1
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Shchegravina ES, Tretiakova DS, Sitdikova AR, Usova SD, Boldyrev IA, Alekseeva AS, Svirshchevskaya EV, Vodovozova EL, Fedorov AY. Design and preparation of pH-sensitive cytotoxic liposomal formulations containing antitumor colchicine analogues for target release. J Liposome Res 2024; 34:399-410. [PMID: 37867342 DOI: 10.1080/08982104.2023.2274428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2023] [Accepted: 10/18/2023] [Indexed: 10/24/2023]
Abstract
Herein, we describe the synthesis of pH-sensitive lipophilic colchicine prodrugs for liposomal bilayer inclusion, as well as preparation and characterization of presumably stealth PEGylated liposomes with above-mentioned prodrugs. These formulations liberate strongly cytotoxic colchicinoid derivatives selectively under slightly acidic tumor-associated conditions, ensuring tumor-targeted delivery of the compounds. The design of the prodrugs is addressed to pH-triggered release of active compounds in the slight acidic media, that corresponds to tumor microenvironment, while keeping sufficient stability of the whole formulation at physiological pH. Correlations between the structure of the conjugates, their hydrolytic stability, colloidal stability, ability of the prodrug retention in the lipid bilayer are described. Several formulations were found promising for further development and in vivo investigations.
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Affiliation(s)
- Ekaterina S Shchegravina
- Department of Organic Chemistry, UNN Lobachevsky University, Nizhny Novgorod, Russian Federation
| | - Daria S Tretiakova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Alsu R Sitdikova
- Department of Organic Chemistry, UNN Lobachevsky University, Nizhny Novgorod, Russian Federation
| | - Sofia D Usova
- N.D. Zelinsky Insitute of Organic Chemistry RAS, Moscow, Russian Federation
| | - Ivan A Boldyrev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Anna S Alekseeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | | | - Elena L Vodovozova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry RAS, Moscow, Russian Federation
| | - Alexey Yu Fedorov
- Department of Organic Chemistry, UNN Lobachevsky University, Nizhny Novgorod, Russian Federation
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2
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Schneck E, Reed J, Seki T, Nagata Y, Kanduč M. Experimental and simulation-based characterization of surfactant adsorption layers at fluid interfaces. Adv Colloid Interface Sci 2024; 331:103237. [PMID: 38959812 DOI: 10.1016/j.cis.2024.103237] [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: 11/07/2023] [Revised: 06/10/2024] [Accepted: 06/13/2024] [Indexed: 07/05/2024]
Abstract
Adsorption of surfactants to fluid interfaces occurs in numerous technological and daily-life contexts. The coverage at the interface and other properties of the formed adsorption layers determine the performance of a surfactant with regard to the desired application. Given the importance of these applications, there is a great demand for the comprehensive characterization and understanding of surfactant adsorption layers. In this review, we provide an overview of suitable experimental and simulation-based techniques and review the literature in which they were used for the investigation of surfactant adsorption layers. We come to the conclusion that, while these techniques have been successfully applied to investigate Langmuir monolayers of water-insoluble surfactants, their application to the study of Gibbs adsorption layers of water-soluble surfactants has not been fully exploited. Finally, we emphasize the great potential of these methods in providing a deeper understanding of the behavior of soluble surfactants at interfaces, which is crucial for optimizing their performance in various applications.
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Affiliation(s)
- Emanuel Schneck
- Department of Physics, Technische Universität Darmstadt, Hochschulstrasse 8, 64289 Darmstadt, Germany.
| | - Joshua Reed
- Department of Physics, Technische Universität Darmstadt, Hochschulstrasse 8, 64289 Darmstadt, Germany
| | - Takakazu Seki
- Graduate School of Science and Technology, Hirosaki University, Hirosaki, 036-8561 Aomori, Japan
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
| | - Matej Kanduč
- Department of Theoretical Physics, Jožef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia.
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3
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Paul S, Mondal S, Shenogina I, Cui Q. The molecular basis for the increased stability of the FUS-LC fibril at the anionic membrane- and air-water interfaces. Chem Sci 2024; 15:13788-13799. [PMID: 39211498 PMCID: PMC11352777 DOI: 10.1039/d4sc02295e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 07/22/2024] [Indexed: 09/04/2024] Open
Abstract
Self-organization of biomolecules can lead to the formation of liquid droplets, hydrogels, and irreversible aggregates that bear immense significance in biology and diseases. Despite the considerable number of studies conducted on biomolecular condensation in bulk solution, there is still a lack of understanding of how different surfaces regulate the condensation process. In this context, recent studies showed that, in contrast to zwitterionic lipid membranes, anionic membranes promoted the production of liquid droplets of FUsed in Sarcoma Low Complexity domain (FUS-LC) despite exhibiting no specific protein-lipid interactions. Moreover, the air-water interface led to a solid fibril-like aggregate of FUS-LC. The molecular mechanism of condensation/aggregation of proteins in response to surfaces of various charged states or levels of hydrophobicity remains to be better elucidated. Here, we provide initial insights into this question by investigating the stability of a small β fibril state of FUS-LC in bulk solution vs. membrane- and air-water interfaces. We perform multiple independent molecular dynamics simulations with distinct starting conformations for each system to demonstrate the statistical significance of our findings. Our study demonstrates the stability of the FUS-LC fibril in the presence of anionic membranes on the μs timescale while the fibril falls apart in bulk solution. We observe that a zwitterionic membrane does not enhance the stability of the fibril and 1,2-dioleoyl-sn-glycero-3-phospho-l-serine (DOPS) has a higher propensity to stabilize the fibril than dioleoylphosphatidylglycerol (DOPG), in qualitative agreement with experiments. We further show that the fibril becomes more stable at the air-water interface. We pinpoint interfacial solvation at the membrane- and air-water interfaces as a key factor that contributes to the stabilization of the peptide assembly.
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Affiliation(s)
- Sanjoy Paul
- Department of Chemistry, Boston University 590 Commonwealth Avenue Massachusetts-02215 USA
| | - Sayantan Mondal
- Department of Chemistry, Boston University 590 Commonwealth Avenue Massachusetts-02215 USA
| | - Irina Shenogina
- Department of Physics, University of Illinois Urbana-Champaign USA
| | - Qiang Cui
- Department of Chemistry, Boston University 590 Commonwealth Avenue Massachusetts-02215 USA
- Departments of Physics, and Biomedical Engineering, Boston University Massachusetts-02215 USA
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4
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Han T, Xu W, Han J, Adibnia V, He H, Zhang C, Luo J. Counterion Distribution in the Stern Layer on Charged Surfaces. NANO LETTERS 2024; 24:10443-10450. [PMID: 39140834 DOI: 10.1021/acs.nanolett.4c01230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/15/2024]
Abstract
Counterion adsorption at the solid-liquid interface affects numerous applications. However, the counterion adsorption density in the Stern layer has remained poorly evaluated. Here we report the direct determination of surface charge density at the shear plane between the Stern layer and the diffuse layer. By the Grahame equation extension and streaming current measurements for different solid surfaces in different aqueous electrolytes, we are able to obtain the counterion adsorption density in the Stern layer, which is mainly related to the surface charge density but is less affected by the bulk ion concentration. The charge inversion concentration is further found to be sensitive to the ion type and ion valence rather than to the charged surface, which is attributed to the ionic competitive adsorption and ion-ion correlations. Our findings offer a framework for understanding ion distribution in many physical and chemical processes where the Stern layer is ubiquitous.
