1
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Murugapandian R, Mohan SG, T M S, Nambi Raj NA, Uthirapathy V. Comparative Analysis of Electrospun Silk Fibroin/Chitosan Sandwich-Structured Scaffolds for Osteo Regeneration: Evaluating Mechanical Properties, Biological Performance, and Drug Release. ACS OMEGA 2024; 9:28072-28092. [PMID: 38973883 PMCID: PMC11223251 DOI: 10.1021/acsomega.4c01069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 05/15/2024] [Accepted: 05/21/2024] [Indexed: 07/09/2024]
Abstract
An intensive idea of bone tissue engineering is to design regenerative nanofibrous scaffolds that could afford a natural extracellular matrix (ECM) microenvironment with the ability to induce cell proliferation, biodegradation, sustained drug release, and bioactivity. Even the mechanical properties and orientation of the nanofibers may enhance the performance of the scaffolds. To address this issue, we designed novel sandwich-like hybrid silk fibroin (SF)/silica/poly(vinyl alcohol) (PVA) nanofibers scaffolds. The developed scaffold was further characterized using scanning electron microscopy (SEM), elemental mapping, X-ray diffraction (XRD), Fourier-transform infrared (FTIR), and water/blood contact angle measurements. Owing to the interfacial interaction between the layers of organic (chitosan/silk fibroin) and inorganic (silica) in the nanofibrous scaffold, a biocompatibility study has been made on an osteoblast-like (MG63) cell line, which has significant statistical differences; hemocompatibility and the mechanical profile were evaluated in detail to understand the suitability as a biomaterial. To endow the scaffold biodegradation rate, antibacterial activity, porosity profile, and cephalexin monohydrate (CEM), a drug-loading/drug release study was also performed for all of the nanofibers. This strategy explored superior mechanical strength with higher biomineralization on SF/silica/PVA nanofibers. Eventually, the proposed article compared the observation of monolayered scaffolds with designed sandwich-structured scaffolds for the enhancement of bone regeneration.
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Affiliation(s)
- Rama Murugapandian
- Centre
for Nonlinear Systems, Chennai Institute
of Technology, Chennai 600069, India
| | | | - Sridhar T M
- Department
of Analytical Chemistry, University of Madras, Chennai 600025, India
| | - N. Arunai Nambi Raj
- Centre
for Biomaterials, Cellular and Molecular Theragnostic, Vellore Institute of Technology, Vellore 632 014, India
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2
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Ilgen AG, Borguet E, Geiger FM, Gibbs JM, Grassian VH, Jun YS, Kabengi N, Kubicki JD. Bridging molecular-scale interfacial science with continuum-scale models. Nat Commun 2024; 15:5326. [PMID: 38909017 PMCID: PMC11193788 DOI: 10.1038/s41467-024-49598-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 06/07/2024] [Indexed: 06/24/2024] Open
Abstract
Solid-water interfaces are crucial for clean water, conventional and renewable energy, and effective nuclear waste management. However, reflecting the complexity of reactive interfaces in continuum-scale models is a challenge, leading to oversimplified representations that often fail to predict real-world behavior. This is because these models use fixed parameters derived by averaging across a wide physicochemical range observed at the molecular scale. Recent studies have revealed the stochastic nature of molecular-level surface sites that define a variety of reaction mechanisms, rates, and products even across a single surface. To bridge the molecular knowledge and predictive continuum-scale models, we propose to represent surface properties with probability distributions rather than with discrete constant values derived by averaging across a heterogeneous surface. This conceptual shift in continuum-scale modeling requires exponentially rising computational power. By incorporating our molecular-scale understanding of solid-water interfaces into continuum-scale models we can pave the way for next generation critical technologies and novel environmental solutions.
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Affiliation(s)
- Anastasia G Ilgen
- Geochemistry Department, Sandia National Laboratories, Albuquerque, NM, 87123, USA.
| | - Eric Borguet
- Department of Chemistry, Temple University, Philadelphia, PA, 19122, USA
| | - Franz M Geiger
- Department of Chemistry, Northwestern University, Evanston, IL, 60208, USA
| | - Julianne M Gibbs
- Department of Chemistry, University of Alberta, Edmonton, AB, T6G 2G2, Canada
| | - Vicki H Grassian
- Department of Chemistry and Biochemistry, University of California, La Jolla, CA, 92093, USA
| | - Young-Shin Jun
- Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO, 63130, USA
| | - Nadine Kabengi
- Department of Geosciences, Georgia State University, Atlanta, GA, 30302, USA
| | - James D Kubicki
- Department of Earth, Environmental and Resource Sciences, The University of Texas at El Paso, El Paso, TX, 79968, USA
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3
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Mahović Poljaček S, Priselac D, Tomašegović T, Leskovac M, Šoster A, Stanković Elesini U. Quantitative Analysis of Morphology and Surface Properties of Poly(lactic acid)/Poly(ε-caprolactone)/Hydrophilic Nano-Silica Blends. Polymers (Basel) 2024; 16:1739. [PMID: 38932088 PMCID: PMC11207708 DOI: 10.3390/polym16121739] [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: 05/22/2024] [Revised: 06/14/2024] [Accepted: 06/18/2024] [Indexed: 06/28/2024] Open
Abstract
A quantitative analysis of the morphology, as well as an analysis of the distribution of components and surface/interfacial properties in poly(lactic acid)(PLA) InegoTM 3251D, poly(ε-caprolactone) (PCL) Capa 6800 and nano-silica (SiO2) Aerosil®200 blends, was conducted in this research. The study aimed to improve the understanding of how PLA, PCL, and nano-SiO2 interact, resulting in the specific morphology and surface properties of the blends. Samples were produced by varying the concentration of all three components. They were analyzed using SEM, EDS mapping, water contact angle measurements, surface free energy calculation, adhesion parameter measurements, and FTIR-ATR spectroscopy. The results showed that the addition of SiO2 nanoparticles led to an increase in the contact angle of water, making the surface more hydrophobic. SEM images of the blends showed that increasing the PCL content reduced the size of spherical PCL elements in the blends. FTIR-ATR analysis showed that SiO2 nanoparticles influenced the structure ordering of PLA in the blend with equal portions of PLA and PCL. In the samples with a higher PCL content, the spherical elements present in the samples with a higher PLA/PCL ratio have been reduced, indicating better interactions at the interface between PLA, PCL, and SiO2. SEM-EDS mapping of the PLA/PCL 100/0 blend surfaces revealed the presence of SiO2 clusters and the silicon (Si) concentration reaching up to ten times higher than the nominal concentration of SiO2. However, with the addition of 3% SiO2 to the blend containing PCL, the structure became more granular. Specifically, Si protrusions in the sample PLA/PCL 90/10 with 3% SiO2 displayed 29.25% of Si, and the sample PLA/PCL 70/30 with 3% SiO2 displayed an average of 10.61% of Si at the protrusion locations. The results confirmed the affinity of SiO2 to be encapsulated by PCL. A better understanding of the interactions between the materials in the presented blends and the quantitative analysis of their morphology could improve the understanding of their properties and allow the optimization of their application for different purposes.
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Affiliation(s)
| | - Dino Priselac
- Faculty of Graphic Arts, University of Zagreb, 10000 Zagreb, Croatia;
| | | | - Mirela Leskovac
- Faculty of Chemical Engineering and Technology, University of Zagreb, 10000 Zagreb, Croatia;
| | - Aleš Šoster
- Faculty of Natural Sciences and Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (A.Š.); (U.S.E.)
| | - Urška Stanković Elesini
- Faculty of Natural Sciences and Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia; (A.Š.); (U.S.E.)
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4
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Lu H, Macht M, Rosenberg R, Wiedenbeck E, Lukas M, Qi D, Maltseva D, Zahn D, Cölfen H, Bonn M. Organic Nucleation: Water Rearrangement Reveals the Pathway of Ibuprofen. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2307858. [PMID: 38269485 DOI: 10.1002/smll.202307858] [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: 09/08/2023] [Revised: 12/31/2023] [Indexed: 01/26/2024]
Abstract
The organic nucleation of the pharmaceutical ibuprofen is investigated, as triggered by the protonation of ibuprofen sodium salt at elevated pH. The growth and aggregation of nanoscale solution species by Analytical Ultracentrifugation and Molecular Dynamics (MD) simulations is tracked. Both approaches reveal solvated molecules, oligomers, and prenucleation clusters, their size as well as their hydration at different reaction stages. By combining surface-specific vibrational spectroscopy and MD simulations, water interacting with ibuprofen at the air-water interface during nucleation is probed. The results show the structure of water changes upon ibuprofen protonation in response to the charge neutralization. Remarkably, the water structure continues to evolve despite the saturation of protonated ibuprofen at the hydrophobic interface. This further water rearrangement is associated with the formation of larger aggregates of ibuprofen molecules at a late prenucleation stage. The nucleation of ibuprofen involves ibuprofen protonation and their hydrophobic assembly. The results highlight that these processes are accompanied by substantial water reorganization. The critical role of water is possibly relevant for organic nucleation in aqueous environments in general.
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Affiliation(s)
- Hao Lu
- Department of Materials and Textile Engineering, Nanotechnology Research Institute, Jiaxing University, Jiaxing, Zhejiang Province, 314001, P. R. China
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Moritz Macht
- Lehrstuhl für Theoretische Chemie/Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Rose Rosenberg
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Eduard Wiedenbeck
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Max Lukas
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Daizong Qi
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Daria Maltseva
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Dirk Zahn
- Lehrstuhl für Theoretische Chemie/Computer Chemie Centrum, Friedrich-Alexander Universität Erlangen-Nürnberg, Nägelsbachstraße 25, 91052, Erlangen, Germany
| | - Helmut Cölfen
- Physical Chemistry, Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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5
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Samrout OE, Berlier G, Lambert JF. Amino Acid Polymerization on Silica Surfaces. Chempluschem 2024; 89:e202300642. [PMID: 38226922 DOI: 10.1002/cplu.202300642] [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: 11/11/2023] [Revised: 01/05/2024] [Accepted: 01/15/2024] [Indexed: 01/17/2024]
Abstract
The polymerization of unactivated amino acids (AAs) is an important topic because of its applications in various fields including industrial medicinal chemistry and prebiotic chemistry. Silica as a promoter for this reaction, is of great interest owing to its large abundance and low cost. The amide/peptide bond synthesis on silica has been largely demonstrated but suffers from a lack of knowledge regarding its reaction mechanism, the key parameters, and surface features that influence AA adsorption and reactivity, the selectivity of the reaction product, the role of water in the reaction, etc. The present review addresses these problems by summarizing experimental and modeling results from the literature and attempts to rationalize some apparent divergences in published results. After briefly presenting the main types of silica surface sites and other relevant macroscopic features, we discuss the different deposition procedures of AAs, whose importance is often neglected. We address the possible AA adsorption mechanisms including covalent grafting and H-bonding and show that they are highly dependent on silanol types and density. We then consider how the adsorption mechanisms determine the occurrence and outcome of AA condensation (formation of cyclic dimers or of long linear chains), and outline some recent results that suggest significant polymerization selectivity in systems containing several AAs, as well as the formation of specific elements of secondary structure in the growing polypeptide chains.
