccharide (EPS) derivatives, produced by Alteromonas infernus bacterium, showed anti-metastatic properties. They may represent a new class of ligands to be combined with theranostic radionuclides, such as 47Sc/44Sc. The goal of this work was to investigate the feasibility of such coupling. (2) Methods: EPSs, as well as heparin used as a drug reference, were characterized in terms of molar mass and dispersity using Asymmetrical Flow Field-Flow Fractionation coupled to Multi-Angle Light Scattering (AF4-MALS). The intrinsic viscosity of EPSs at different ionic strengths were measured in order to establish the conformation. To determine the stability constants of Sc with EPS and heparin, a Free-ion selective radiotracer extraction (FISRE) method has been used. (3) Results: AF4-MALS showed that radical depolymerization produces monodisperse EPSs, suitable for therapeutic use. EPS conformation exhibited a lower hydrodynamic volume for the highest ionic strengths. The resulting random-coiled conformation could affect the complexation with metal for high concentration. The LogK of Sc-EPS complexes have been determined and showing that they are comparable to the Sc-Hep. (4) Conclusions: EPSs are very promising to be coupled with the theranostic pair of scandium for Nuclear Medicine.
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Badizad MH, Koleini MM, Greenwell HC, Ayatollahi S, Ghazanfari MH, Mohammadi M. Ion-specific interactions at calcite-brine interfaces: a nano-scale study of the surface charge development and preferential binding of polar hydrocarbons. Phys Chem Chem Phys 2020; 22:27999-28011. [PMID: 33300538 DOI: 10.1039/d0cp04828c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This research provides an atomic-level insight into the synergic contribution of mono- and divalent ions to interfacial characteristics of calcite surfaces exposed to electrolyte solution containing organic compounds. The emphasis was placed on the ionic interactions responsible for charge developing mechanisms of calcite surfaces and also the capacity for adsorption of polar hydrocarbons, represented by benzoic acid (BA), at different brine compositions. For this purpose, molecular dynamics (MD) simulations were employed to explore the interplay of the main constituent ions of natural brines (Na+, Cl-, Mg2+, and SO42-) and BA at the interface of CaCO3. It was observed that surface accumulation of Na+ cations produces a positively charged layer immediate to the basal plane of calcite, validating the typical positive surface charge of carbonates reported by laboratory experiences. Meanwhile, a negatively charged layer appears beyond the sodium layer as a result of direct and solvent-mediated pairing of anions with Na+ cations lodged on the calcite substrate. In this process, sulfate adsorption severely diminishes surface charge to even a negative value in the case of a SO42--rich solution, providing an interpretation for the measurements reported in the literature. Our results revealed the inhibition of direct binding of BA molecules onto the calcite surface through complexation with protruding oxygen atoms of basal carbonates by the residing Na+ cations. Further, we noticed the sulfate-mediated pairing of BA molecules to the Na+ layer, which in effect intensifies surface adsorption of BA. However, BA-SO42- interaction is considerably reduced by magnesium cations shielding sulfate sites in the Mg2+-augmented brine. The findings presented in this study are of fundamental importance to advance our microscopic understanding of interfacial interactions in brine/oil/carbonate systems; with broad scientific and applied implications in the context of mobilizing organic contaminants trapped in aquifer sediments and enhancement of hydrophilicity of subsurface oil-bearing carbonate reservoirs by injecting ion-modified brine solutions.