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Affiliation(s)
- Tianyi Han
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Wanxing Xu
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Jie Han
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Vahid Adibnia
- School of Biomedical Engineering, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Hongjiang He
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Chenhui Zhang
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, People's Republic of China
| | - Jianbin Luo
- State Key Laboratory of Tribology in Advanced Equipment, Tsinghua University, Beijing 100084, People's Republic of China
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5
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Smirnov KS. Effects of Surface Charge Distribution and Electrolyte Ions on the Nonlinear Spectra of Model Solid-Water Interfaces. Molecules 2024; 29:3758. [PMID: 39202839 PMCID: PMC11356812 DOI: 10.3390/molecules29163758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2024] [Revised: 07/31/2024] [Accepted: 08/01/2024] [Indexed: 09/03/2024] Open
Abstract
Molecular dynamics simulations of model charged solid/water interfaces were carried out to provide insight about the relationship between the second-order nonlinear susceptibility χ(2) and the structure of the interfacial water layer. The results of the calculations reveal that the density fluctuations of water extend to about 12 Å from the surface regardless of the system, while the orientational ordering of molecules is long-ranged and is sensitive to the presence of electrolytes. The charge localization on the surface was found to affect only the high-frequency part of the Im[χ(2)] spectrum, and the addition of salt has very little effect on the spectrum of the first water layer. For solid/neat water interfaces, the spectroscopically active part of the liquid phase has a thickness largely exceeding the region of density fluctuations, and this long-ranged nonlinear activity is mediated by the electric field of the molecules. The electrolyte ions and their hydration shells act in a destructive way on the molecular field. This effect, combined with the screening of the surface charge by ions, drastically reduces the thickness of the spectroscopic diffuse layer. There is an electrolyte concentration at which the nonlinear response of the diffuse layer is suppressed and the χ(2) spectrum of the interface essentially coincides with that of the first water layer.
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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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6
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Ma YH, Li B, Wang C, Yang J, Han X, Lu X. Unsaturation effects on lipid transmembrane asymmetry. J Chem Phys 2024; 160:215102. [PMID: 38842495 DOI: 10.1063/5.0209950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Accepted: 05/15/2024] [Indexed: 06/07/2024] Open
Abstract
Within cell plasma membranes, unsaturated lipids are asymmetrically distributed over the inner and outer leaflets, offering an attractive local structural feature. However, the mechanism to keep lipid transmembrane asymmetry and the closely related transmembrane movement (flip-flop) for unsaturated lipids remain poorly understood. Here, we applied sum frequency generation vibrational spectroscopy to investigate this lipid transmembrane asymmetry upon mimicking the cell membrane homeostatic processes. On the one hand, unsaturated lipids were found to hinder the flip-flop process and preserve lipid transmembrane asymmetry in model cell membranes, owing to the steric hindrance caused by their bent tails. On the other hand, local unsaturated lipids in the mixed unsaturated/saturated lipid bilayer were conducive to the formation of the local asymmetry. Therefore, lipid unsaturation can be recognized as an intrinsic key factor to form and maintain lipid transmembrane asymmetry in cell membranes.
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Affiliation(s)
- Yong-Hao Ma
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Bolin Li
- Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei 230031, China
| | - Chu Wang
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Jingjing Yang
- Department of Biochemistry and Molecular Biology, School of Medicine and Holistic Integrative Medicine, Jiangsu Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Xiaofeng Han
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Xiaolin Lu
- State Key Laboratory of Digital Medical Engineering, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
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7
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Saak CM, Dreier LB, Machel K, Bonn M, Backus EHG. Biological lipid hydration: distinct mechanisms of interfacial water alignment and charge screening for model lipid membranes. Faraday Discuss 2024; 249:317-333. [PMID: 37795538 DOI: 10.1039/d3fd00117b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
Studying lipid monolayers as model biological membranes, we demonstrate that water molecules interfacing with different model membranes can display preferential orientation for two distinct reasons: due to charges on the membrane, and due to large dipole fields resulting from zwitterionic headgroups. This preferential water orientation caused by the charge or the dipolar field can be effectively neutralized to net-zero water orientation by introducing monolayer counter-charges (i.e. lipids with oppositely charged headgroups). Following the Gouy-Chapman model, the effect of monolayer surface charge on water orientation is furthermore strongly dependent on the electrolyte concentration and thus on the counterions in solution. In contrast, the effect of ions in the subphase on the dipolar alignment of water is zero. As a result, the capability of monolayer counter-charges to null the effect of dipolar orientation is strongly electrolyte-dependent. Notably, the different effects are additive for mixed charged/zwitterionic lipid systems occurring in nature. Specifically, for an E. coli lipid membrane extract consisting of both zwitterionic and negatively charged lipids, the water orientation can be explained by the sum of the constituents. Our results can be quantitatively reproduced using Gouy-Chapman theory, revealing the relatively straightforward electrostatic effects on the hydration of complex membrane interfaces.
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Affiliation(s)
- Clara-Magdalena Saak
- Faculty of Chemistry, Institute of Physical Chemistry, University of Vienna, Währingerstrasse 42, 1090, Vienna, Austria.
| | - Lisa B Dreier
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
- Graduate School of Materials Science in Mainz, Staudingerweg 9, 55128, Mainz, Germany
| | - Kevin Machel
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
| | - Ellen H G Backus
- Faculty of Chemistry, Institute of Physical Chemistry, University of Vienna, Währingerstrasse 42, 1090, Vienna, Austria.
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128, Mainz, Germany
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8
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Xu D, Yan M, Xie Y. Energy harvesting from water streaming at charged surface. Electrophoresis 2024; 45:244-265. [PMID: 37948329 DOI: 10.1002/elps.202300102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 09/15/2023] [Accepted: 10/26/2023] [Indexed: 11/12/2023]
Abstract
Water flowing at a charged surface may produce electricity, known as streaming current/potentials, which may be traced back to the 19th century. However, due to the low gained power and efficiencies, the energy conversion from streaming current was far from usable. The emergence of micro/nanofluidic technology and nanomaterials significantly increases the power (density) and energy conversion efficiency. In this review, we conclude the fundamentals and recent progress in electrical double layers at the charged surface. We estimate the generated power by hydrodynamic energy dissipation in multi-scaling flows considering the viscous systems with slipping boundary and inertia systems. Then, we review the coupling of volume flow and current flow by the Onsager relation, as well as the figure of merits and efficiency. We summarize the state-of-the-art of electrokinetic energy conversions, including critical performance metrics such as efficiencies, power densities, and generated voltages in various systems. We discuss the advantages and possible constraints by the figure of merits, including single-phase flow and flying droplets.