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Affiliation(s)
- Ola El Samrout
- Department of Chemistry, University of Torino, Via P. Giuria 7, 10125, Torino, Italy
| | - Gloria Berlier
- Department of Chemistry, University of Torino, Via P. Giuria 7, 10125, Torino, Italy
| | - Jean-François Lambert
- Laboratoire de Réactivité de Surface, LRS, Sorbonne Université Place Jussieu, 75005, Paris, France
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6
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Olivieri JF, Hynes JT, Laage D. Water dynamics and sum-frequency generation spectra at electrode/aqueous electrolyte interfaces. Faraday Discuss 2024; 249:289-302. [PMID: 37791579 DOI: 10.1039/d3fd00103b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
The dynamics of water at interfaces between an electrode and an electrolyte is essential for the transport of redox species and for the kinetics of charge transfer reactions next to the electrode. However, while the effects of electrode potential and ion concentration on the electric double layer structure have been extensively studied, a comparable understanding of dynamical aspects is missing. Interfacial water dynamics presents challenges since it is expected to result from the complex combination of water-water, water-electrode and water-ion interactions. Here we perform molecular dynamics simulations of aqueous NaCl solutions at the interface with graphene electrodes, and examine the impact of both ion concentration and electrode potential on interfacial water reorientational dynamics. We show that for all salt concentrations water dynamics exhibits strongly asymmetric behavior: it slows down at increasingly positively charged electrodes but it accelerates at increasingly negatively charged electrodes. At negative potentials water dynamics is determined mostly by the electrode potential value, but in contrast at positive potentials it is governed both by ion-water and electrode-water interactions. We show how these strikingly different behaviors are determined by the interfacial hydrogen-bond network structure and by the ions' surface affinity. Finally, we indicate how the structural rearrangements impacting water dynamics can be probed via vibrational sum-frequency generation spectroscopy.
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Affiliation(s)
- Jean-François Olivieri
- PASTEUR, Department of Chemistry, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France.
| | - James T Hynes
- PASTEUR, Department of Chemistry, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France.
- Department of Chemistry, University of Colorado, Boulder, Colorado 80309, USA
| | - Damien Laage
- PASTEUR, Department of Chemistry, École normale supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France.
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7
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Becker M, Loche P, Rezaei M, Wolde-Kidan A, Uematsu Y, Netz RR, Bonthuis DJ. Multiscale Modeling of Aqueous Electric Double Layers. Chem Rev 2024; 124:1-26. [PMID: 38118062 PMCID: PMC10785765 DOI: 10.1021/acs.chemrev.3c00307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2023] [Revised: 11/17/2023] [Accepted: 11/30/2023] [Indexed: 12/22/2023]
Abstract
From the stability of colloidal suspensions to the charging of electrodes, electric double layers play a pivotal role in aqueous systems. The interactions between interfaces, water molecules, ions and other solutes making up the electrical double layer span length scales from Ångströms to micrometers and are notoriously complex. Therefore, explaining experimental observations in terms of the double layer's molecular structure has been a long-standing challenge in physical chemistry, yet recent advances in simulations techniques and computational power have led to tremendous progress. In particular, the past decades have seen the development of a multiscale theoretical framework based on the combination of quantum density functional theory, force-field based simulations and continuum theory. In this Review, we discuss these theoretical developments and make quantitative comparisons to experimental results from, among other techniques, sum-frequency generation, atomic-force microscopy, and electrokinetics. Starting from the vapor/water interface, we treat a range of qualitatively different types of surfaces, varying from soft to solid, from hydrophilic to hydrophobic, and from charged to uncharged.
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Affiliation(s)
| | - Philip Loche
- Fachbereich
Physik, Freie Universität Berlin, 14195 Berlin, Germany
- Laboratory
of Computational Science and Modeling, IMX, École Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Majid Rezaei
- Fachbereich
Physik, Freie Universität Berlin, 14195 Berlin, Germany
- Institute
of Theoretical Chemistry, Ulm University, 89081 Ulm, Germany
| | | | - Yuki Uematsu
- Department
of Physics and Information Technology, Kyushu
Institute of Technology, 820-8502 Iizuka, Japan
- PRESTO,
Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Roland R. Netz
- Fachbereich
Physik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Douwe Jan Bonthuis
- Institute
of Theoretical and Computational Physics, Graz University of Technology, 8010 Graz, Austria
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8
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Tan J, Wang M, Zhang J, Ye S. Determination of the Thickness of Interfacial Water by Time-Resolved Sum-Frequency Generation Vibrational Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:18573-18580. [PMID: 38051545 DOI: 10.1021/acs.langmuir.3c02906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
The physics and chemistry of a charged interface are governed by the structure of the electrical double layer (EDL). Determination of the interfacial water thickness (diw) of the charged interface is crucial to quantitatively describe the EDL structure, but it can be utilized with very scarce experimental methods. Here, we propose and verify that the vibrational relaxation time (T1) of the OH stretching mode at 3200 cm-1, obtained by time-resolved sum frequency generation vibrational spectroscopy with ssp polarizations, provides an effective tool to determine diw. By investigating the T1 values at the SiO2/NaCl solution interface, we established a time-space (T1-diw) relationship. We find that water has a T1 lifetime of ≥0.5 ps for diw ≤ 3 Å, while it displays bulk-like dynamics with T1 ≤ 0.2 ps for diw ≥ 9 Å. T1 decreases as diw increases from ∼3 Å to 9 Å. The hydration water at the DPPG lipid bilayer and LK15β protein interfaces has a thickness of ≥9 Å and shows a bulk-like feature. The time-space relationship will provide a novel tool to pattern the interfacial topography and heterogeneity in Ångstrom-depth resolution by imaging the T1 values.
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Affiliation(s)
- Junjun Tan
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
| | - Mengmeng Wang
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Jiahui Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
| | - Shuji Ye
- Hefei National Research Center for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, Anhui 230088, China
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9
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Peng L, Hsu CC, Xiao C, Bonn D, Weber B. Controlling Macroscopic Friction through Interfacial Siloxane Bonding. PHYSICAL REVIEW LETTERS 2023; 131:226201. [PMID: 38101386 DOI: 10.1103/physrevlett.131.226201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 10/12/2023] [Indexed: 12/17/2023]
Abstract
Controlling macroscopic friction is crucial for numerous natural and industrial applications, ranging from forecasting earthquakes to miniaturizing semiconductor devices, but predicting and manipulating friction phenomena remains a challenge due to the unknown relationship between nanoscale and macroscopic friction. Here, we show experimentally that dry friction at multiasperity Si-on-Si interfaces is dominated by the formation of interfacial siloxane (Si─O─Si) bonds, the density of which can be precisely regulated by exposing plasma-cleaned silicon surfaces to dry nitrogen. Our results show how the bond density can be used to quantitatively understand and control the macroscopic friction. Our findings establish a unique connection between the molecular scale at which adhesion occurs, and the friction coefficient that is the key macroscopic parameter for industrial and natural tribology challenges.
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Affiliation(s)
- Liang Peng
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Chao-Chun Hsu
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
| | - Chen Xiao
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
- Advanced Research Center for Nanolithography (ARCNL), Science Park 106, 1098 XG Amsterdam, The Netherlands
| | - Daniel Bonn
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Bart Weber
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
- Advanced Research Center for Nanolithography (ARCNL), Science Park 106, 1098 XG Amsterdam, The Netherlands
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10
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Siretanu I, van Lin SR, Mugele F. Ion adsorption and hydration forces: a comparison of crystalline mica vs. amorphous silica surfaces. Faraday Discuss 2023; 246:274-295. [PMID: 37408390 PMCID: PMC10568262 DOI: 10.1039/d3fd00049d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 03/13/2023] [Indexed: 10/13/2023]
Abstract
Hydration forces are ubiquitous in nature and technology. Yet, the characterization of interfacial hydration structures and their dependence on the nature of the substrate and the presence of ions have remained challenging and controversial. We present a systematic study using dynamic Atomic Force Microscopy of hydration forces on mica surfaces and amorphous silica surfaces in aqueous electrolytes containing chloride salts of various alkali and earth alkaline cations of variable concentrations at pH values between 3 and 9. Our measurements with ultra-sharp AFM tips demonstrate the presence of both oscillatory and monotonically decaying hydration forces of very similar strength on both atomically smooth mica and amorphous silica surfaces with a roughness comparable to the size of a water molecule. The characteristic range of the forces is approximately 1 nm, independent of the fluid composition. Force oscillations are consistent with the size of water molecules for all conditions investigated. Weakly hydrated Cs+ ions are the only exception: they disrupt the oscillatory hydration structure and induce attractive monotonic hydration forces. On silica, force oscillations are also smeared out if the size of the AFM tip exceeds the characteristic lateral scale of the surface roughness. The observation of attractive monotonic hydration forces for asymmetric systems suggests opportunities to probe water polarization.
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Affiliation(s)
- Igor Siretanu
- Physics of Complex Fluids Group and MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - Simone R van Lin
- Physics of Complex Fluids Group and MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
| | - Frieder Mugele
- Physics of Complex Fluids Group and MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
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11
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Wan L, Lu L, Liang X, Liu Z, Huang X, Du R, Luo Q, Xu Q, Zhang Q, Jia X. Citrate-Based Polyester Elastomer with Artificially Regulatable Degradation Rate on Demand. Biomacromolecules 2023; 24:4123-4137. [PMID: 37584644 DOI: 10.1021/acs.biomac.3c00479] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
Citrate-based polymers are commonly used to create biodegradable implants. In an era of personalized medicine, it is highly desired that the degradation rates of citrate-based implants can be artificially regulated as required during clinical applications. Unfortunately, current citrate-based polymers only undergo passive degradation, which follows a specific degradation profile. This presents a considerable challenge for the use of citrate-based implants. To address this, a novel citrate-based polyester elastomer (POCSS) with artificially regulatable degradation rate is developed by incorporating disulfide bonds (S-S) into the backbone chains of the crosslinking network of poly(octamethylene citrate) (POC). This POCSS exhibits excellent and tunable mechanical properties, notable antibacterial properties, good biocompatibility, and low biotoxicity of its degradation products. The degradation rate of the POCSS can be regulated by breaking the S-S in its crosslinking network using glutathione (GSH). After a period of subcutaneous implantation of POCSS scaffolds in mice, the degradation rate eventually increased by 2.46 times through the subcutaneous administration of GSH. Notably, we observed no significant adverse effects on its surrounding tissues, the balance of the physiological environment, major organs, and the health status of the mice during degradation.
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Affiliation(s)
- Lu Wan
- Key Laboratory of High Performance Polymer Material and Technology of MOE, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Liangliang Lu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing 210023, P. R. China
| | - Xuejiao Liang
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing 210023, P. R. China
| | - Zhichang Liu
- Kuang Yaming Honors School, Nanjing University, Nanjing 210023, P. R. China
| | - Xinxin Huang
- Key Laboratory of High Performance Polymer Material and Technology of MOE, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Ruichun Du
- Key Laboratory of High Performance Polymer Material and Technology of MOE, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Qiong Luo
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing 210023, P. R. China
| | - Qiang Xu
- State Key Laboratory of Pharmaceutical Biotechnology, Department of Biotechnology and Pharmaceutical Sciences, School of Life Sciences, Nanjing University, Nanjing 210023, P. R. China
| | - Qiuhong Zhang
- Key Laboratory of High Performance Polymer Material and Technology of MOE, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
| | - Xudong Jia
- Key Laboratory of High Performance Polymer Material and Technology of MOE, Department of Polymer Science and Engineering, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, P. R. China
- State Key Laboratory of Coordination Chemistry, Nanjing University, Nanjing 210023, P. R. China
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12
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Ohkubo T, Komiyama N, Masu H, Kishikawa K, Kohri M. Molecular Dynamics Studies of the Ho(III) Aqua-tris(dibenzoylmethane) Complex: Role of Water Dynamics. Inorg Chem 2023. [PMID: 37470095 DOI: 10.1021/acs.inorgchem.3c01277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
The seven-coordinate Ho(III) aqua-tris(dibenzoylmethane)(DBM) complex, referred to as Ho-(DBM)3·H2O, was first reported in the late 1960s. It has a threefold symmetric structure, with Ho at the center of three dibenzoylmethane ligands and hydrogen-bonded water to ligands. It is considered that the hydrogen bonds between the water molecule and the ligands surrounding Ho play an important role in the formation of its symmetrical structure. In this work, we developed new force-field parameters for classical molecular dynamics (CMD) simulations to theoretically elucidate the structure and dynamics of Ho-(DBM)3·H2O. To develop the force field, structural optimization and molecular dynamics were performed on the basis of ab initio calculations using the plane-wave pseudopotential method. The force-field parameters for CMD were then optimized to reproduce the data obtained from ab initio calculations. Validation of the developed force field showed good agreement with the experimental crystalline structure and ab initio data. The vibrational properties of water in Ho-(DBM)3·H2O were investigated by comparison with bulk liquid water. The vibrational motion of water was found to have a characteristic mode originating from stationary rotational motion along the c-axis of Ho(III) aqua-tris(dibenzoylmethane). Contrary to expectations, the hydrogen-bond dynamics of water in Ho-(DBM)3·H2O were found to be almost equivalent to those of bulk liquid water except for librational motion. This development route for force-field parameters for CMD and the establishment of water dynamics can advance the understanding of water-coordinated metal complexes with high coordination numbers such as Ho-(DBM)3·H2O.