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14
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Robust Hydrophobic Coatings Using Polymer Blends for the Surface Protection of Marble. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.124796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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15
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Ranoo S, Lahiri BB, Nandy M, Philip J. Enhanced magnetic heating efficiency at acidic pH for magnetic nanoemulsions stabilized with a weak polyelectrolyte. J Colloid Interface Sci 2020; 579:582-597. [PMID: 32623124 DOI: 10.1016/j.jcis.2020.06.093] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/08/2020] [Accepted: 06/22/2020] [Indexed: 02/02/2023]
Abstract
HYPOTHESIS Magnetic fluid hyperthermia has attracted considerable attention for cancer therapeutics. Magnetic nanoemulsions are potential candidates for multi-modal hyperthermia due to the possibility of volumetric loading with suitable chemo/photo-therapy agents. Often, the nanocarriers are stabilized using organic molecules that behave differently under varying pH and hence, an understanding of their interfacial behaviour is important for practical applications. EXPERIMENTS We probe the magnetic heating efficiency of poly acrylic acid (PAA) stabilized oil-in-water magnetic nanoemulsions, as a function of pH, where the conformational changes of the PAA molecules are studied using dynamic light scattering and inter-droplet force measurements. FINDINGS A ~50% enhanced heating efficiency is observed when solution pH is reduced from ~9 to 3, which is attributed to the coil-to-globule conformational changes of the PAA molecules. The increased ionization of the carboxylic acid groups, at higher pH, leads to reduced hydrophobicity that results in an increase in the interfacial thermal resistance causing a lower magneto-thermal heating efficiency at higher pH. The proposed interfacial heat transfer hypothesis is experimentally verified using thermal imaging, where a lower rate of heat transfer is obtained at higher pH. The observed enhanced hyperthermia efficiency at low pH is beneficial for designing efficient pH-responsive nano-carriers for multi-modal hyperthermia.
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Affiliation(s)
- Surojit Ranoo
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India
| | - B B Lahiri
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India.
| | - Manali Nandy
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India
| | - John Philip
- Smart Materials Section, Corrosion Science and Technology Division, Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, HBNI, Kalpakkam, Tamil Nadu 603102, India.
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16
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El-Taboni F, Caseley E, Katsikogianni M, Swanson L, Swift T, Romero-González ME. Fluorescence Spectroscopy Analysis of the Bacteria-Mineral Interface: Adsorption of Lipopolysaccharides to Silica and Alumina. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:1623-1632. [PMID: 31957449 PMCID: PMC7145363 DOI: 10.1021/acs.langmuir.9b02158] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We present here a quantification of the sorption process and molecular conformation involved in the attachment of bacterial cell wall lipopolysaccharides (LPSs), extracted from Escherichia coli, to silica (SiO2) and alumina (Al2O3) particles. We propose that interfacial forces govern the physicochemical interactions of the bacterial cell wall with minerals in the natural environment, and the molecular conformation of LPS cell wall components depends on both the local charge at the point of binding and hydrogen bonding potential. This has an effect on bacterial adaptation to the host environment through adhesion, growth, function, and ability to form biofilms. Photophysical techniques were used to investigate adsorption of fluorescently labeled LPS onto mineral surfaces as model systems for bacterial attachment. Adsorption of macromolecules in dilute solutions was studied as a function of pH and ionic strength in the presence of alumina and silica via fluorescence, potentiometric, and mass spectrometry techniques. The effect of silica and alumina particles on bacterial growth as a function of pH was also investigated using spectrophotometry. The alumina and silica particles were used to mimic active sites on the surface of clay and soil particles, which serve as a point of attachment of bacteria in natural systems. It was found that LPS had a high adsorption affinity for Al2O3 while adsorbing weakly to SiO2 surfaces. Strong adsorption was observed at low pH for both minerals and varied with both pH and mineral concentration, likely in part due to conformational rearrangement of the LPS macromolecules. Bacterial growth was also enhanced in the presence of the particles at low pH values. This demonstrates that at a molecular level, bacterial cell wall components are able to adapt their conformation, depending on the solution pH, in order to maximize attachment to substrates and guarantee community survival.
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Affiliation(s)
- Fateh El-Taboni
- Department
of Chemistry, University of Benghazi, Benghazi Qar Yunis 9480, Libya
| | - Emily Caseley
- School
of Chemistry and Biosciences, University
of Bradford, Bradford BD7 1DP, U.K.
| | - Maria Katsikogianni
- School
of Chemistry and Biosciences, University
of Bradford, Bradford BD7 1DP, U.K.
| | - Linda Swanson
- Department
of Chemistry, The University of Sheffield, Sheffield S10 2TN, U.K.
| | - Thomas Swift
- School
of Chemistry and Biosciences, University
of Bradford, Bradford BD7 1DP, U.K.
- E-mail: (T.S.)