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Affiliation(s)
- Daxiang Xu
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi'an, P. R. China
| | - Meng Yan
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi'an, P. R. China
| | - Yanbo Xie
- School of Physical Science and Technology, Northwestern Polytechnical University, Xi'an, P. R. China
- School of Aeronautics and Institute of Extreme Mechanics, Northwestern Polytechnical University, Xi'an, P. R. China
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9
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Ryan MJ, Yang N, Kwac K, Wilhelm KB, Chi BK, Weix DJ, Cho M, Zanni MT. The hydrogen-bonding dynamics of water to a nitrile-functionalized electrode is modulated by voltage according to ultrafast 2D IR spectroscopy. Proc Natl Acad Sci U S A 2023; 120:e2314998120. [PMID: 38127983 PMCID: PMC10756189 DOI: 10.1073/pnas.2314998120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 11/15/2023] [Indexed: 12/23/2023] Open
Abstract
We report the hydrogen-bonding dynamics of water to a nitrile-functionalized and plasmonic electrode surface as a function of applied voltage. The surface-enhanced two-dimensional infrared spectra exhibit hydrogen-bonded and non-hydrogen-bonded nitrile features in similar proportions, plus cross peaks between the two. Isotopic dilution experiments show that the cross peaks arise predominantly from chemical exchange between hydrogen-bonded and non-hydrogen-bonded nitriles. The chemical exchange rate depends upon voltage, with the hydrogen bond of the water to the nitriles breaking 2 to 3 times slower (>63 vs. 25 ps) under a positive as compared to a negative potential. Spectral diffusion created by hydrogen-bond fluctuations occurs on a ~1 ps timescale and is moderately potential-dependent. Timescales from molecular dynamics simulations agree qualitatively with the experiment and show that a negative voltage causes a small net displacement of water away from the surface. These results show that the voltage applied to an electrode can alter the timescales of solvent motion at its interface, which has implications for electrochemically driven reactions.
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Affiliation(s)
- Matthew J. Ryan
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Nan Yang
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Kijeong Kwac
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul02841, Republic of Korea
- Department of Chemistry, Korea University, Seoul02841, Republic of Korea
| | - Kiera B. Wilhelm
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Benjamin K. Chi
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Daniel J. Weix
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI53706
| | - Minhaeng Cho
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science, Seoul02841, Republic of Korea
- Department of Chemistry, Korea University, Seoul02841, Republic of Korea
| | - Martin T. Zanni
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI53706
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10
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Gahtori P, Gunwant V, Pandey R. How Does pH Affect the Adsorption of Human Serum Protein in the Presence of Hydrophobic and Hydrophilic Nanoparticles at Air-Water and Lipid-Water Interfaces? LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:15487-15498. [PMID: 37878019 DOI: 10.1021/acs.langmuir.3c01755] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2023]
Abstract
This study investigates interaction between hydrophilic (11-mercaptoundecanoic acid (MUA)) and hydrophobic (1-undecanethiol (UDT)) gold nanoparticles (GNPs) with human serum albumin (HSA) protein on air-water and lipid-water interfaces at pH 3 and 7. Vibrational sum frequency generation (VSFG) spectroscopy is used to analyze changes in the intensity of interfacial water molecules and the C-H group of the protein. At the air-water interface, the hydrophobic interaction between the HSA protein and hydrophobic GNPs at pH 3 leads to their accumulation at the interface, resulting in an increased C-H intensity of the protein with a slight decrease in water intensity. Whereas, at pH 7, where the negative charge of the protein results in the reduced surface activity of the HSA compared to pH 3, the interaction between alkyl chain of the hydrophobic GNPs and alkyl group of the protein results in the adsorption of the protein-capped GNPs at the interface. This leads to an increased intensity of the C-H group of protein and water molecules. However, negatively charged hydrophilic GNPs do not induce significant changes in the interfacial water structure or the C-H group of the protein due to the electrostatic force of repulsion with the negatively charged HSA at pH 7. In contrast, at the lipid-water interface, both hydrophobic and hydrophilic GNPs interact with HSA protein, causing disordering of interfacial water molecules at pH 3 and ordering at pH 7. Interestingly, similar behavior of the protein with both types of GNPs results in comparable ordering/disordering at the interface depending on the pH of solution. Furthermore, the VSFG results obtained with the deuterated lipid suggest that changes in ordering and disorder occur due to increased protein adsorption in the presence of GNPs, causing alterations in the membrane structure. These findings give a better understanding of the mechanisms that govern protein-nanoparticle interaction and their consequential effects on the structure, function, and behavior of molecules at the biological membrane interface, which is crucial for developing safe and effective nanoparticle-based therapeutics.
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Affiliation(s)
- Preeti Gahtori
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
| | - Vineet Gunwant
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
| | - Ravindra Pandey
- Department of Chemistry, Indian Institute of Technology Roorkee, Roorkee 247667, Uttarakhand, India
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11
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Scott HL, Bolmatov D, Premadasa UI, Doughty B, Carrillo JMY, Sacci RL, Lavrentovich M, Katsaras J, Collier CP. Cations Control Lipid Bilayer Memcapacitance Associated with Long-Term Potentiation. ACS APPLIED MATERIALS & INTERFACES 2023; 15:44533-44540. [PMID: 37696028 DOI: 10.1021/acsami.3c09056] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
Phospholipid bilayers can be described as capacitors whose capacitance per unit area (specific capacitance, Cm) is determined by their thickness and dielectric constant─independent of applied voltage. It is also widely assumed that the Cm of membranes can be treated as a "biological constant". Recently, using droplet interface bilayers (DIBs), it was shown that zwitterionic phosphatidylcholine (PC) lipid bilayers can act as voltage-dependent, nonlinear memory capacitors, or memcapacitors. When exposed to an electrical "training" stimulation protocol, capacitive energy storage in lipid membranes was enhanced in the form of long-term potentiation (LTP), which enables biological learning and long-term memory. LTP was the result of membrane restructuring and the progressive asymmetric distribution of ions across the lipid bilayer during training, which is analogous, for example, to exponential capacitive energy harvesting from self-powered nanogenerators. Here, we describe how LTP could be produced from a membrane that is continuously pumped into a nonequilibrium steady state, altering its dielectric properties. During this time, the membrane undergoes static and dynamic changes that are fed back to the system's potential energy, ultimately resulting in a membrane whose modified molecular structure supports long-term memory storage and LTP. We also show that LTP is very sensitive to different salts (KCl, NaCl, LiCl, and TmCl3), with LiCl and TmCl3 having the most profound effect in depressing LTP, relative to KCl. This effect is related to how the different cations interact with the bilayer zwitterionic PC lipid headgroups primarily through electric-field-induced changes to the statistically averaged orientations of water dipoles at the bilayer headgroup interface.