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Affiliation(s)
- Takahiro Ohkubo
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho Inage-ku, Chiba 263-8522, Japan
| | - Nao Komiyama
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho Inage-ku, Chiba 263-8522, Japan
| | - Hyuma Masu
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho Inage-ku, Chiba 263-8522, Japan
| | - Keiki Kishikawa
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho Inage-ku, Chiba 263-8522, Japan
| | - Michinari Kohri
- Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho Inage-ku, Chiba 263-8522, Japan
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13
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Beckwée EJ, Watson G, Houlleberghs M, Arenas Esteban D, Bals S, Van Der Voort P, Breynaert E, Martens J, Baron GV, Denayer JF. Enabling hydrate-based methane storage under mild operating conditions by periodic mesoporous organosilica nanotubes. Heliyon 2023; 9:e17662. [PMID: 37449178 PMCID: PMC10336592 DOI: 10.1016/j.heliyon.2023.e17662] [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: 05/31/2023] [Revised: 06/14/2023] [Accepted: 06/25/2023] [Indexed: 07/18/2023] Open
Abstract
Biomethane is a renewable natural gas substitute produced from biogas. Storage of this sustainable energy vector in confined clathrate hydrates, encapsulated in the pores of a host material, is a highly promising avenue to improve storage capacity and energy efficiency. Herein, a new type of periodic mesoporous organosilica (PMO) nanotubes, referred to as hollow ring PMO (HR-PMO), capable of promoting methane clathrate hydrate formation under mild working conditions (273 K, 3.5 MPa) and at high water loading (5.1 g water/g HR-PMO) is reported. Gravimetric uptake measurements reveal a steep single-stepped isotherm and a noticeably high methane storage capacity (0.55 g methane/g HR-PMO; 0.11 g methane/g water at 3.5 MPa). The large working capacity throughout consecutive pressure-induced clathrate hydrate formation-dissociation cycles demonstrates the material's excellent recyclability (97% preservation of capacity). Supported by ex situ cryo-electron tomography and x-ray diffraction, HR-PMO nanotubes are hypothesized to promote clathrate hydrate nucleation and growth by distribution and confinement of water in the mesopores of their outer wall, along the central channels of the nanotubes and on the external nanotube surface. These findings showcase the potential for application of organosilica materials with hierarchical and interconnected pore systems for pressure-based storage of biomethane in confined clathrate hydrates.
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Affiliation(s)
- Emile Jules Beckwée
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussel, Belgium
| | - Geert Watson
- Center for Ordered Materials, Organometallics and Catalysis, Department of Chemistry, Ghent University, Krijgslaan 281, B-9000, Ghent, Belgium
| | - Maarten Houlleberghs
- Centre for Surface Chemistry and Catalysis, NMRCoRe - NMR - XRAY - EM Platform for Convergence Research, Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Daniel Arenas Esteban
- Electron Microscopy for Materials Science, Department of Physics, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
| | - Sara Bals
- Electron Microscopy for Materials Science, Department of Physics, University of Antwerp, Groenenborgerlaan 171, 2020, Antwerp, Belgium
| | - Pascal Van Der Voort
- Center for Ordered Materials, Organometallics and Catalysis, Department of Chemistry, Ghent University, Krijgslaan 281, B-9000, Ghent, Belgium
| | - Eric Breynaert
- Centre for Surface Chemistry and Catalysis, NMRCoRe - NMR - XRAY - EM Platform for Convergence Research, Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Johan Martens
- Centre for Surface Chemistry and Catalysis, NMRCoRe - NMR - XRAY - EM Platform for Convergence Research, Department of Microbial and Molecular Systems (M2S), KU Leuven, Celestijnenlaan 200F, 3001, Leuven, Belgium
| | - Gino V. Baron
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussel, Belgium
| | - Joeri F.M. Denayer
- Department of Chemical Engineering, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussel, Belgium
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14
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Raji F, Nguyen CV, Nguyen NN, Nguyen TAH, Nguyen AV. Probing interfacial water structure induced by charge reversal and hydrophobicity of silica surface in the presence of divalent heavy metal ions using sum frequency generation spectroscopy. J Colloid Interface Sci 2023; 647:152-162. [PMID: 37247479 DOI: 10.1016/j.jcis.2023.05.125] [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: 05/13/2022] [Revised: 05/12/2023] [Accepted: 05/17/2023] [Indexed: 05/31/2023]
Abstract
HYPOTHESIS Adsorption of divalent heavy metal ions (DHMIs) at the mineral-water interfaces changes interfacial chemical species and charges, interfacial water structure, Stern (SL), and diffuse (DL) layers. These molecular changes can be detected by probing changing orientation and hydrogen-bond network of interfacial water molecules in response to changing local charges and hydrophobicity. EXPERIMENTS Sum-frequency generation (SFG) spectroscopy was used to probe changes in vibrational resonances of interfacial OH vs. DHMI concentration and pH. SFG spectra were deconvoluted using the measured surface potential and maximum entropy method in conjunction with the electrical double-layer theory for the SL and DL structures and correlated by hydrophobicity. FINDINGS Three surface charge reversals (CRs) were detected at low (CR1), medium (CR2), and high (CR3) pHs. Unlike CR1, SFG signals were minimized at CR2 and CR3 for DHMIs-silica systems highlighting considerable alterations in the structure of interfacial waters due to the inner-sphere sorption of metal hydroxo complexes. SFG results showed "hydrophobic-like" stretching modes at > 3600 cm-1 for Pb-, Cu-, and Zn-treated silica. However, contact angle measurements revealed the hydrophobization of silica only in the presence of Pb(II), as confirmed by an in-depth SFG analysis of the hydrogen-bond network of the interfacial water molecules in the SL.
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Affiliation(s)
- Foad Raji
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Cuong V Nguyen
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Ngoc N Nguyen
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Tuan A H Nguyen
- Sustainable Minerals Institute, The University of Queensland, QLD 4072, Australia
| | - Anh V Nguyen
- School of Chemical Engineering, The University of Queensland, Brisbane, Queensland 4072, Australia.
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15
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Bañuelos JL, Borguet E, Brown GE, Cygan RT, DeYoreo JJ, Dove PM, Gaigeot MP, Geiger FM, Gibbs JM, Grassian VH, Ilgen AG, Jun YS, Kabengi N, Katz L, Kubicki JD, Lützenkirchen J, Putnis CV, Remsing RC, Rosso KM, Rother G, Sulpizi M, Villalobos M, Zhang H. Oxide- and Silicate-Water Interfaces and Their Roles in Technology and the Environment. Chem Rev 2023; 123:6413-6544. [PMID: 37186959 DOI: 10.1021/acs.chemrev.2c00130] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Interfacial reactions drive all elemental cycling on Earth and play pivotal roles in human activities such as agriculture, water purification, energy production and storage, environmental contaminant remediation, and nuclear waste repository management. The onset of the 21st century marked the beginning of a more detailed understanding of mineral aqueous interfaces enabled by advances in techniques that use tunable high-flux focused ultrafast laser and X-ray sources to provide near-atomic measurement resolution, as well as by nanofabrication approaches that enable transmission electron microscopy in a liquid cell. This leap into atomic- and nanometer-scale measurements has uncovered scale-dependent phenomena whose reaction thermodynamics, kinetics, and pathways deviate from previous observations made on larger systems. A second key advance is new experimental evidence for what scientists hypothesized but could not test previously, namely, interfacial chemical reactions are frequently driven by "anomalies" or "non-idealities" such as defects, nanoconfinement, and other nontypical chemical structures. Third, progress in computational chemistry has yielded new insights that allow a move beyond simple schematics, leading to a molecular model of these complex interfaces. In combination with surface-sensitive measurements, we have gained knowledge of the interfacial structure and dynamics, including the underlying solid surface and the immediately adjacent water and aqueous ions, enabling a better definition of what constitutes the oxide- and silicate-water interfaces. This critical review discusses how science progresses from understanding ideal solid-water interfaces to more realistic systems, focusing on accomplishments in the last 20 years and identifying challenges and future opportunities for the community to address. We anticipate that the next 20 years will focus on understanding and predicting dynamic transient and reactive structures over greater spatial and temporal ranges as well as systems of greater structural and chemical complexity. Closer collaborations of theoretical and experimental experts across disciplines will continue to be critical to achieving this great aspiration.
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Affiliation(s)
- José Leobardo Bañuelos
- Department of Physics, The University of Texas at El Paso, El Paso, Texas 79968, United States
| | - Eric Borguet
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Gordon E Brown
- Department of Earth and Planetary Sciences, The Stanford Doerr School of Sustainability, Stanford University, Stanford, California 94305, United States
| | - Randall T Cygan
- Department of Soil and Crop Sciences, Texas A&M University, College Station, Texas 77843, United States
| | - James J DeYoreo
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Patricia M Dove
- Department of Geosciences, Department of Chemistry, Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Marie-Pierre Gaigeot
- Université Paris-Saclay, Univ Evry, CNRS, LAMBE UMR8587, 91025 Evry-Courcouronnes, France
| | - Franz M Geiger
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Julianne M Gibbs
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2Canada
| | - Vicki H Grassian
- Department of Chemistry and Biochemistry, University of California, San Diego, California 92093, United States
| | - Anastasia G Ilgen
- Geochemistry Department, Sandia National Laboratories, Albuquerque, New Mexico 87185, United States
| | - Young-Shin Jun
- Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, United States
| | - Nadine Kabengi
- Department of Geosciences, Georgia State University, Atlanta, Georgia 30303, United States
| | - Lynn Katz
- Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, Texas 78712, United States
| | - James D Kubicki
- Department of Earth, Environmental & Resource Sciences, The University of Texas at El Paso, El Paso, Texas 79968, United States
| | - Johannes Lützenkirchen
- Karlsruher Institut für Technologie (KIT), Institut für Nukleare Entsorgung─INE, Eggenstein-Leopoldshafen 76344, Germany
| | - Christine V Putnis
- Institute for Mineralogy, University of Münster, Münster D-48149, Germany
| | - Richard C Remsing
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, United States
| | - Kevin M Rosso
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Gernot Rother
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Marialore Sulpizi
- Department of Physics, Ruhr Universität Bochum, NB6, 65, 44780, Bochum, Germany
| | - Mario Villalobos
- Departamento de Ciencias Ambientales y del Suelo, LANGEM, Instituto De Geología, Universidad Nacional Autónoma de México, Mexico City 04510, Mexico
| | - Huichun Zhang
- Department of Civil and Environmental Engineering, Case Western Reserve University, Cleveland, Ohio 44106, United States
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16
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Wei F, Urashima SH, Nihonyanagi S, Tahara T. Elucidation of the pH-Dependent Electric Double Layer Structure at the Silica/Water Interface Using Heterodyne-Detected Vibrational Sum Frequency Generation Spectroscopy. J Am Chem Soc 2023; 145:8833-8846. [PMID: 37068781 PMCID: PMC10143621 DOI: 10.1021/jacs.2c11344] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Indexed: 04/19/2023]
Abstract
The silica/water interface is one of the most abundant charged interfaces in natural environments, and the elucidation of the water structure at the silica/water interface is essential. In the present study, we measured the interface-selective vibrational (χ(2)) spectra in the OH stretch region of the silica/water interface in a wide pH range of pH 2.0-12.0 while changing the salt concentration by heterodyne-detected vibrational sum-frequency generation spectroscopy. With the help of singular value decomposition analysis, it is shown that the imaginary part of the χ(2) (Imχ(2)) spectra can be decomposed into the spectra of the diffuse Gouy-Chapman layer (DL) and the compact Stern layer (SL), which enables us to quantitatively analyze the spectra of DL and SL separately. The salt-concentration dependence of the DL spectra at different pH values is analyzed using the modified Gouy-Chapman theory, and the pH-dependent surface charge density and the pKa value (4.8 ± 0.2) of the silica/water interface are evaluated. Furthermore, it is found that the pH-dependent change of the SL spectra is quantitatively explained by three spectral components that represent the three characteristic water species appearing in different pH regions in SL. The quantitative understanding obtained from the analysis of each spectral component in the Imχ(2) spectra provides a clear molecular-level picture of the electric double layer at the silica/water interface.