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The Combined Effects of Sr(II) and Poly(Acrylic Acid) on the Morphology of Calcite. MATERIALS 2019; 12:ma12203339. [PMID: 31614936 PMCID: PMC6829221 DOI: 10.3390/ma12203339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 10/04/2019] [Accepted: 10/10/2019] [Indexed: 12/12/2022]
Abstract
Biomineralization of calcium carbonate has interesting characteristics of intricate morphology formation with controlled crystal polymorphs. In particular, modification of calcite morphology with diverse additives has been the focus of many biomimetic and bioinspired studies. The possible role of strontium ions in enhancing the morphology-modifying ability of macromolecules was investigated. In the present study, concentrations of strontium ions were comparable to that in seawater, and anionic poly(acrylic acid) and cationic poly(ethylene imine) were used as model macromolecules. When strontium ions were combined with anionic poly(acrylic acid), new types of calcite surfaces, most likely {hk0}, appeared to drastically change the morphology of the crystals, which was not observed with cationic poly(ethylene imine). This behavior of strontium ions was quite similar to that of magnesium ions, which is intriguing because both ions are available from seawater to be utilized during biomineralization.
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18
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Zaibudeen A, Philip J. Adsorption of bovine serum albumin at oil-water interface in the presence of polyelectrolytes and nature of interaction forces. Colloids Surf A Physicochem Eng Asp 2019. [DOI: 10.1016/j.colsurfa.2019.01.014] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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19
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Kyrychenko A, Blazhynska MM, Slavgorodska MV, Kalugin ON. Stimuli-responsive adsorption of poly(acrylic acid) onto silver nanoparticles: Role of polymer chain length and degree of ionization. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2018.11.130] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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20
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Zhao H, Yang Y, Wang Y, Shu X, Wu S, Ran Q, Liu J. Binding of calcium cations with three different types of oxygen-based functional groups of superplasticizers studied by atomistic simulations. J Mol Model 2018; 24:321. [PMID: 30357533 DOI: 10.1007/s00894-018-3853-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 10/04/2018] [Indexed: 11/29/2022]
Abstract
This work investigated interactions between calcium cations (Ca2+) and three common types of oxygen-based functional groups of concrete superplasticizers using density functional theory (DFT) calculations and all-atom molecular dynamics (MD) simulations. The three common types of oxygen-based functional groups were modeled as three hypothetical, low-molecular-weight organic molecules, each containing a methyl-terminated oxyethylene dimer and an adsorbing head of two oxygen-based functional groups, and are referred to as carboxylate, sulfonate, and phosphate groups, respectively, following the usual terminology in the field of concrete admixtures. Our DFT results show that the binding strength of the three groups with calcium cations follows (from high to low) phosphate>carboxylate>sulfonate, and both the electrophilic attack and the chemical reactivity of the three groups contribute significantly to the binding strength. The MD simulation results indicate that the adsorption of the three small molecules on the calcite (1 0 4) surface in aqueous solution shares a similar pattern in the sense that just two oxygen atoms of two adjacent anchor groups adsorb on the calcium atoms on the top layer of the crystal. The adsorption strength among the three types of functional groups follows the same order as the binding strength obtained from DFT calculations; both results corroborate a similar rule-of-thumb established by experiments. Furthermore, interactions of the three types of groups with water molecules suggest that strong hydrogen-bonding interactions exist in those systems. Graphical abstract Binding of calcium cations with three different types of oxygen-based functional groups of superplasticizersᅟ.
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Affiliation(s)
- Hongxia Zhao
- State Key Laboratory of High Performance Civil Engineering Materials, Jiangsu Sobute New Materials Co., Ltd., Nanjing, 210008, Jiangsu, China
| | - Yong Yang
- State Key Laboratory of High Performance Civil Engineering Materials, Jiangsu Sobute New Materials Co., Ltd., Nanjing, 210008, Jiangsu, China
| | - Yanwei Wang
- State Key Laboratory of High Performance Civil Engineering Materials, Jiangsu Sobute New Materials Co., Ltd., Nanjing, 210008, Jiangsu, China
| | - Xin Shu
- State Key Laboratory of High Performance Civil Engineering Materials, Jiangsu Sobute New Materials Co., Ltd., Nanjing, 210008, Jiangsu, China
| | - Shishan Wu
- School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210093, China
| | - Qianping Ran
- State Key Laboratory of High Performance Civil Engineering Materials, Jiangsu Sobute New Materials Co., Ltd., Nanjing, 210008, Jiangsu, China.
| | - Jiaping Liu
- School of Material Science and Engineering, Southeast University, Nanjing, 211189, Jiangsu, China.