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Affiliation(s)
- Haden L Scott
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Dima Bolmatov
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, United States
- Shull Wollan Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Uvinduni I Premadasa
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jan-Michael Y Carrillo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Robert L Sacci
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Maxim Lavrentovich
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, United States
| | - John Katsaras
- Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
- Department of Physics and Astronomy, The University of Tennessee, Knoxville, Tennessee 37996, United States
- Shull Wollan Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Charles P Collier
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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12
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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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13
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Yu X, Chiang KY, Yu CC, Bonn M, Nagata Y. On the Fresnel factor correction of sum-frequency generation spectra of interfacial water. J Chem Phys 2023; 158:044701. [PMID: 36725499 DOI: 10.1063/5.0133428] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Insights into the microscopic structure of aqueous interfaces are essential for understanding the chemical and physical processes on the water surface, including chemical synthesis, atmospheric chemistry, and events in biomolecular systems. These aqueous interfaces have been probed by heterodyne-detected sum-frequency generation (HD-SFG) spectroscopy. To obtain the molecular response from the measured HD-SFG spectra, one needs to correct the measured ssp spectra for local electromagnetic field effects at the interface due to a spatially varying dielectric function. This so-called Fresnel factor correction can change the inferred response substantially, and different ways of performing this correction lead to different conclusions about the interfacial water response. Here, we compare the simulated and experimental spectra at the air/water interface. We use three previously developed models to compare the experiment with theory: an advanced approach taking into account the detailed inhomogeneous interfacial dielectric profile and the Lorentz and slab models to approximate the interfacial dielectric function. Using the advanced model, we obtain an excellent quantitative agreement between theory and experiment, in both spectral shape and amplitude. Remarkably, we find that for the Fresnel factor correction of the ssp spectra, the Lorentz model for the interfacial dielectric function is equally accurate in the hydrogen (H)-bonded region of the response, while the slab model underestimates this response significantly. The Lorentz model, thus, provides a straightforward method to obtain the molecular response from the measured spectra of aqueous interfaces in the H-bonded region.
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Affiliation(s)
- Xiaoqing Yu
- 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
| | - Chun-Chieh Yu
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - 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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14
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Ober P, Hunger J, Kolbinger SH, Backus EHG, Bonn M. Ion Adsorption and Desorption at the CaF 2 -Water Interface Probed by Flow Experiments and Vibrational Spectroscopy. Angew Chem Int Ed Engl 2022; 61:e202207017. [PMID: 36006393 PMCID: PMC9828343 DOI: 10.1002/anie.202207017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Indexed: 01/12/2023]
Abstract
The dissolution of minerals in contact with water plays a crucial role in geochemistry. However, obtaining molecular insight into interfacial chemistry is challenging. Dissolution typically involves the release of ions from the surface, giving rise to a charged mineral surface. This charge affects the interfacial water arrangement, which can be investigated by surface-specific vibrational Sum Frequency Generation (v-SFG) spectroscopy. For the fluorite-water interface, recent spectroscopic studies concluded that fluoride adsorption/desorption determines the surface charge, which contrasts zeta potential measurements assigning this role to the calcium ion. By combining v-SFG spectroscopy and flow experiments with systematically suppressed dissolution, we uncover the interplay of dominant fluoride and weak calcium adsorption/desorption, resolving the controversy in the literature. We infer the calcium contribution to be orders of magnitude smaller, emphasizing the sensitivity of our approach.
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Affiliation(s)
- Patrick Ober
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
| | - Johannes Hunger
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
| | - Sophia H. Kolbinger
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
| | - Ellen H. G. Backus
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
- University of ViennaFaculty of ChemistryInstitute of Physical ChemistryWaehringer Strasse 421090ViennaAustria
| | - Mischa Bonn
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
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15
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Nanofiltration Treatment of Industrial Wastewater Doped with Organic Dye: A Study of Hydrodynamics and Specific Energy. Processes (Basel) 2022. [DOI: 10.3390/pr10112277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
This study was conducted to eliminate the ions and molecules present in the industrial wastewater received by the municipal wastewater treatment plant (WWTP) of Reghaia, which is located east of Algiers, Algeria. The process was developed for two different study matrices: (a) the wastewater from WWTP and (b) wastewater mixed with Brilliant Blue FCF (BBF) dye to show the influence of the strength of the ionic solution on the treatment. The most effective operating parameters were determined by assessing the residence time distribution applied to the reactor flow regime. Energy analysis showed the viability of a nanofiltration membrane, improving the permeate flux. The nanofiltration process consumed 1.94 kWh/m3 to reduce the chemical oxygen demand (COD) of 63.58% and 48.35% for raw wastewater and doped BBF wastewater, respectively. The results demonstrated that nanofiltration performance with a volume dilution ratio of 1/2 showed the reduction of the COD of 87.2% after 15 min for undoped wastewater, whereas the retention rate decreases to 64% with an increase of dilution ratio to 4/5 for the same water matrix. The influence of a pH of 5 has a significant influence on the composition of the wastewater matrix by the reduction of COD of 49.8% and 59.68% for doped wastewater and raw wastewater, respectively. This could be explained by the isolated points of the membrane in the order of 4.5.
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16
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Sloutskin E, Tamam L, Sapir Z, Ocko BM, Bain CD, Kuzmenko I, Gog T, Deutsch M. Counterions under a Surface-Adsorbed Cationic Surfactant Monolayer: Structure and Thermodynamics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:12356-12366. [PMID: 36170153 DOI: 10.1021/acs.langmuir.2c02076] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The surface adsorption of ionic surfactants is fundamental for many widespread phenomena in life sciences and for a wide range of technological applications. However, direct atomic-resolution structural experimental studies of noncrystalline surface-adsorbed films are scarce. Thus, even the most central physical aspects of these films, such as their charge density, remain uncertain. Consequently, theoretical models based on contradicting assumptions as for the surface films' ionization are widely used for the description and prediction of surface thermodynamics. We employ X-ray reflectivity to obtain the Ångström-scale surface-normal structure of surface-adsorbed films of the cationic surfactant cetyltrimethylammonium bromide (CTAB) in aqueous solutions at several different temperatures and concentrations. In conjunction with published neutron reflectivity data, we determine the surface-normal charge distribution due to the dissociated surfactants' headgroups. The distribution appears to be inconsistent with the Gouy-Chapman model yet consistent with a compact Stern layer model of condensed counterions. The experimental surfactant adsorption thermodynamics conforms well to classical, Langmuir and Kralchevsky, adsorption models. Furthermore, the Kralchevsky model correctly reproduces the observed condensation of counterions, allowing the values of the adsorption parameters to be resolved, based on the combination of the present data and the published surface tension measurements.