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Affiliation(s)
- Feng Wei
- Molecular
Spectroscopy Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Shu-hei Urashima
- Molecular
Spectroscopy Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
| | - Satoshi Nihonyanagi
- Molecular
Spectroscopy Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
- Ultrafast
Spectroscopy Research Team, RIKEN Center
for Advanced Photonics (RAP), Wako, Saitama 351-0198, Japan
| | - Tahei Tahara
- Molecular
Spectroscopy Laboratory, RIKEN, Wako, Saitama 351-0198, Japan
- Ultrafast
Spectroscopy Research Team, RIKEN Center
for Advanced Photonics (RAP), Wako, Saitama 351-0198, Japan
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17
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Pezzotti S, König B, Ramos S, Schwaab G, Havenith M. Liquid-Liquid Phase Separation? Ask the Water! J Phys Chem Lett 2023; 14:1556-1563. [PMID: 36745512 DOI: 10.1021/acs.jpclett.2c02697] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Water is more than an inert spectator during liquid-liquid phase separation (LLPS), the reversible compartmentalization of protein solutions into a protein-rich and a dilute phase. We show that LLPS is driven by changes in hydration entropy and enthalpy. Tuning LLPS by adjusting experimental parameters, e.g., addition of co-solutes, is a major goal for biological and medical applications. This requires a general model to quantify thermodynamic driving forces. Here, we develop such a model based on the measured amplitudes of characteristic THz-features of two hydration populations: "Cavity-wrap" water hydrating hydrophobic patches is released during LLPS leading to an increase in entropy. "Bound" water hydrating hydrophilic patches is retained since it is enthalpically favorable. We introduce a THz-phase diagram mapping these spectroscopic/thermodynamic changes. This provides not only a precise understanding of hydrophobic and hydrophilic hydration driving forces as a function of temperature and concentration but also a rational means to tune LLPS.
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Affiliation(s)
- Simone Pezzotti
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Benedikt König
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Sashary Ramos
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Gerhard Schwaab
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
| | - Martina Havenith
- Department of Physical Chemistry II, Ruhr University Bochum, 44801Bochum, Germany
- Department of Physics, Technische Universität Dortmund, 44227Dortmund, Germany
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18
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Zhang H, Sun W, Chen D, Lin S, Zhang C. Effects of Interfacial Hydroxylation Microstructure on Quartz Flotation by Sodium Oleate. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:2182-2191. [PMID: 36716219 DOI: 10.1021/acs.langmuir.2c02651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Quartz, a common inorganic nonmetallic mineral, is usually removed or purified by beneficiation, normally flotation. Given the strong polarity of the quartz surface, it is easy to hydrate to form a hydroxylation layer, which makes it impossible to float quartz with sodium oleate (OL) used alone. An ideal flotation method for quartz is preactivation with Ca2+, followed by collection with OL. Herein, the effects of surface hydroxylation on the adsorption of the anionic collector OL on the quartz surface before and after Ca2+ activation are systematically investigated by density functional theory (DFT) calculations. The results show that the displacement adsorption of surface hydroxyl substituted by OL- is not feasible in thermodynamics, and the OL- can only bind to the H atoms of the hydroxylated quartz surface via hydrogen bonds, namely, hydrogen binding adsorption. Due to the electrostatic repulsion and steric hindrance effect induced by the surface hydroxylation structure, the adsorption ability of OL- on the quartz surface mediated by hydroxyl bridges is very weak, which is insufficient to realize quartz floating. However, Ca2+ ions are easily adsorbed on the hydroxylated quartz surface, providing favorable active sites for subsequent adsorption of OL-, thus becoming a credible solution for the industrial flotation of the strong hydrophilic mineral quartz. These findings shed some new insights for accurately understanding the flotation mechanism of strongly hydrophilic oxide minerals and are beneficial to promoting the development of mineral flotation fundamentals.
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Affiliation(s)
- Hongliang Zhang
- School of Minerals Processing and Bioengineering, Central South University, Changsha410083, China
| | - Wei Sun
- School of Minerals Processing and Bioengineering, Central South University, Changsha410083, China
| | - Daixiong Chen
- Hunan Provincial Key Laboratory of Complex Copper Lead Zinc Associated Metal Resources Comprehensive Utilization, Hunan Research Institute for Nonferrous Metals, Changsha410100, China
| | - Shangyong Lin
- School of Minerals Processing and Bioengineering, Central South University, Changsha410083, China
| | - Chenyang Zhang
- School of Minerals Processing and Bioengineering, Central South University, Changsha410083, China
- Hunan Provincial Key Laboratory of Complex Copper Lead Zinc Associated Metal Resources Comprehensive Utilization, Hunan Research Institute for Nonferrous Metals, Changsha410100, China
- State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming650093, China
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19
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Chen W, Sanders SE, Özdamar B, Louaas D, Brigiano FS, Pezzotti S, Petersen PB, Gaigeot MP. On the Trail of Molecular Hydrophilicity and Hydrophobicity at Aqueous Interfaces. J Phys Chem Lett 2023; 14:1301-1309. [PMID: 36724059 DOI: 10.1021/acs.jpclett.2c03300] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Uncovering microscopic hydrophilicity and hydrophobicity at heterogeneous aqueous interfaces is essential as it dictates physico/chemical properties such as wetting, the electrical double layer, and reactivity. Several molecular and spectroscopic descriptors were proposed, but a major limitation is the lack of connections between them. Here, we combine density functional theory-based MD simulations (DFT-MD) and SFG spectroscopy to explore how interfacial water responds in contact with self-assembled monolayers (SAM) of tunable hydrophilicity. We introduce a microscopic metric to track the transition from hydrophobic to hydrophilic interfaces. This metric combines the H/V descriptor, a structural descriptor based on the preferential orientation within the water network in the topmost binding interfacial layer (BIL) and spectroscopic fingerprints of H-bonded and dangling OH groups of water carried by BIL-resolved SFG spectra. This metric builds a bridge between molecular descriptors of hydrophilicity/hydrophobicity and spectroscopically measured quantities and provides a recipe to quantitatively or qualitatively interpret experimental SFG signals.
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Affiliation(s)
- Wanlin Chen
- Université Paris-Saclay, Université Evry, CNRS, LAMBE UMR8587, 91025Evry-Courcouronnes, France
| | - Stephanie E Sanders
- Department of Chemistry and Biochemistry, Ruhr University Bochum, 44801Bochum, Germany
| | - Burak Özdamar
- Université Paris-Saclay, Université Evry, CNRS, LAMBE UMR8587, 91025Evry-Courcouronnes, France
| | - Dorian Louaas
- Université Paris-Saclay, Université Evry, CNRS, LAMBE UMR8587, 91025Evry-Courcouronnes, France
| | - Flavio Siro Brigiano
- Université Paris-Saclay, Université Evry, CNRS, LAMBE UMR8587, 91025Evry-Courcouronnes, France
- Laboratoire de Chimie Théorique, Sorbonne Université, UMR 7616 CNRS, 4 Place Jussieu, 75005Paris, France
| | - Simone Pezzotti
- Université Paris-Saclay, Université Evry, CNRS, LAMBE UMR8587, 91025Evry-Courcouronnes, France
- Department of Physical Chemistry II, Ruhr University Bochum, D-44801Bochum, Germany
| | - Poul B Petersen
- Department of Chemistry and Biochemistry, Ruhr University Bochum, 44801Bochum, Germany
| | - Marie-Pierre Gaigeot
- Université Paris-Saclay, Université Evry, CNRS, LAMBE UMR8587, 91025Evry-Courcouronnes, France
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20
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Dallin BC, Kelkar AS, Van Lehn RC. Structural features of interfacial water predict the hydrophobicity of chemically heterogeneous surfaces. Chem Sci 2023; 14:1308-1319. [PMID: 36756335 PMCID: PMC9891380 DOI: 10.1039/d2sc02856e] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 01/02/2023] [Indexed: 01/04/2023] Open
Abstract
The hydrophobicity of an interface determines the magnitude of hydrophobic interactions that drive numerous biological and industrial processes. Chemically heterogeneous interfaces are abundant in these contexts; examples include the surfaces of proteins, functionalized nanomaterials, and polymeric materials. While the hydrophobicity of nonpolar solutes can be predicted and related to the structure of interfacial water molecules, predicting the hydrophobicity of chemically heterogeneous interfaces remains a challenge because of the complex, non-additive contributions to hydrophobicity that depend on the chemical identity and nanoscale spatial arrangements of polar and nonpolar groups. In this work, we utilize atomistic molecular dynamics simulations in conjunction with enhanced sampling and data-centric analysis techniques to quantitatively relate changes in interfacial water structure to the hydration free energy (a thermodynamically well-defined descriptor of hydrophobicity) of chemically heterogeneous interfaces. We analyze a large data set of 58 self-assembled monolayers (SAMs) composed of ligands with nonpolar and polar end groups of different chemical identity (amine, amide, and hydroxyl) in five mole fractions, two spatial patterns, and with scaled partial charges. We find that only five features of interfacial water structure are required to accurately predict hydration free energies. Examination of these features reveals mechanistic insights into the interfacial hydrogen bonding behaviors that distinguish different surface compositions and patterns. This analysis also identifies the probability of highly coordinated water structures as a unique signature of hydrophobicity. These insights provide a physical basis to understand the hydrophobicity of chemically heterogeneous interfaces and connect hydrophobicity to experimentally accessible perturbations of interfacial water structure.
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Affiliation(s)
- Bradley C. Dallin
- Department of Chemical and Biological Engineering, University of Wisconsin – Madison1415 Engineering DriveMadisonWI53706USA+1-608-263-9487
| | - Atharva S. Kelkar
- Department of Chemical and Biological Engineering, University of Wisconsin – Madison1415 Engineering DriveMadisonWI53706USA+1-608-263-9487
| | - Reid C. Van Lehn
- Department of Chemical and Biological Engineering, University of Wisconsin – Madison1415 Engineering DriveMadisonWI53706USA+1-608-263-9487
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21
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El Samrout O, Berlier G, Lambert JF, Martra G. Polypeptide Chain Growth Mechanisms and Secondary Structure Formation in Glycine Gas-Phase Deposition on Silica Surfaces. J Phys Chem B 2023; 127:673-684. [PMID: 36637235 PMCID: PMC9884078 DOI: 10.1021/acs.jpcb.2c07382] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Peptide formation by amino acids condensation represents a crucial reaction in the quest of the origins of life as well as in synthetic chemistry. However, it is still poorly understood in terms of efficiency and reaction mechanism. In the present work, peptide formation has been investigated through thermal condensation of gas-phase glycine in fluctuating silica environments as a model of prebiotic environments. In-situ IR spectroscopy measurements under a controlled atmosphere reveal that a humidity fluctuating system subjected to both temperature and water activity variations results in the formation of more abundant peptides compared to a dehydrated system subjected only to temperature fluctuations cycles. A model is proposed in which hydration steps result in the hydrolysis and redistribution of the oligomers formed during previous deposition in dry conditions. This results in the formation of self-assembled aggregates with well-defined secondary structures (especially β-sheets). Upon further monomers feeding, structural elements are conserved in newly growing chains, with indications of templated polymerization. The structural dynamics of peptides were also evaluated. Rigid self-assembled structures with a high resistance to further wetting/drying cycles and inaccessibility to isotopic exchange were present in the humidity fluctuating system compared to more flexible structures in the dehydrated system. The resistance and growth of self-assembled structures were also investigated for an extended duration of Gly deposition using isotope labeling.