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Behavior of a strong polyelectrolyte, poly(diallyldimethylammonium chloride) physisorbed at oil-water interface under different environments : A comparison with a weak polyelectrolyte. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2018.04.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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22
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Zhao H, Yang Y, Shu X, Wang Y, Ran Q. Adsorption of organic molecules on mineral surfaces studied by first-principle calculations: A review. Adv Colloid Interface Sci 2018; 256:230-241. [PMID: 29656761 DOI: 10.1016/j.cis.2018.04.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 11/16/2022]
Abstract
First-principle calculations, especially by the density functional theory (DFT) methods, are becoming a power technique to study molecular structure and properties of organic/inorganic interfaces. This review introduces some recent examples on the study of adsorption models of organic molecules or oligomers on mineral surfaces and interfacial properties obtained from first-principles calculations. The aim of this contribution is to inspire scientists to benefit from first-principle calculations and to apply the similar strategies when studying and tailoring interfacial properties at the atomistic scale, especially for those interested in the design and development of new molecules and new products.
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Affiliation(s)
- Hongxia Zhao
- State Key Laboratory of High Performance Civil Engineering Materials, Nanjing 210008, Jiangsu, China; Jiangsu Sobute New Materials Co. Ltd., Nanjing 211103, Jiangsu, China
| | - Yong Yang
- State Key Laboratory of High Performance Civil Engineering Materials, Nanjing 210008, Jiangsu, China; Jiangsu Sobute New Materials Co. Ltd., Nanjing 211103, Jiangsu, China
| | - Xin Shu
- State Key Laboratory of High Performance Civil Engineering Materials, Nanjing 210008, Jiangsu, China; Jiangsu Sobute New Materials Co. Ltd., Nanjing 211103, Jiangsu, China
| | - Yanwei Wang
- State Key Laboratory of High Performance Civil Engineering Materials, Nanjing 210008, Jiangsu, China; Jiangsu Sobute New Materials Co. Ltd., Nanjing 211103, Jiangsu, China.
| | - Qianping Ran
- State Key Laboratory of High Performance Civil Engineering Materials, Nanjing 210008, Jiangsu, China; Jiangsu Sobute New Materials Co. Ltd., Nanjing 211103, Jiangsu, China.
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Fornefett I, Buttersack C. Exo-enzyme like degradation of a polysaccharide by an inorganic solid acid catalyst. Carbohydr Polym 2018; 187:126-132. [DOI: 10.1016/j.carbpol.2018.01.064] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/10/2018] [Accepted: 01/20/2018] [Indexed: 10/18/2022]
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Kanematsu M, Waychunas GA, Boily JF. Silicate Binding and Precipitation on Iron Oxyhydroxides. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:1827-1833. [PMID: 29303566 DOI: 10.1021/acs.est.7b04098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Silica-bearing waters in nature often alter the reactivity of mineral surfaces via deposition of Si complexes and solids. In this work, Fourier transform infrared (FTIR) spectroscopy was used to identify hydroxo groups at goethite (α-FeOOH) and lepidocrocite (γ-FeOOH) surfaces that are targeted by ligand exchange reactions with monomeric silicate species. Measurements of samples first reacted in aqueous solutions then dried under N2(g) enabled resolution of the signature O-H stretching bands of singly (-OH), doubly (μ-OH), and triply coordinated (μ3-OH) groups. Samples reacted with Si for 3 and 30 d at pH 4 and 7 revealed that -OH groups were preferentially exchanged by silicate and that μ-OH and μ3-OH groups were not exchanged. Based on knowledge of the disposition of -OH groups on the major crystallographic faces of goethite and lepidocrocite, and the response of these groups to ligand exchange prior oligomerization, our work points to the predominance of rows of mononuclear monodentate silicate species, each separated by at least one -OH group. These species are the attachment sites from which oligomerization and polymerization reactions occur, starting at loadings exceeding ∼1 Si/nm2 and corresponding to soluble Si concentrations that can be as low as ∼0.7 mM after 30 d reaction time. Only above such loadings can reaction products grow away from rows of -OH groups and form hydrogen bonds with nonexchangeable μ-OH and μ3-OH groups. These findings have important repercussions for our understanding of the fate of waterborne silicate ions exposed to minerals.