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Affiliation(s)
- Eli Sloutskin
- Physics Department and Bar-Ilan Institute of Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Lilach Tamam
- Physics Department and Bar-Ilan Institute of Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Zvi Sapir
- Physics Department and Bar-Ilan Institute of Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Benjamin M Ocko
- National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, New York 11973, United States
| | - Colin D Bain
- Department of Chemistry, Durham University, South Road, Durham DH1 3LE, U.K
| | - Ivan Kuzmenko
- Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Thomas Gog
- Advanced Photon Source, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Moshe Deutsch
- Physics Department and Bar-Ilan Institute of Nanotechnology & Advanced Materials, Bar-Ilan University, Ramat-Gan 5290002, Israel
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17
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Luo Y, Pang AP, Lu X. Liquid-Solid Interfaces under Dynamic Shear Flow: Recent Insights into the Interfacial Slip. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2022; 38:4473-4482. [PMID: 35377658 DOI: 10.1021/acs.langmuir.2c00037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The development of micro/nanofluidic techniques has recently revived interest in dynamic shear flow at liquid-solid interfaces. When the nature of the liquid-solid boundaries was revisited, the slip of the fluids relative to the solid wall was predicted theoretically and confirmed experimentally. This indicates that the molecular-level structures of the liquid-solid interfaces will be influenced by the liquid flow over certain temporal and spatial criteria. However, the fluid flow at the boundary layer still cannot be precisely predicted and effectively controlled, somehow limiting its practical applications. Here, we summarize the recent advances for the microscopic structures at the liquid-solid interfaces upon shear flow. Special attention was given to a second-order nonlinear optical technique, sum frequency generation vibrational spectroscopy, which is a powerful tool for exploring the molecular-level structures and structural dynamics at the liquid-solid interfaces and offering new insights into the molecular mechanisms of the fluid slip at the interfaces. Moreover, we discuss the possible approaches for controlling the interfacial slip at the molecular level and highlight the current challenges and opportunities. Although the theoretical framework of the slip at the liquid-solid interfaces is still incomplete, we hope that this Perspective will complement and enhance our understanding of various interfacial properties and phenomena with respect to practical non-equilibrium dynamic processes happening at the interfaces.
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Affiliation(s)
- Yongsheng Luo
- The State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu, P. R. China
| | - Ai-Ping Pang
- The State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu, P. R. China
| | - Xiaolin Lu
- The State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu, P. R. China
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18
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Sthoer AA, Tyrode EC. Anion Specific Effects at Negatively Charged Interfaces: Influence of Cl -, Br -, I -, and SCN - on the Interactions of Na + with the Carboxylic Acid Moiety. J Phys Chem B 2021; 125:12384-12391. [PMID: 34705447 PMCID: PMC8591606 DOI: 10.1021/acs.jpcb.1c07758] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Revised: 10/10/2021] [Indexed: 11/30/2022]
Abstract
Unlike counterion interactions with charged interfaces, the influence of co-ions is only scarcely reported in the literature. In this work, the effect of SCN- and the halide co-ions in the interactions of Na+ with carboxylic acid Langmuir monolayers is investigated by using vibrational sum frequency spectroscopy. At 1 M concentrations in the subphase, the identity of the anion is shown to have a remarkable influence on the charging behavior and degree of deprotonation of the monolayer, with ions ordering in the sequence I- > SCN- > Cl- ≈ Br-. The same trend is observed at both pH 6 and pH 9 when the monolayer is intrinsically more charged. Spectroscopic evidence is found for both the presence of I- and SCN- in the interfacial region at levels close to their detection limits. The results contradict electrostatic theories on charged interfaces where co-ions are not expected to play any significant role. The higher propensity for the large polarizable anions to deprotonate the monolayer is explained in terms of their ability to modify the cations affinity toward the carboxylic acid groups present at the surface.
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Affiliation(s)
- Adrien
P. A. Sthoer
- Department of Chemistry, KTH, Dröttning Kristinas väg 51, SE-10044 Stockholm, Sweden
| | - Eric C. Tyrode
- Department of Chemistry, KTH, Dröttning Kristinas väg 51, SE-10044 Stockholm, Sweden
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19
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Huang H, Zhang C, Crisci R, Lu T, Hung HC, Sajib MSJ, Sarker P, Ma J, Wei T, Jiang S, Chen Z. Strong Surface Hydration and Salt Resistant Mechanism of a New Nonfouling Zwitterionic Polymer Based on Protein Stabilizer TMAO. J Am Chem Soc 2021; 143:16786-16795. [PMID: 34582683 DOI: 10.1021/jacs.1c08280] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Zwitterionic polymers exhibit excellent nonfouling performance due to their strong surface hydrations. However, salt molecules may severely reduce the surface hydrations of typical zwitterionic polymers, making the application of these polymers in real biological and marine environments challenging. Recently, a new zwitterionic polymer brush based on the protein stabilizer trimethylamine N-oxide (TMAO) was developed as an outstanding nonfouling material. Using surface-sensitive sum frequency generation (SFG) vibrational spectroscopy, we investigated the surface hydration of TMAO polymer brushes (pTMAO) and the effects of salts and proteins on such surface hydration. It was discovered that exposure to highly concentrated salt solutions such as seawater only moderately reduced surface hydration. This superior resistance to salt effects compared to other zwitterionic polymers is due to the shorter distance between the positively and negatively charged groups, thus a smaller dipole in pTMAO and strong hydration around TMAO zwitterion. This results in strong bonding interactions between the O- in pTMAO and water, and weaker interaction between O- and metal cations due to the strong repulsion from the N+ and hydration water. Computer simulations at quantum and atomistic scales were performed to support SFG analyses. In addition to the salt effect, it was discovered that exposure to proteins in seawater exerted minimal influence on the pTMAO surface hydration, indicating complete exclusion of protein attachment. The excellent nonfouling performance of pTMAO originates from its extremely strong surface hydration that exhibits effective resistance to disruptions induced by salts and proteins.