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Affiliation(s)
- Ola El Samrout
- Department
of Chemistry and NIS Centre, University
of Torino, Via P. Giuria 7, 10125Torino, Italy,Laboratoire
de Réactivité de Surface, LRS (UMR 7197 CNRS), Sorbonne Université, Place Jussieu, 75005Paris, France
| | - Gloria Berlier
- Department
of Chemistry and NIS Centre, University
of Torino, Via P. Giuria 7, 10125Torino, Italy,
| | - Jean-François Lambert
- Laboratoire
de Réactivité de Surface, LRS (UMR 7197 CNRS), Sorbonne Université, Place Jussieu, 75005Paris, France,
| | - Gianmario Martra
- Department
of Chemistry and NIS Centre, University
of Torino, Via P. Giuria 7, 10125Torino, Italy
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22
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Piontek S, Naujoks D, Tabassum T, DelloStritto MJ, Jaugstetter M, Hosseini P, Corva M, Ludwig A, Tschulik K, Klein ML, Petersen PB. Probing the Gold/Water Interface with Surface-Specific Spectroscopy. ACS PHYSICAL CHEMISTRY AU 2023; 3:119-129. [PMID: 36718265 PMCID: PMC9881240 DOI: 10.1021/acsphyschemau.2c00044] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 12/08/2022] [Accepted: 12/08/2022] [Indexed: 01/05/2023]
Abstract
Water is an integral component in electrochemistry, in the generation of the electric double layer, and in the propagation of the interfacial electric fields into the solution; however, probing the molecular-level structure of interfacial water near functioning electrode surfaces remains challenging. Due to the surface-specificity, sum-frequency-generation (SFG) spectroscopy offers an opportunity to investigate the structure of water near working electrochemical interfaces but probing the hydrogen-bonded structure of water at this buried electrode-electrolyte interface was thought to be impossible. Propagating the laser beams through the solvent leads to a large attenuation of the infrared light due to the absorption of water, and interrogating the interface by sending the laser beams through the electrode normally obscures the SFG spectra due to the large nonlinear response of conduction band electrons. Here, we show that the latter limitation is removed when the gold layer is thin. To demonstrate this, we prepared Au gradient films on CaF2 with a thickness between 0 and 8 nm. SFG spectra of the Au gradient films in contact with H2O and D2O demonstrate that resonant water SFG spectra can be obtained using Au films with a thickness of ∼2 nm or less. The measured spectra are distinctively different from the frequency-dependent Fresnel factors of the interface, suggesting that the features we observe in the OH stretching region indeed do not arise from the nonresonant response of the Au films. With the newfound ability to probe interfacial solvent structure at electrode/aqueous interfaces, we hope to provide insights into more efficient electrolyte composition and electrode design.
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Affiliation(s)
- Stefan
M. Piontek
- Faculty
of Chemistry and Biochemistry, Ruhr-Universität
Bochum, 44801 Bochum, Germany,Light
Conversion Inc., Vilnius City Municipality, Vilnius 10234, Lithuania
| | - Dennis Naujoks
- Faculty
of Mechanical Engineering, Institute for Materials and ZGH, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Tadneem Tabassum
- Faculty
of Chemistry and Biochemistry, Ruhr-Universität
Bochum, 44801 Bochum, Germany
| | - Mark J. DelloStritto
- Institute
for Computational Molecular Science, Temple
University, Philadelphia, 19122 Pennsylvania, United States
| | | | - Pouya Hosseini
- Max-Planck-Institut
für Eisenforschung GmbH, 40237 Düsseldorf, Germany
| | - Manuel Corva
- Faculty
of Chemistry and Biochemistry, Ruhr-Universität
Bochum, 44801 Bochum, Germany
| | - Alfred Ludwig
- Faculty
of Mechanical Engineering, Institute for Materials and ZGH, Ruhr-Universität Bochum, 44801 Bochum, Germany
| | - Kristina Tschulik
- Faculty
of Chemistry and Biochemistry, Ruhr-Universität
Bochum, 44801 Bochum, Germany
| | - Michael L. Klein
- Institute
for Computational Molecular Science, Temple
University, Philadelphia, 19122 Pennsylvania, United States
| | - Poul B. Petersen
- Faculty
of Chemistry and Biochemistry, Ruhr-Universität
Bochum, 44801 Bochum, Germany,
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23
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Rashwan M, Rehl B, Romaniuk N, Gibbs JM. Probing Silica-Kaolinite Interactions with Sum Frequency Generation Spectroscopy. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:15984-15994. [PMID: 36519947 DOI: 10.1021/acs.langmuir.2c02414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
Treating the oil sands tailings ponds is a major challenge because of the vast amounts of tailings and the need for a reliable treatment technique for releasing water and generating the highly consolidated material required for land reclamation. Treatment with chemicals such as lime (calcium (hydr)oxide) is a promising technology for tailings dewatering and consolidation, particularly at higher pH. Given that kaolinite and silica minerals are the main constituents of many oil sands, we have investigated the influence of lime and NaOH addition on the silica/aqueous kaolinite interface over the pH range 7.4-12.4 using vibrational sum frequency generation spectroscopy (SFG). With lime addition, at pH 12.0 and above we observe a complete disappearance of the vibrational features of the interfacial water molecules for planar silica in contact with an aqueous dispersion of kaolinite particles. A concurrent increase in the amount of adsorbed kaolinite on the silica surface at pH 12.0 and above is observed, shown in the increased intensity of the kaolinite SFG peak at 3694 cm-1. This suggests that the absence of water features in the SFG spectra is associated with conditions that facilitate dewatering. With NaOH addition, however, the interfacial water SF intensity is still significant even under highly alkaline conditions despite the increase in adsorbed kaolinite at high pH. To better understand the SFG observations and get a deeper insight into the chemistry of the silica/aqueous kaolinite interface, we measure the ζ-potential on the planar silica/aqueous interface and kaolinite aqueous dispersions under the same pH conditions with NaOH and lime addition.
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Affiliation(s)
- Mokhtar Rashwan
- Department of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2G2, Canada
| | - Benjamin Rehl
- Department of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2G2, Canada
| | - Nikolas Romaniuk
- Graymont Inc. 200-10991, Shelbridge Way, Richmond, British ColumbiaV6X 3C6, Canada
| | - Julianne M Gibbs
- Department of Chemistry, University of Alberta, Edmonton, AlbertaT6G 2G2, Canada
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24
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El Samrout O, Fabbiani M, Berlier G, Lambert JF, Martra G. Emergence of Order in Origin-of-Life Scenarios on Mineral Surfaces: Polyglycine Chains on Silica. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:15516-15525. [PMID: 36469018 PMCID: PMC9776562 DOI: 10.1021/acs.langmuir.2c02106] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 11/21/2022] [Indexed: 06/17/2023]
Abstract
The polymerization of amino acids (AAs) to peptides on oxide surfaces has attracted interest owing to its high importance in biotechnology, prebiotic chemistry, and origin of life theories. However, its mechanism is still poorly understood. We tried to elucidate the reactivity of glycine (Gly) from the vapor phase on the surface of amorphous silica under controlled atmosphere at 160 °C. Infrared (IR) spectroscopy reveals that Gly functionalizes the silica surface through the formation of ester species, which represent, together with the weakly interacting silanols, crucial elements for monomers activation and polymerization. Once activated, β-turns start to form as initiators for the growth of long linear polypeptides (poly-Gly) chains, which elongate into ordered structures containing both β-sheet and helical conformations. The work also points to the role of water vapor in the formation of further self-assembled β-sheet structures that are highly resistant to hydrolysis.
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Affiliation(s)
- Ola El Samrout
- Department
of Chemistry, University of Torino, Via P. Giuria 7, 10125 Torino, Italy
- Laboratoire
de Réactivité de Surface, LRS, Sorbonne Université, Place Jussieu, 75005 Paris, France
| | - Marco Fabbiani
- Department
of Chemistry, University of Torino, Via P. Giuria 7, 10125 Torino, Italy
| | - Gloria Berlier
- Department
of Chemistry, University of Torino, Via P. Giuria 7, 10125 Torino, Italy
| | - Jean-François Lambert
- Laboratoire
de Réactivité de Surface, LRS, Sorbonne Université, Place Jussieu, 75005 Paris, France
| | - Gianmario Martra
- Department
of Chemistry, University of Torino, Via P. Giuria 7, 10125 Torino, Italy
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25
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Vogel P, Möller N, Qaisrani MN, Bista P, Weber SAL, Butt HJ, Liebchen B, Sulpizi M, Palberg T. Charging of Dielectric Surfaces in Contact with Aqueous Electrolytes─the Influence of CO 2. J Am Chem Soc 2022; 144:21080-21087. [DOI: 10.1021/jacs.2c06793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Peter Vogel
- Institute of Physics, Johannes Gutenberg University, 55128Mainz, Germany
| | - Nadir Möller
- Institute of Physics, Johannes Gutenberg University, 55128Mainz, Germany
| | | | - Pravash Bista
- Max Planck Institute for Polymer Research, 55128Mainz, Germany
| | | | | | - Benno Liebchen
- Institute for Condensed Matter Physics, Technische Universität Darmstadt, 64289Darmstadt, Germany
| | - Marialore Sulpizi
- Department of Physics, Ruhr Universität Bochum, 44780Bochum, Germany
| | - Thomas Palberg
- Institute of Physics, Johannes Gutenberg University, 55128Mainz, Germany
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26
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Homogeneous interfacial water structure favors realizing a low-friction coefficient state. J Colloid Interface Sci 2022; 626:324-333. [DOI: 10.1016/j.jcis.2022.06.157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 06/10/2022] [Accepted: 06/27/2022] [Indexed: 11/20/2022]
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27
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Galimberti DR. Vibrational Circular Dichroism from DFT Molecular Dynamics: The AWV Method. J Chem Theory Comput 2022; 18:6217-6230. [PMID: 36112978 PMCID: PMC9558311 DOI: 10.1021/acs.jctc.2c00736] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The paper illustrates the Activity Weighted Velocities
(AWV) methodology
to compute Vibrational Circular Dichroism (VCD) anharmonic spectra
from Density Functional Theory (DFT) molecular dynamics. AWV calculates
the spectra by the Fourier Transform of the time correlation functions
of velocities, weighted by specific observables: the Atomic Polar
Tensors (APTs) and the Atomic Axial Tensors (AATs). Indeed, AWV shows
to correctly reproduce the experimental spectra for systems in the
gas and liquid phases, both in the case of weakly and strongly interacting
systems. The comparison with the experimental spectra is striking
especially in the fingerprint region, as demonstrated by the three
benchmark systems discussed: (1S)-Fenchone in the
gas phase, (S)-(−)-Propylene oxide in the
liquid phase, and (R)-(−)-2-butanol in the
liquid phase. The time evolution of APTs and AATs can be adequately
described by a linear combination of the tensors of a small set of
appropriate reference structures, strongly reducing the computational
cost without compromising accuracy. Additionally, AWV allows the partition
of the spectral signal in its molecular components without any expensive
postprocessing and any localization of the charge density or the wave
function.