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Affiliation(s)
- Masakazu Kanematsu
- Energy Geosciences Division, Lawrence Berkeley National Laboratory , One Cyclotron Road, Berkeley, California 94720, United States
- Department of Chemistry, Umeå University , SE-901 87 Umeå, Sweden
| | - Glenn A Waychunas
- Energy Geosciences Division, Lawrence Berkeley National Laboratory , One Cyclotron Road, Berkeley, California 94720, United States
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25
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Zaibudeen A, Philip J. A spectroscopic approach to probe macromolecular conformational changes at interface under different environmental conditions: A case study with PAA adsorbed at oil-water Interface. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2017.12.090] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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26
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Behavior of a Weak Polyelectrolyte at Oil-water Interfaces under Different Environmental Conditions. Colloids Surf A Physicochem Eng Asp 2018. [DOI: 10.1016/j.colsurfa.2017.11.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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27
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Karatasos K, Kritikos G. A microscopic view of graphene-oxide/poly(acrylic acid) physical hydrogels: effects of polymer charge and graphene oxide loading. SOFT MATTER 2018; 14:614-627. [PMID: 29265164 DOI: 10.1039/c7sm02305g] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this work we have examined in detail by means of fully atomistic molecular dynamics simulations, physical hydrogels formed by a polymer electrolyte, poly(acrylic acid), and graphene oxide, at two different charging states of the polymer and two different graphene oxide concentrations. It was found that variations of these parameters incurred drastic changes in general morphological characteristics of the composite materials, the degree of physical adsorption of polyelectrolyte chains onto the graphene oxide surface, the polymer dynamic response at local and global length scales, in the charge distributions around the components, and in the mobility of the counterions. All these microscopic features are expected to significantly affect macroscopic physical properties of the hydrogels, such as their mechanical responses and their electrical behaviors.
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Affiliation(s)
- Kostas Karatasos
- Laboratory of Physical Chemistry, Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
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28
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Swift T, Seaton CC, Rimmer S. Poly(acrylic acid) interpolymer complexes. SOFT MATTER 2017; 13:8736-8744. [PMID: 29119179 DOI: 10.1039/c7sm01787a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Interpolymer complex formation of poly(acrylic acid) with other macromolecules can occur via several mechanisms that vary depending on the pH. At low pH the protonated acid functional group can form bonds with both donor and acceptor moieties, resulting in desolvated structures consisting of two polymers. Complexes were formed in dilute solutions of PAA, functionalised with acenaphthylene, with a range of other polymers including: poly(NIPAM); poly(ethylene oxide) (PEO); poly(dimethylacrylamide) (PDMA); poly(diethyl acrylamide) (PDEAM) poly(vinyl alcohol) (PVA) and poly(vinyl pyrolidinone) (PVP). Fluorescence anisotropy was used to demonstrate complex formation in each case by monitoring the reductions in segmental motion of the chain as the complexes formed. Considerations of the molecular structures of the complexing moieties suggest that solvation energies and pKas play an important role in complex formation.
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Affiliation(s)
- Thomas Swift
- School of Chemistry and Biosciences, University of Bradford, Bradford, West Yorkshire BD7 1DP, UK.