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Affiliation(s)
| | | | | | | | - Hsiang-Chieh Hung
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Md Symon Jahan Sajib
- Department of Chemical Engineering, Howard University, Washington D.C. 20059, United States
| | - Pranab Sarker
- Department of Chemical Engineering, Howard University, Washington D.C. 20059, United States
| | - Jinrong Ma
- Department of Chemical Engineering, University of Washington, Seattle, Washington 98195, United States
| | - Tao Wei
- Department of Chemical Engineering, Howard University, Washington D.C. 20059, United States
| | - Shaoyi Jiang
- Meinig School of Biomedical Engineering, Cornell University, Ithaca, New York 14853, United States
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20
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Gera R, Bakker HJ, Franklin-Mergarejo R, Morzan UN, Falciani G, Bergamasco L, Versluis J, Sen I, Dante S, Chiavazzo E, Hassanali AA. Emergence of Electric Fields at the Water-C12E6 Surfactant Interface. J Am Chem Soc 2021; 143:15103-15112. [PMID: 34498857 DOI: 10.1021/jacs.1c05112] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We study the properties of the interface of water and the surfactant hexaethylene glycol monododecyl ether (C12E6) with a combination of heterodyne-detected vibrational sum frequency generation (HD-VSFG), Kelvin-probe measurements, and molecular dynamics (MD) simulations. We observe that the addition of the hydrogen-bonding surfactant C12E6, close to the critical micelle concentration (CMC), induces a drastic enhancement in the hydrogen bond strength of the water molecules close to the interface, as well as a flip in their net orientation. The mutual orientation of the water and C12E6 molecules leads to the emergence of a broad (∼3 nm) interface with a large electric field of ∼1 V/nm, as evidenced by the Kelvin-probe measurements and MD simulations. Our findings may open the door for the design of novel electric-field-tuned catalytic and light-harvesting systems anchored at the water-surfactant-air interface.
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Affiliation(s)
- Rahul Gera
- AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Huib J Bakker
- AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | | | - Uriel N Morzan
- International Centre for Theoretical Physics, Strada Costiera 11, 34151 Trieste, Italy
| | - Gabriele Falciani
- Energy Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, Italy
| | - Luca Bergamasco
- Energy Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, Italy
| | - Jan Versluis
- AMOLF, Science Park 104, 1098 XG Amsterdam, The Netherlands
| | - Indraneel Sen
- Uppsala University, Laegerhyddsvaegen 1, 751 20 Uppsala, Sweden
| | - Silvia Dante
- Materials Characterization Facility, Italian Institute of Technology, 16163 Genoa, Italy
| | - Eliodoro Chiavazzo
- Energy Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, Torino 10129, Italy
| | - Ali A Hassanali
- International Centre for Theoretical Physics, Strada Costiera 11, 34151 Trieste, Italy
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21
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Moll CJ, Versluis J, Bakker HJ. Direct Evidence for a Surface and Bulk Specific Response in the Sum-Frequency Generation Spectrum of the Water Bend Vibration. PHYSICAL REVIEW LETTERS 2021; 127:116001. [PMID: 34558941 DOI: 10.1103/physrevlett.127.116001] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 08/02/2021] [Accepted: 08/06/2021] [Indexed: 05/19/2023]
Abstract
We study the bending mode of pure water and charged aqueous surfaces using heterodyne-detected vibrational sum-frequency generation spectroscopy. We observe a low (1626 cm^{-1}) and a high (1656 cm^{-1}) frequency component that can be unambiguously assigned to an interfacial dipole and a bulk quadrupolar response, respectively. We thus demonstrate that probing the bending mode provides structural and quantitative information on both the surface and the bulk.
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Affiliation(s)
- C J Moll
- AMOLF, Ultrafast Spectroscopy, Science Park 104, 1098XG Amsterdam, Netherlands
| | - J Versluis
- AMOLF, Ultrafast Spectroscopy, Science Park 104, 1098XG Amsterdam, Netherlands
| | - H J Bakker
- AMOLF, Ultrafast Spectroscopy, Science Park 104, 1098XG Amsterdam, Netherlands
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22
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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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23
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Luo Y, Wang C, Pang AP, Zhang X, Wang D, Lu X. Low-Concentration Salt Solution Changes the Interfacial Molecular Behavior of Polyelectrolyte Brushes. Macromolecules 2021. [DOI: 10.1021/acs.macromol.1c00119] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Yongsheng Luo
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Chu Wang
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Ai-Ping Pang
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
| | - Xiang Zhang
- National Center for International Joint Research of Micro−Nano Molding Technology, School of Mechanics & Engineering Science, Zhengzhou University, Zhengzhou 450001, P. R. China
| | - Dayang Wang
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, Jilin Province, P. R. China
| | - Xiaolin Lu
- State Key Laboratory of Bioelectronics, School of Biological Science & Medical Engineering, Southeast University, Nanjing 210096, Jiangsu Province, P. R. China
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24
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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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25
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Ura D, Knapczyk-Korczak J, Szewczyk PK, Sroczyk EA, Busolo T, Marzec MM, Bernasik A, Kar-Narayan S, Stachewicz U. Surface Potential Driven Water Harvesting from Fog. ACS NANO 2021; 15:8848-8859. [PMID: 33900735 PMCID: PMC8158858 DOI: 10.1021/acsnano.1c01437] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/02/2021] [Indexed: 05/08/2023]
Abstract
Access to clean water is a global challenge, and fog collectors are a promising solution. Polycarbonate (PC) fibers have been used in fog collectors but with limited efficiency. In this study, we show that controlling voltage polarity and humidity during the electrospinning of PC fibers improves their surface properties for water collection capability. We experimentally measured the effect of both the surface morphology and the chemistry of PC fiber on their surface potential and mechanical properties in relation to the water collection efficiency from fog. PC fibers produced at high humidity and with negative voltage polarity show a superior water collection rate combined with the highest tensile strength. We proved that electric potential on surface and morphology are crucial, as often designed by nature, for enhancing the water collection capabilities via the single-step production of fibers without any postprocessing needs.
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Affiliation(s)
- Daniel
P. Ura
- Faculty
of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Joanna Knapczyk-Korczak
- Faculty
of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Piotr K. Szewczyk
- Faculty
of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Ewa A. Sroczyk
- Faculty
of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Tommaso Busolo
- Department
of Materials Science and Metallurgy, University
of Cambridge, CB3 0FS Cambridge, United Kingdom
| | - Mateusz M. Marzec
- Academic
Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Andrzej Bernasik
- Academic
Centre for Materials and Nanotechnology, AGH University of Science and Technology, 30-059 Kraków, Poland
- Faculty
of Physics and Applied Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland
| | - Sohini Kar-Narayan
- Department
of Materials Science and Metallurgy, University
of Cambridge, CB3 0FS Cambridge, United Kingdom
| | - Urszula Stachewicz
- Faculty
of Metals Engineering and Industrial Computer Science, AGH University of Science and Technology, 30-059 Kraków, Poland
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26
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Sakakibara N, Inoue K, Takahashi S, Goto T, Ito T, Akada K, Miyawaki J, Hakuta Y, Terashima K, Harada Y. Soft X-ray emission spectroscopy for the electronic state of water molecules influenced by plasma-treated multi-walled carbon nanotubes. Phys Chem Chem Phys 2021; 23:10468-10474. [PMID: 33890957 DOI: 10.1039/d0cp05990k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
In this study, soft X-ray emission spectroscopy of an aqueous colloidal dispersion of multi-walled carbon nanotubes modified via the plasma process in an aqueous solution was performed for investigating the electronic state of water molecules on the colloidal particles. In the aqueous dispersion, reconstruction of the hydrogen-bonded network was implied by the O 1s spectral changes in the 1b1' and 1b1'' peaks. Furthermore, the O 1s spectral intensity around the 3a1 state was enhanced to an unusually broad energy range in comparison with previous studies. This unusual spectral change might be attributed to the hybridization of the electronic states of oxygen-containing functional groups on the surface of the plasma-modified multi-walled carbon nanotubes and that of the surrounding water molecules. Our observation indicates not only reconstruction of the hydrogen-bonded network in the aqueous dispersion but also a significant interaction of the electronic states between the water molecules and the plasma-modified multi-walled carbon nanotubes.