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Affiliation(s)
- Daria Ruth Galimberti
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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28
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Rehl B, Ma E, Parshotam S, DeWalt-Kerian EL, Liu T, Geiger FM, Gibbs JM. Water Structure in the Electrical Double Layer and the Contributions to the Total Interfacial Potential at Different Surface Charge Densities. J Am Chem Soc 2022; 144:16338-16349. [PMID: 36042195 DOI: 10.1021/jacs.2c01830] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The electric double layer governs the processes of all charged surfaces in aqueous solutions; however, elucidating the structure of the water molecules is challenging for even the most advanced spectroscopic techniques. Here, we present the individual Stern layer and diffuse layer OH stretching spectra at the silica/water interface in the presence of NaCl over a wide pH range using a combination of vibrational sum frequency generation spectroscopy, heterodyned second harmonic generation, and streaming potential measurements. We find that the Stern layer water molecules and diffuse layer water molecules respond differently to pH changes: unlike the diffuse layer, whose water molecules remain net-oriented in one direction, water molecules in the Stern layer flip their net orientation as the solution pH is reduced from basic to acidic. We obtain an experimental estimate of the non-Gouy-Chapman (Stern) potential contribution to the total potential drop across the insulator/electrolyte interface and discuss it in the context of dipolar, quadrupolar, and higher order potential contributions that vary with the observed changes in the net orientation of water in the Stern layer. Our findings show that a purely Gouy-Chapman (Stern) view is insufficient to accurately describe the electrical double layer of aqueous interfaces.
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Affiliation(s)
- Benjamin Rehl
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Emily Ma
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Shyam Parshotam
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Emma L DeWalt-Kerian
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Tianli Liu
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Franz M Geiger
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Julianne M Gibbs
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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29
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Wu Y, Ling H, Qian Y, Hu Y, Niu B, Lin X, Kong XY, Jiang L, Wen L. Wetting-Induced Water Promoted Flow on Tunable Liquid-Liquid Interface-Based Nanopore Membrane System. ACS NANO 2022; 16:11092-11101. [PMID: 35714284 DOI: 10.1021/acsnano.2c03785] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Membrane separation provides effective methods for solving the global water crisis. Contemporary membrane systems depend on interfacial interactions between liquid and solid membrane matrixes. However, it may lead to a limiting permeate flux due to the large flow resistance at hydrophobic liquid-solid interfaces. Herein, the liquid-liquid interface with improved interface energy is reversibly introduced in membrane systems to boost wetting and reduce transport resistance. A series of interfaces were systematically explored to reveal mechanisms of wetting and boosted flow performances, which are further supported by simulations. Findings of this study highlight that interfacial liquids with lower surface energies, lower viscosities, and higher solubilities can effectively improve water flow without sacrificing rejection performance, achieving by transforming a solid-liquid interface into liquid-liquid interface interaction. It provides a concept to design advanced membrane systems for water purification (e.g., desalination and oil-water separation) and energy conversion processes.
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Affiliation(s)
- Yadong Wu
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Haoyang Ling
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yongchao Qian
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Yuhao Hu
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Bo Niu
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Xiangbin Lin
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xiang-Yu Kong
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
| | - Lei Jiang
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Liping Wen
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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30
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Yu CC, Seki T, Chiang KY, Tang F, Sun S, Bonn M, Nagata Y. Polarization-Dependent Heterodyne-Detected Sum-Frequency Generation Spectroscopy as a Tool to Explore Surface Molecular Orientation and Ångström-Scale Depth Profiling. J Phys Chem B 2022; 126:6113-6124. [PMID: 35849538 PMCID: PMC9421650 DOI: 10.1021/acs.jpcb.2c02178] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Sum-frequency generation (SFG) spectroscopy provides
a unique optical
probe for interfacial molecules with interface-specificity and molecular
specificity. SFG measurements can be further carried out at different
polarization combinations, but the target of the polarization-dependent
SFG is conventionally limited to investigating the molecular orientation.
Here, we explore the possibility of polarization-dependent SFG (PD-SFG)
measurements with heterodyne detection (HD-PD-SFG). We stress that
HD-PD-SFG enables accurate determination of the peak amplitude, a
key factor of the PD-SFG data. Subsequently, we outline that HD-PD-SFG
can be used not only for estimating the molecular orientation but
also for investigating the interfacial dielectric profile and studying
the depth profile of molecules. We further illustrate the variety
of combined simulation and PD-SFG studies.
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Affiliation(s)
- Chun-Chieh Yu
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Takakazu Seki
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Kuo-Yang Chiang
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Fujie Tang
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Shumei Sun
- Department of Physics and Applied Optics Beijing Area Major Laboratory, Beijing Normal University, Beijing 100875, China
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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31
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Controlled confined space effects on clustered water bound to hydrophobic nanosilica with nonpolar and polar co-adsorbates. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.128919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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32
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Lukas M, Backus EHG, Bonn M, Grechko M. Passively Stabilized Phase-Resolved Collinear SFG Spectroscopy Using a Displaced Sagnac Interferometer. J Phys Chem A 2022; 126:951-956. [PMID: 35113564 DOI: 10.1021/acs.jpca.1c10155] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Sum-frequency generation (SFG) vibrational spectroscopy is a powerful technique to study interfaces at the molecular level. Phase-resolved SFG (PR-SFG) spectroscopy provides direct information on interfacial molecules' orientation. However, its implementation is technologically demanding: it requires the generation of a local oscillator wave and control of its time delay with sub-fs accuracy. Commonly used noncollinear PR-SFG provides this control naturally but requires very accurate sample height control. Collinear PR-SFG spectroscopy is less demanding regarding sample positioning, but tuning the local oscillator time delay with this beam geometry is challenging. Here, we develop a collinear PR-SFG setup using a displaced Sagnac interferometer. This scheme allows full, independent control of the time delay and intensity of the local oscillator and provides long-time phase stabilization (better than 5° over 12 h) for the measured signal. This approach substantially reduces the complexity of an experimental setup and combines the advantages of collinear and noncollinear PR-SFG techniques.
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Affiliation(s)
- Max Lukas
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Ellen H G Backus
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany.,Department of Physical Chemistry, University of Vienna, 1090 Vienna, Austria
| | - Mischa Bonn
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany
| | - Maksim Grechko
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, 55128 Mainz, Germany
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33
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Brigiano FS, Gierada M, Tielens F, Pietrucci F. Mechanism and Free-Energy Landscape of Peptide Bond Formation at the Silica–Water Interface. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05635] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Flavio Siro Brigiano
- General Chemistry (ALGC), Materials Modeling Group, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Maciej Gierada
- General Chemistry (ALGC), Materials Modeling Group, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
- Faculty of Chemical Engineering and Technology, Cracow University of Technology, ul. Warszawska 24, 31-155 Kraków, Poland
| | - Frederik Tielens
- General Chemistry (ALGC), Materials Modeling Group, Vrije Universiteit Brussel, Pleinlaan 2, B-1050 Brussel, Belgium
| | - Fabio Pietrucci
- Sorbonne Université, Muséum National d’Histoire Naturelle, UMR CNRS 7590, IRD, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, F-75005 Paris, France
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34
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Klaassen A, Liu F, Mugele F, Siretanu I. Correlation between Electrostatic and Hydration Forces on Silica and Gibbsite Surfaces: An Atomic Force Microscopy Study. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:914-926. [PMID: 35025512 PMCID: PMC8793142 DOI: 10.1021/acs.langmuir.1c02077] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 12/29/2021] [Indexed: 06/14/2023]
Abstract
The balance between hydration and Derjaguin-Landau-Verwey-Overbeek (DLVO) forces at solid-liquid interfaces controls many processes, such as colloidal stability, wetting, electrochemistry, biomolecular self-assembly, and ion adsorption. Yet, the origin of molecular scale hydration forces and their relation to the surface charge density that controls the continuum scale electrostatic forces is poorly understood. We argue that these two types of forces are largely independent of each other. To support this hypothesis, we performed atomic force microscopy experiments using intermediate-sized tips that enable the simultaneous detection of DLVO and molecular scale oscillatory hydration forces at the interface between composite gibbsite:silica-aqueous electrolyte interfaces. We extract surface charge densities from forces measured at tip-sample separations of 1.5 nm and beyond using DLVO theory in combination with charge regulation boundary conditions for various pH values and salt concentrations. We simultaneously observe both colloidal scale DLVO forces and oscillatory hydration forces for an individual crystalline gibbsite particle and the underlying amorphous silica substrate for all fluid compositions investigated. While the diffuse layer charge varies with pH as expected, the oscillatory hydration forces are found to be largely independent of pH and salt concentration, supporting our hypothesis that both forces indeed have a very different origin. Oscillatory hydration forces are found to be distinctly more pronounced on gibbsite than on silica. We rationalize this observation based on the distribution of hydroxyl groups available for H bonding on the two distinct surfaces.
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Affiliation(s)
- Aram Klaassen
- Physics of Complex Fluids Group and
MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
| | - Fei Liu
- Physics of Complex Fluids Group and
MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
| | - Frieder Mugele
- Physics of Complex Fluids Group and
MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
| | - Igor Siretanu
- Physics of Complex Fluids Group and
MESA+ Institute, Faculty of Science and Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
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35
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Moon H, Collanton RP, Monroe JI, Casey TM, Shell MS, Han S, Scott SL. Evidence for Entropically Controlled Interfacial Hydration in Mesoporous Organosilicas. J Am Chem Soc 2022; 144:1766-1777. [PMID: 35041412 DOI: 10.1021/jacs.1c11342] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
At aqueous interfaces, the distribution and dynamics of adsorbates are modulated by the behavior of interfacial water. Hydration of a hydrophobic surface can store entropy via the ordering of interfacial water, which contributes to the Gibbs energy of solute binding. However, there is little experimental evidence for the existence of such entropic reservoirs, and virtually no precedent for their rational design in systems involving extended interfaces. In this study, two series of mesoporous silicas were modified in distinct ways: (1) progressively deeper thermal dehydroxylation, via condensation of surface silanols, and (2) increasing incorporation of nonpolar organic linkers into the silica framework. Both approaches result in decreasing average surface polarity, manifested in a blue-shift in the fluorescence of an adsorbed dye. For the inorganic silicas, hydrogen-bonding of water becomes less extensive as the number of surface silanols decreases. Overhauser dynamic nuclear polarization (ODNP) relaxometry indicates enhanced surface water diffusivity, reflecting a loss of enthalpic hydration. In contrast, organosilicas show a monotonic decrease in surface water diffusivity with decreasing polarity, reflecting enhanced hydrophobic hydration. Molecular dynamics simulations predict increased tetrahedrality of interfacial water for the organosilicas, implying increased ordering near the nm-size organic domains (relative to inorganic silicas, which necessarily lack such domains). These findings validate the prediction that hydrophobic hydration at interfaces is controlled by the microscopic length scale of the hydrophobic regions. They further suggest that the hydration thermodynamics of structurally heterogeneous silica surfaces can be tuned to promote adsorption, which in turn tunes the selectivity in catalytic reactions.
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Affiliation(s)
- Hyunjin Moon
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Ryan P Collanton
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Jacob I Monroe
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Thomas M Casey
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - M Scott Shell
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States.,Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Susannah L Scott
- Department of Chemical Engineering, University of California, Santa Barbara, California 93106-5080, United States.,Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
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36
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Ma E, Geiger FM. Divalent Ion Specific Outcomes on Stern Layer Structure and Total Surface Potential at the Silica:Water Interface. J Phys Chem A 2021; 125:10079-10088. [PMID: 34761927 DOI: 10.1021/acs.jpca.1c08143] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The second-order nonlinear susceptibility, χ(2), in the Stern layer and the total interfacial potential drop, Φ(0)tot, across the oxide:water interface are estimated from SHG amplitude and phase measurements for divalent cations (Mg2+, Ca2+, Sr2+, and Ba2+) at the silica:water interface at pH 5.8 and various ionic strengths. We find that interfacial structure and total potential depend strongly on ion valency. We observe statistically significant differences between the experimentally determined χ(2) value for NaCl and that of the alkali earth series but smaller differences between ions of the same valency in that series. These differences are particularly pronounced at intermediate salt concentrations, which we attribute to the influence of hydration structure in the Stern layer. Furthermore, we corroborate the differences by examining the effects of anion substitution (SO42- for Cl-). Finally, we identify that hysteresis in measuring the reversibility of ion adsorption and desorption at fused silica in forward and reverse titrations manifests itself both in Stern layer structure and in total interfacial potential for some of the salts, most notably for CaCl2 and MgSO4 but less so for BaCl2 and NaCl.