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29
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Kim YY, Freeman CL, Gong X, Levenstein MA, Wang Y, Kulak A, Anduix-Canto C, Lee PA, Li S, Chen L, Christenson HK, Meldrum FC. The Effect of Additives on the Early Stages of Growth of Calcite Single Crystals. Angew Chem Int Ed Engl 2017; 56:11885-11890. [PMID: 28767197 PMCID: PMC5638089 DOI: 10.1002/anie.201706800] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Indexed: 01/28/2023]
Abstract
As crystallization processes are often rapid, it can be difficult to monitor their growth mechanisms. In this study, we made use of the fact that crystallization proceeds more slowly in small volumes than in bulk solution to investigate the effects of the soluble additives Mg2+ and poly(styrene sulfonate) (PSS) on the early stages of growth of calcite crystals. Using a “Crystal Hotel” microfluidic device to provide well‐defined, nanoliter volumes, we observed that calcite crystals form via an amorphous precursor phase. Surprisingly, the first calcite crystals formed are perfect rhombohedra, and the soluble additives have no influence on the morphology until the crystals reach sizes of 0.1–0.5 μm for Mg2+ and 1–2 μm for PSS. The crystals then continue to grow to develop morphologies characteristic of these additives. These results can be rationalized by considering additive binding to kink sites, which is consistent with crystal growth by a classical mechanism.
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Affiliation(s)
- Yi-Yeoun Kim
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Colin L Freeman
- Department of Materials Science and Engineering, University of Sheffield, Sheffield, S1 3JD, UK
| | - Xiuqing Gong
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK.,Current address: Materials Genome Institute, Shanghai University, Shanghai, 200444, China
| | - Mark A Levenstein
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK.,School of Mechanical Engineering, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Yunwei Wang
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Alexander Kulak
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Clara Anduix-Canto
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Phillip A Lee
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Shunbo Li
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
| | - Li Chen
- Institute of Microwaves & Photonics, School of Electronic & Electrical Engineering, University of Leeds, Leeds, LS2 9JT, UK
| | - Hugo K Christenson
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, UK
| | - Fiona C Meldrum
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, UK
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The Effect of Additives on the Early Stages of Growth of Calcite Single Crystals. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201706800] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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31
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Swift T, Paul N, Swanson L, Katsikogianni M, Rimmer S. Förster Resonance Energy Transfer across interpolymer complexes of poly(acrylic acid) and poly(acrylamide). POLYMER 2017. [DOI: 10.1016/j.polymer.2017.06.069] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Molecular Dynamics Simulation to Understand the Ability of Anionic Polymers to Alter the Morphology of Calcite. INT J POLYM SCI 2017. [DOI: 10.1155/2017/7594950] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Molecular dynamics was utilized to investigate the ability of anionic macromolecules to drastically change the morphology of calcite in the presence of magnesium ions. Anionic poly(acrylic acid) and poly(methacrylic acid) were compared with cationic poly(ethylene imine) in their binding behavior on calcite (104) and (110) surfaces. Poly(acrylic acid) and poly(methacrylic acid) showed preferential binding on (110) with strong electrostatic attractions, whereas poly(ethylene imine) was only weakly attracted to (104). The extent of the charge imbalance on the surfaces appeared responsible for the current results, which originated from the deficient number of the coordinating oxygen atoms of carbonate around the surface calcium. The results of the current study were in accordance with the previous experimental observations, where the {hk0} surfaces of calcite were elongated under the coexistence of the anionic polymers and magnesium ions. These results could be generally utilized in the polymer-controlled crystallization with broad implications in the specific interactions with crystal surfaces.
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34
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Konduri MK, Fatehi P. Synthesis and characterization of carboxymethylated xylan and its application as a dispersant. Carbohydr Polym 2016; 146:26-35. [DOI: 10.1016/j.carbpol.2016.03.036] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2016] [Revised: 03/13/2016] [Accepted: 03/16/2016] [Indexed: 11/16/2022]
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35
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Karatasos K, Kritikos G. Characterization of a graphene oxide/poly(acrylic acid) nanocomposite by means of molecular dynamics simulations. RSC Adv 2016. [DOI: 10.1039/c6ra22951d] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Graphene oxide/poly(acrylic acid) nanocomposite: static, dynamic, thermal properties and hydrogen bonding, as studied by molecular dynamics simulations.
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Affiliation(s)
- Kostas Karatasos
- Laboratory of Physical Chemistry
- Department of Chemical Engineering
- Aristotle University of Thessaloniki
- 54124 Thessaloniki
- Greece
| | - Georgios Kritikos
- Laboratory of Physical Chemistry
- Department of Chemical Engineering
- Aristotle University of Thessaloniki
- 54124 Thessaloniki
- Greece
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