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Affiliation(s)
- Noritaka Sakakibara
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan. and AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8589, Japan
| | - Kenichi Inoue
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan. and AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8589, Japan
| | - Shion Takahashi
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan.
| | - Taku Goto
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan. and AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8589, Japan
| | - Tsuyohito Ito
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan. and AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8589, Japan
| | - Keishi Akada
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan and Synchrotron Radiation Research Organization, The University of Tokyo, 1-1-1 Koto, Sayo, Hyogo 679-5148, Japan.
| | - Jun Miyawaki
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan. and Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan and Synchrotron Radiation Research Organization, The University of Tokyo, 1-1-1 Koto, Sayo, Hyogo 679-5148, Japan.
| | - Yukiya Hakuta
- AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8589, Japan
| | - Kazuo Terashima
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan. and AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8589, Japan
| | - Yoshihisa Harada
- Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan. and AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8589, Japan and Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan and Synchrotron Radiation Research Organization, The University of Tokyo, 1-1-1 Koto, Sayo, Hyogo 679-5148, Japan.
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27
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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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28
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Krem S, Lee M, Sam S, Sung W, Kim D. Structure of Electric Double Layer under Cationic Langmuir Monolayer: Charge Condensation Effect. J Phys Chem Lett 2021; 12:3417-3423. [PMID: 33789054 DOI: 10.1021/acs.jpclett.1c00401] [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
Langmuir monolayers consisting of mixtures of 1-hexadecanol (HD) and 1,2-dipalmitoyl-3-trimethylammonium-propane (DPTAP) (having quaternary amine headgroup) at different molar ratios were prepared to investigate the effect of the surface charge density on the structure of an electric double layer. The fatty alcohol molecules worked as passive spacers to widen the distance between the amine groups in the monolayer, to vary the surface charge density of the monolayer, and these mixture monolayer systems were probed by surface-sensitive sum-frequency vibrational spectroscopy. A strong sum-frequency signal in the OH range for a pure DPTAP monolayer (with a surface charge density of ∼0.4 C/m2) hardly decreased as the surface charge density was reduced up to ∼0.12 C/m2 (1 e per 140 Å2) and afterward decreased monotonically as more HD occupied the monolayer. The Gouy-Chapman theory incorporating a charged-condensed layer in which the counterion concentration is limited by a close packing of the counterions could account for the above saturation behavior in the sum-frequency spectra.
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Affiliation(s)
- Sona Krem
- Department of Physics, Sogang University, Seoul, Korea
| | - Minho Lee
- Department of Physics, Sogang University, Seoul, Korea
| | - Sokhuoy Sam
- Department of Physics, Sogang University, Seoul, Korea
| | - Woongmo Sung
- Department of Physics, Sogang University, Seoul, Korea
| | - Doseok Kim
- Department of Physics, Sogang University, Seoul, Korea
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29
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Neal JF, Saha A, Zerkle MM, Zhao W, Rogers MM, Flood AH, Allen HC. Molecular Recognition and Hydration Energy Mismatch Combine To Inform Ion Binding Selectivity at Aqueous Interfaces. J Phys Chem A 2020; 124:10171-10180. [DOI: 10.1021/acs.jpca.0c09568] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Jennifer F. Neal
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Ankur Saha
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Mia M. Zerkle
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Wei Zhao
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Mickey M. Rogers
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Amar H. Flood
- Department of Chemistry, Indiana University, Bloomington, Indiana 47405, United States
| | - Heather C. Allen
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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30
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Frias MA, Disalvo EA. Breakdown of classical paradigms in relation to membrane structure and functions. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1863:183512. [PMID: 33202248 DOI: 10.1016/j.bbamem.2020.183512] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Revised: 11/11/2020] [Accepted: 11/12/2020] [Indexed: 01/10/2023]
Abstract
Updates of the mosaic fluid membrane model implicitly sustain the paradigms that bilayers are closed systems conserving a state of fluidity and behaving as a dielectric slab. All of them are a consequence of disregarding water as part of the membrane structure and its essential role in the thermodynamics and kinetics of membrane response to bioeffectors. A correlation of the thermodynamic properties with the structural features of water makes possible to introduce the lipid membrane as a responsive structure due to the relaxation of water rearrangements in the kinetics of bioeffectors' interactions. This analysis concludes that the lipid membranes are open systems and, according to thermodynamic of irreversible formalism, bilayers and monolayers can be reasonable compared under controlled conditions. The inclusion of water in the complex structure makes feasible to reconsider the concept of dielectric slab and fluidity.
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Affiliation(s)
- M A Frias
- Applied Biophysics and Food Research Center, CIBAAL-UNSE-CONICET, Santiago del Estero, Argentina
| | - E A Disalvo
- Applied Biophysics and Food Research Center, CIBAAL-UNSE-CONICET, Santiago del Estero, Argentina.
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31
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Liang D, Dahal U, Zhang YK, Lochbaum C, Ray D, Hamers RJ, Pedersen JA, Cui Q. Interfacial water and ion distribution determine ζ potential and binding affinity of nanoparticles to biomolecules. NANOSCALE 2020; 12:18106-18123. [PMID: 32852025 DOI: 10.1039/d0nr03792c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The molecular features that dictate interactions between functionalized nanoparticles and biomolecules are not well understood. This is in part because for highly charged nanoparticles in solution, establishing a clear connection between the molecular features of surface ligands and common experimental observables such as ζ potential requires going beyond the classical models based on continuum and mean field models. Motivated by these considerations, molecular dynamics simulations are used to probe the electrostatic properties of functionalized gold nanoparticles and their interaction with a charged peptide in salt solutions. Counterions are observed to screen the bare ligand charge to a significant degree even at the moderate salt concentration of 50 mM. As a result, the apparent charge density and ζ potential are largely insensitive to the bare ligand charge densities, which fall in the range of ligand densities typically measured experimentally for gold nanoparticles. While this screening effect was predicted by classical models such as the Manning condensation theory, the magnitudes of the apparent surface charge from microscopic simulations and mean-field models are significantly different. Moreover, our simulations found that the chemical features of the surface ligand (e.g., primary vs. quaternary amines, heterogeneous ligand lengths) modulate the interfacial ion and water distributions and therefore the interfacial potential. The importance of interfacial water is further highlighted by the observation that introducing a fraction of hydrophobic ligands enhances the strength of electrostatic binding of the charged peptide. Finally, the simulations highlight that the electric double layer is perturbed upon binding interactions. As a result, it is the bare charge density rather than the apparent charge density or ζ potential that better correlates with binding affinity of the nanoparticle to a charged peptide. Overall, our study highlights the importance of molecular features of the nanoparticle/water interface and underscores a set of design rules for the modulation of electrostatic driven interactions at nano/bio interfaces.