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Affiliation(s)
- Emily Ma
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
| | - Franz M Geiger
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60660, United States
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37
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Söngen H, Schlegel SJ, Morais Jaques Y, Tracey J, Hosseinpour S, Hwang D, Bechstein R, Bonn M, Foster AS, Kühnle A, Backus EH. Water Orientation at the Calcite-Water Interface. J Phys Chem Lett 2021; 12:7605-7611. [PMID: 34350760 PMCID: PMC8365774 DOI: 10.1021/acs.jpclett.1c01729] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Accepted: 08/02/2021] [Indexed: 06/13/2023]
Abstract
Mineral-water interfaces play an important role in many natural as well as technological fields. Fundamental properties of these interfaces are governed by the presence of the interfacial water and its specific structure at the surface. Calcite is particularly interesting as a dominant rock-forming mineral in the earth's crust. Here, we combine atomic force microscopy, sum-frequency generation spectroscopy, and molecular dynamics simulations to determine the position and orientation of the water molecules in the hydration layers of the calcite surface with high resolution. While atomic force microscopy provides detailed information about the position of the water molecules at the interface, sum-frequency generation spectroscopy can deduce the orientation of the water molecules. Comparison of the calcite-water interface to the interfaces of magnesite-water, magnesite-ethanol, and calcite-ethanol reveals a comprehensive picture with opposite water orientations in the first and second layer of the interface, which is corroborated by the molecular dynamics simulations.
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Affiliation(s)
- Hagen Söngen
- Physical
Chemistry I, Faculty of Chemistry, Bielefeld
University, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Simon J. Schlegel
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ygor Morais Jaques
- Department
of Applied Physics, Aalto University, Helsinki, FI-00076, Finland
| | - John Tracey
- Department
of Applied Physics, Aalto University, Helsinki, FI-00076, Finland
| | - Saman Hosseinpour
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Doyk Hwang
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ralf Bechstein
- Physical
Chemistry I, Faculty of Chemistry, Bielefeld
University, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Mischa Bonn
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Adam S. Foster
- Department
of Applied Physics, Aalto University, Helsinki, FI-00076, Finland
- Nano
Life Science Institute (WPI-NanoLSI), Kanazawa
University, Kanazawa 920-1192, Japan
| | - Angelika Kühnle
- Physical
Chemistry I, Faculty of Chemistry, Bielefeld
University, Universitätsstrasse 25, 33615 Bielefeld, Germany
| | - Ellen H.G. Backus
- Max
Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Department
of Physical Chemistry, University of Vienna, Währinger Strasse 42, 1090 Vienna Austria
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38
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Grad P, Agmo Hernández V, Edwards K. Avoiding artifacts in liposome leakage measurements via cuvette- and liposome-surface modifications. J Liposome Res 2021; 32:237-249. [PMID: 34369250 DOI: 10.1080/08982104.2021.1944188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The barrier properties of lipid membranes are often determined by investigating their solute permeability with the help of spectroscopic methods and the use of liposome-encapsulated self-quenching fluorescent dyes, for example, Carboxyfluorescein (CF). It was shown previously that liposome-surface interactions, and thus the choice of cuvette material, influence the result of such spectroscopic permeability/leakage experiments. In this work, we explore different methods to minimize the artifacts observed in spontaneous leakage measurements performed with cholesterol-containing liposomes. The spontaneous leakage of CF from liposomes with different composition and surface properties is monitored in cuvettes composed of quartz, polystyrene (PS), and Poly(methyl methacrylate) (PMMA). Our results show that significantly different leakage profiles are recorded for the exact same liposome batch depending on the cuvette material used. Quartz Crystal Microbalance with Dissipation Monitoring (QCM-D) experiments indicate that these discrepancies likely arise from side processes occurring at the solution-cuvette interface, mainly, the attaching and spreading of liposomes. Further, we show that in some cases it is possible to minimize liposome-cuvette interactions, and reduce the experimental artifacts, by supplementing the liposomes with polyethylene glycol (PEG)-grafted lipids or gangliosides, and/or by pre-adsorbing free PEG to the cuvette walls. The collected data suggest that quartz cuvettes modified by adsorption of PEG8000 are suitable for spontaneous leakage experiments with POPC:cholesterol-based liposomes, while other cuvette materials perform poorly in the same experiments.
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Affiliation(s)
- Philipp Grad
- Department of Chemistry - Ångström Laboratory, Uppsala University, Uppsala, Sweden
| | | | - Katarina Edwards
- Department of Chemistry - Ångström Laboratory, Uppsala University, Uppsala, Sweden
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39
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Adams E, Pezzotti S, Ahlers J, Rüttermann M, Levin M, Goldenzweig A, Peleg Y, Fleishman SJ, Sagi I, Havenith M. Local Mutations Can Serve as a Game Changer for Global Protein Solvent Interaction. JACS AU 2021; 1:1076-1085. [PMID: 34337607 PMCID: PMC8317155 DOI: 10.1021/jacsau.1c00155] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Indexed: 05/15/2023]
Abstract
Although it is well-known that limited local mutations of enzymes, such as matrix metalloproteinases (MMPs), may change enzyme activity by orders of magnitude as well as its stability, the completely rational design of proteins is still challenging. These local changes alter the electrostatic potential and thus local electrostatic fields, which impacts the dynamics of water molecules close the protein surface. Here we show by a combined computational design, experimental, and molecular dynamics (MD) study that local mutations have not only a local but also a global effect on the solvent: In the specific case of the matrix metalloprotease MMP14, we found that the nature of local mutations, coupled with surface morphology, have the ability to influence large patches of the water hydrogen-bonding network at the protein surface, which is correlated with stability. The solvent contribution can be experimentally probed via terahertz (THz) spectroscopy, thus opening the door to the exciting perspective of rational protein design in which a systematic tuning of hydration water properties allows manipulation of protein stability and enzymatic activity.
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Affiliation(s)
- Ellen
M. Adams
- Lehrstuhl
für Physkalische Chemie II, Ruhr
Universität Bochum, 44801 Bochum, Germany
| | - Simone Pezzotti
- Lehrstuhl
für Physkalische Chemie II, Ruhr
Universität Bochum, 44801 Bochum, Germany
| | - Jonas Ahlers
- Lehrstuhl
für Physkalische Chemie II, Ruhr
Universität Bochum, 44801 Bochum, Germany
| | - Maximilian Rüttermann
- Lehrstuhl
für Physkalische Chemie II, Ruhr
Universität Bochum, 44801 Bochum, Germany
| | - Maxim Levin
- Department
of Biological Regulation, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Adi Goldenzweig
- Department
of Biomolecular Sciences, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Yoav Peleg
- Structural
Proteomics Unit, Department of Life Sciences Core Facilities, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Sarel J. Fleishman
- Department
of Biomolecular Sciences, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Irit Sagi
- Department
of Biological Regulation, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Martina Havenith
- Lehrstuhl
für Physkalische Chemie II, Ruhr
Universität Bochum, 44801 Bochum, Germany
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40
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Abstract
The ubiquity of aqueous solutions in contact with charged surfaces and the realization that the molecular-level details of water-surface interactions often determine interfacial functions and properties relevant in many natural processes have led to intensive research. Even so, many open questions remain regarding the molecular picture of the interfacial organization and preferential alignment of water molecules, as well as the structure of water molecules and ion distributions at different charged interfaces. While water, solutes and charge are present in each of these systems, the substrate can range from living tissues to metals. This diversity in substrates has led to different communities considering each of these types of aqueous interface. In this Review, by considering water in contact with metals, oxides and biomembranes, we show the essential similarity of these disparate systems. While in each case the classical mean-field theories can explain many macroscopic and mesoscopic observations, it soon becomes apparent that such theories fail to explain phenomena for which molecular properties are relevant, such as interfacial chemical conversion. We highlight the current knowledge and limitations in our understanding and end with a view towards future opportunities in the field.
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41
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Bui TT, Colón LA, Velarde L. Intermolecular Interactions at the Silica-Liquid Interface Modulate the Fermi Resonance Coupling in Surface Methanol. J Phys Chem Lett 2021; 12:5695-5702. [PMID: 34115940 DOI: 10.1021/acs.jpclett.1c01015] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The buried solid/liquid interface between hydrophilic fused silica and binary solvent mixtures of acetonitrile (MeCN) and methanol (MeOH) was studied with vibrational sum-frequency generation (vSFG) spectroscopy. Our data showed that at high relative concentrations of methanol, the Fermi resonance peak in the vSFG spectrum is greatly suppressed, and it progressively gains intensity as methanol is diluted with perdeuterated acetonitrile. This phenomenon is quantified by the Fermi resonance coupling coefficient, W, extracted using a two-level model, as well as the experimental intensity ratio, R, of the methyl Fermi resonance band to that of the symmetric stretch. At a 1.0 MeOH mole fraction, W and R values were 10 ± 10 cm-1 and 0.01 ± 0.02, respectively, whereas at a 0.1 mole fraction, W and R increased to 46 ± 4 cm-1 and 0.43 ± 0.16, respectively. This indicates that solvation with acetonitrile effectively tunes the Fermi coupling of methanol vibrations at the silica/liquid interface.
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Affiliation(s)
- Thomas T Bui
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Luis A Colón
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
| | - Luis Velarde
- Department of Chemistry, University at Buffalo, State University of New York, Buffalo, New York 14260-3000, United States
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42
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Kim D, Kim E, Park S, Kim S, Min BK, Yoon HJ, Kwak K, Cho M. Wettability of graphene and interfacial water structure. Chem 2021. [DOI: 10.1016/j.chempr.2021.03.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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43
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Backus EHG, Schaefer J, Bonn M. Probing the Mineral-Water Interface with Nonlinear Optical Spectroscopy. Angew Chem Int Ed Engl 2021; 60:10482-10501. [PMID: 32558984 PMCID: PMC8247323 DOI: 10.1002/anie.202003085] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 05/18/2020] [Indexed: 12/21/2022]
Abstract
The interaction between minerals and water is manifold and complex: the mineral surface can be (de)protonated by water, thereby changing its charge; mineral ions dissolved into the aqueous phase screen the surface charges. Both factors affect the interaction with water. Intrinsically molecular-level processes and interactions govern macroscopic phenomena, such as flow-induced dissolution, wetting, and charging. This realization is increasingly prompting molecular-level studies of mineral-water interfaces. Here, we provide an overview of recent developments in surface-specific nonlinear spectroscopy techniques such as sum frequency and second harmonic generation (SFG/SHG), which can provide information about the molecular arrangement of the first few layers of water molecules at the mineral surface. The results illustrate the subtleties of both chemical and physical interactions between water and the mineral as well as the critical role of mineral dissolution and other ions in solution for determining those interactions.
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Affiliation(s)
- Ellen H. G. Backus
- Max Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
- Department of Physical ChemistryUniversity of ViennaWähringer Strasse 421090ViennaAustria
| | - Jan Schaefer
- Max Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
| | - Mischa Bonn
- Max Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
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44
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Backus EHG, Schaefer J, Bonn M. Untersuchung der Mineral‐Wasser‐Grenzschicht mit nicht‐linearer optischer Spektroskopie. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202003085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Ellen H. G. Backus
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
- Institut für Physikalische Chemie Universität Wien Währinger Straße 42 1090 Wien Österreich
| | - Jan Schaefer
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
| | - Mischa Bonn
- Max-Planck-Institut für Polymerforschung Ackermannweg 10 55128 Mainz Deutschland
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45
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Rezaei M, Mitterwallner BG, Loche P, Uematsu Y, Netz RR, Bonthuis DJ. Interfacial, Electroviscous, and Nonlinear Dielectric Effects on Electrokinetics at Highly Charged Surfaces. J Phys Chem B 2021; 125:4767-4778. [PMID: 33939436 PMCID: PMC8154604 DOI: 10.1021/acs.jpcb.0c11280] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The dielectric constant
and the viscosity of water at the interface
of hydrophilic surfaces differ from their bulk values, and it has
been proposed that the deviation is caused by the strong electric
field and the high ion concentration in the interfacial layer. We
calculate the dependence of the dielectric constant and the viscosity
of bulk electrolytes on the electric field and the salt concentration.
Incorporating the concentration and field-dependent dielectric constant
and viscosity in the extended Poisson–Boltzmann and Stokes
equations, we calculate the electro-osmotic mobility. We compare the
results to literature experimental data and explicit molecular dynamics
simulations of OH-terminated surfaces and show that it is necessary
to additionally include the presence of a subnanometer wide interfacial
water layer, the properties of which are drastically transformed by
the sheer presence of the interface. We conclude that the origin of
the anomalous behavior of aqueous interfacial layers cannot be found
in electrostriction or electroviscous effects caused by the interfacial
electric field and ion concentration. Instead, it is primarily caused
by the intrinsic ordering and orientation of the interfacial water
layer.
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Affiliation(s)
- Majid Rezaei
- Fachbereich Physik, Freie Universität Berlin, 14195 Berlin, Germany
| | | | - Philip Loche
- Fachbereich Physik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Yuki Uematsu
- Department of Physics, Kyushu University, 819-0395 Fukuoka, Japan
| | - Roland R Netz
- Fachbereich Physik, Freie Universität Berlin, 14195 Berlin, Germany
| | - Douwe Jan Bonthuis
- Institute of Theoretical and Computational Physics, Graz University of Technology, 8010 Graz, Austria
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46
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Pezzotti S, Serva A, Sebastiani F, Brigiano FS, Galimberti DR, Potier L, Alfarano S, Schwaab G, Havenith M, Gaigeot MP. Molecular Fingerprints of Hydrophobicity at Aqueous Interfaces from Theory and Vibrational Spectroscopies. J Phys Chem Lett 2021; 12:3827-3836. [PMID: 33852317 PMCID: PMC9004482 DOI: 10.1021/acs.jpclett.1c00257] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/09/2021] [Indexed: 05/28/2023]
Abstract
Hydrophobicity/hydrophilicity of aqueous interfaces at the molecular level results from a subtle balance in the water-water and water-surface interactions. This is characterized here via density functional theory-molecular dynamics (DFT-MD) coupled with vibrational sum frequency generation (SFG) and THz-IR absorption spectroscopies. We show that water at the interface with a series of weakly interacting materials is organized into a two-dimensional hydrogen-bonded network (2D-HB-network), which is also found above some macroscopically hydrophilic silica and alumina surfaces. These results are rationalized through a descriptor that measures the number of "vertical" and "horizontal" hydrogen bonds formed by interfacial water, quantifying the competition between water-surface and water-water interactions. The 2D-HB-network is directly revealed by THz-IR absorption spectroscopy, while the competition of water-water and water-surface interactions is quantified from SFG markers. The combination of SFG and THz-IR spectroscopies is thus found to be a compelling tool to characterize the finest details of molecular hydrophobicity at aqueous interfaces.
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Affiliation(s)
- Simone Pezzotti
- Université
Paris-Saclay, Univ Evry, CNRS, LAMBE
UMR8587, 91025 Evry-Courcouronnes, France
| | - Alessandra Serva
- Université
Paris-Saclay, Univ Evry, CNRS, LAMBE
UMR8587, 91025 Evry-Courcouronnes, France
| | - Federico Sebastiani
- Department
of Physical Chemistry II, Ruhr University
Bochum, D-44801 Bochum, Germany
| | - Flavio Siro Brigiano
- Université
Paris-Saclay, Univ Evry, CNRS, LAMBE
UMR8587, 91025 Evry-Courcouronnes, France
| | - Daria Ruth Galimberti
- Université
Paris-Saclay, Univ Evry, CNRS, LAMBE
UMR8587, 91025 Evry-Courcouronnes, France
| | - Louis Potier
- Université
Paris-Saclay, Univ Evry, CNRS, LAMBE
UMR8587, 91025 Evry-Courcouronnes, France
| | - Serena Alfarano
- Department
of Physical Chemistry II, Ruhr University
Bochum, D-44801 Bochum, Germany
| | - Gerhard Schwaab
- Department
of Physical Chemistry II, Ruhr University
Bochum, D-44801 Bochum, Germany
| | - Martina Havenith
- Department
of Physical Chemistry II, Ruhr University
Bochum, D-44801 Bochum, Germany
| | - Marie-Pierre Gaigeot
- Université
Paris-Saclay, Univ Evry, CNRS, LAMBE
UMR8587, 91025 Evry-Courcouronnes, France
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47
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Ahlers J, Adams EM, Bader V, Pezzotti S, Winklhofer KF, Tatzelt J, Havenith M. The key role of solvent in condensation: Mapping water in liquid-liquid phase-separated FUS. Biophys J 2021; 120:1266-1275. [PMID: 33515602 PMCID: PMC8059208 DOI: 10.1016/j.bpj.2021.01.019] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 11/21/2020] [Accepted: 01/19/2021] [Indexed: 01/09/2023] Open
Abstract
Formation of biomolecular condensates through liquid-liquid phase separation (LLPS) has emerged as a pervasive principle in cell biology, allowing compartmentalization and spatiotemporal regulation of dynamic cellular processes. Proteins that form condensates under physiological conditions often contain intrinsically disordered regions with low-complexity domains. Among them, the RNA-binding proteins FUS and TDP-43 have been a focus of intense investigation because aberrant condensation and aggregation of these proteins is linked to neurodegenerative diseases such as amyotrophic lateral sclerosis and frontotemporal dementia. LLPS occurs when protein-rich condensates form surrounded by a dilute aqueous solution. LLPS is per se entropically unfavorable. Energetically favorable multivalent protein-protein interactions are one important aspect to offset entropic costs. Another proposed aspect is the release of entropically unfavorable preordered hydration water into the bulk. We used attenuated total reflection spectroscopy in the terahertz frequency range to characterize the changes in the hydrogen bonding network accompanying the FUS enrichment in liquid-liquid phase-separated droplets to provide experimental evidence for the key role of the solvent as a thermodynamic driving force. The FUS concentration inside LLPS droplets was determined to be increased to 2.0 mM independent of the initial protein concentration (5 or 10 μM solutions) by fluorescence measurements. With terahertz spectroscopy, we revealed a dewetting of hydrophobic side chains in phase-separated FUS. Thus, the release of entropically unfavorable water populations into the bulk goes hand in hand with enthalpically favorable protein-protein interaction. Both changes are energetically favorable, and our study shows that both contribute to the thermodynamic driving force in phase separation.
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Affiliation(s)
- Jonas Ahlers
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany
| | - Ellen M Adams
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany
| | - Verian Bader
- Department Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Simone Pezzotti
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany
| | - Konstanze F Winklhofer
- Department Molecular Cell Biology, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Jörg Tatzelt
- Department Biochemistry of Neurodegenerative Diseases, Institute of Biochemistry and Pathobiochemistry, Ruhr-University Bochum, Bochum, Germany
| | - Martina Havenith
- Department Physical Chemistry, Ruhr-University Bochum, Bochum, Germany.
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48
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Rehl B, Gibbs JM. Role of Ions on the Surface-Bound Water Structure at the Silica/Water Interface: Identifying the Spectral Signature of Stability. J Phys Chem Lett 2021; 12:2854-2864. [PMID: 33720727 DOI: 10.1021/acs.jpclett.0c03565] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Isolating the hydrogen-bonding structure of water immediately at the surface is challenging, even with surface-specific techniques like sum-frequency generation (SFG), because of the presence of aligned water further away in the diffuse layer. Here, we combine zeta potential and SFG intensity measurements with the maximum entropy method referenced to reported phase-sensitive SFG and second-harmonic generation results to deconvolute the SFG spectral contributions of the surface waters from those in the diffuse layer. Deconvolution reveals that at very low ionic strength, the surface water structure is similar to that of a neutral silica surface near the point-of-zero-charge with waters in different hydrogen-bonding environments oriented in opposite directions. This similarity suggests that the known metastability of silica colloids against aggregation under both conditions could arise from this distinct surface water structure. Upon the addition of salt, significant restructuring of water is observed, leading to a net decrease in order at the surface.
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Affiliation(s)
- Benjamin Rehl
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
| | - Julianne M Gibbs
- Department of Chemistry, University of Alberta, Edmonton, Alberta T6G 2G2, Canada
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49
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Smirnov KS. Structure and sum-frequency generation spectra of water on neutral hydroxylated silica surfaces. Phys Chem Chem Phys 2021; 23:6929-6949. [PMID: 33729227 DOI: 10.1039/d0cp06465c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Structural organization and vibrational sum-frequency generation (VSFG) spectra of water on crystalline and amorphous neutral silica surfaces were investigated by classical molecular dynamics simulations. The liquid phase represented with neat water and 1 M NaCl solution was analysed in terms of bonded interfacial layer (BIL), diffuse layer (DL) and bulk region. The simulations show that the structure of BIL depends on the surface morphology and density of surface OH groups. The water-silanol H-bond network and BIL structure are mainly insensitive to the presence of ions in the liquid phase. Molecules in DL of SiO2/neat water interfaces preferentially orient their OH bonds towards the surfaces. This effect is directly related to an effective negative charge of formally neutral surfaces. Ions of the electrolyte solution affect the intermolecular structure in DL by screening the surface electric field and by the chaotropic effect. Calculated phase-sensitive VSFG (Im[χ(2)]) spectrum of BIL features low-frequency negative and high-frequency positive bands. Characteristics of the positive band reflect the strength of water-surface interactions and surface crystallinity, while the position and shape of the negative band are common to all interfaces. The Im[χ(2)] spectrum of DL is dominated by a contribution from the third-order χ(3) susceptibility with the sign of the contribution directly related to the sign of electrostatic potential in the interfacial region. The DL spectrum is strongly affected by the presence of solvated ions. The computed intensity and Im[χ(2)] spectra of the amorphous silica/NaCl solution interface are in a good agreement with the conventional and phase-sensitive experimental VSFG spectra of fused SiO2/water system at low pH, in contrast to the spectra of the amorphous silica/neat water interface. Origins of the discrepancy are discussed.
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Affiliation(s)
- Konstantin S Smirnov
- Univ. Lille, CNRS, UMR 8516 - LASIRe - Laboratoire Avancé de Spectroscopie pour les Interactions la Réactivité et l'Environnement, F-59000 Lille, France.
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50
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Ojha D, Kühne TD. Hydrogen bond dynamics of interfacial water molecules revealed from two-dimensional vibrational sum-frequency generation spectroscopy. Sci Rep 2021; 11:2456. [PMID: 33510246 PMCID: PMC7844302 DOI: 10.1038/s41598-021-81635-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Accepted: 01/06/2021] [Indexed: 11/17/2022] Open
Abstract
Vibrational sum-frequency generation (vSFG) spectroscopy allows the study of the structure and dynamics of interfacial systems. In the present work, we provide a simple recipe, based on a narrowband IR pump and broadband vSFG probe technique, to computationally obtain the two-dimensional vSFG spectrum of water molecules at the air-water interface. Using this technique, to study the time-dependent spectral evolution of hydrogen-bonded and free water molecules, we demonstrate that at the interface, the vibrational spectral dynamics of the free OH bond is faster than that of the bonded OH mode.
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Affiliation(s)
- Deepak Ojha
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Chair of Theoretical Chemistry, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany
| | - Thomas D Kühne
- Dynamics of Condensed Matter and Center for Sustainable Systems Design, Chair of Theoretical Chemistry, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany.
- Paderborn Center for Parallel Computing and Institute for Lightweight Design, Paderborn University, Warburger Str. 100, 33098, Paderborn, Germany.
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