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Affiliation(s)
- Dongyue Liang
- Department of Chemistry, University of Wisconsin-Madison, 1101 University Avenue, Madison, WI 53706, USA
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32
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De Mel JU, Gupta S, Perera RM, Ngo L, Zolnierczuk P, Bleuel M, Pingali SV, Schneider GJ. Influence of External NaCl Salt on Membrane Rigidity of Neutral DOPC Vesicles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:9356-9367. [PMID: 32672981 DOI: 10.1021/acs.langmuir.0c01004] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Sodium chloride (NaCl) is a very common molecule in biotic and abiotic aqueous environments. In both cases, variation of ionic strength is inevitable. In addition to the osmotic variation posed by such perturbations, the question of whether the interactions of monovalent ions Na+ and Cl-, especially with the neutral head groups of phospholipid membranes are impactful enough to change the membrane rigidity, is still not entirely understood. We investigated the dynamics of 1,2-di-(octadecenoyl)-sn-glycero-3-phosphocholine (DOPC) vesicles with zwitterionic neutral head groups in the fluid phase with increasing external salt concentration. At higher salt concentrations, we observe an increase in bending rigidity from neutron spin echo (NSE) spectroscopy and an increase in bilayer thickness from small-angle X-ray scattering (SAXS). We compared different models to distinguish membrane undulations, lipid tail motions, and the translational diffusion of the vesicles. All of the models indicate an increase in bending rigidity by a factor of 1.3-3.6. We demonstrate that even down to t > 10 ns and for Q > 0.07 Å-1, the observed NSE relaxation spectra are influenced by translational diffusion of the vesicles. For t < 5 ns, the lipid tail motion dominates the intermediate dynamic structure factor. As the salt concentration increases, this contribution diminishes. We introduced a time-dependent analysis for the bending rigidity that highlights only a limited Zilman-Granek time window in which the rigidity is physically meaningful.
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Affiliation(s)
- Judith U De Mel
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Sudipta Gupta
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Rasangi M Perera
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Ly Ngo
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Piotr Zolnierczuk
- Jülich Centre for Neutron Science (JCNS), Outstation at SNS, POB 2008, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Markus Bleuel
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8562, United States
| | - Sai Venkatesh Pingali
- Neutron Sciences Directorate, Oak Ridge National Laboratory (ORNL), POB 2008, 1 Bethel Valley Road, Oak Ridge, Tennessee 37831, United States
| | - Gerald J Schneider
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
- Department of Physics & Astronomy, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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33
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Chowdhury AU, Lin L, Doughty B. Hydrogen-Bond-Driven Chemical Separations: Elucidating the Interfacial Steps of Self-Assembly in Solvent Extraction. ACS APPLIED MATERIALS & INTERFACES 2020; 12:32119-32130. [PMID: 32551500 DOI: 10.1021/acsami.0c06176] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Chemical separations, particularly liquid extractions, are pervasive in academic and industrial laboratories, yet a mechanistic understanding of the events governing their function are obscured by interfacial phenomena that are notoriously difficult to measure. In this work, we investigate the fundamental steps of ligand self-assembly as driven by changes in the interfacial H-bonding network using vibrational sum frequency generation. Our results show how the bulk pH modulates the interfacial structure of extractants at the buried oil/aqueous interface via the formation of unique H-bonding networks that order and bridge ligands to produce self-assembled aggregates. These extended H-bonded structures are key to the subsequent extraction of Co2+ from the aqueous phase in promoting micelle formation and subsequent ejection of the said micelle into the oil phase. The combination of static and time-resolved measurements reveals the events underlying complexities of liquid extractions at high [Co2+]:[ligand] ratios by showing an evolution of interfacially assembled structures that are readily tuned on a chemical basis by altering the compositions of the aqueous phase. The results of this work point to new principles to design-applied separations through the manipulation of surface charge, electrostatic screening, and the associated H-bonding networks that arise at the interface to facilitate organization and subsequent extraction.
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Affiliation(s)
- Azhad U Chowdhury
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Lu Lin
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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34
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Dalstein L, Huang JR, Wen YC. Wavelength-scanning second-harmonic generation for determining absolute charge density at aqueous interfaces. OPTICS LETTERS 2020; 45:3733-3736. [PMID: 32630941 DOI: 10.1364/ol.396002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 05/31/2020] [Indexed: 06/11/2023]
Abstract
We develop a new, to the best of our knowledge, optical scheme based on second-harmonic generation (SHG) at multiple wavelengths for unequivocal separation of the second-order and the electric-field-induced third-order nonlinear optical contributions from aqueous interfaces. The third-order SHG originating from the field-induced reorientation order of water molecules in the electrical double layer offers an optical label-free and inherent probe to the surface charge density and surface potential in the absolute scales. We verify this wavelength-scanning SHG scheme both theoretically and experimentally, and show that the approach is applicable to water interfaces with bulk ionic strength below 500 µM and can achieve a detection sensitivity for a surface charge density of ∼10-4C/m2.
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35
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Zhang Y, Hudson-Smith NV, Frand SD, Cahill MS, Davis LS, Feng ZV, Haynes CL, Hamers RJ. Influence of the Spatial Distribution of Cationic Functional Groups at Nanoparticle Surfaces on Bacterial Viability and Membrane Interactions. J Am Chem Soc 2020; 142:10814-10823. [PMID: 32402194 DOI: 10.1021/jacs.0c02737] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
While positively charged nanomaterials induce cytotoxicity in many organisms, much less is known about how the spatial distribution and presentation of molecular surface charge impact nanoparticle-biological interactions. We systematically functionalized diamond nanoparticle surfaces with five different cationic surface molecules having different molecular structures and conformations, including four small ligands and one polymer, and we then probed the molecular-level interaction between these nanoparticles and bacterial cells. Shewanella oneidensis MR-1 was used as a model bacterial cell system to investigate how the molecular length and conformation of cationic surface charges influence their interactions with the Gram-negative bacterial membranes. Nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) demonstrate the covalent modification of the nanoparticle surface with the desired cationic organic monolayers. Surprisingly, bacterial growth-based viability (GBV) and membrane damage assays both show only minimal biological impact by the NPs functionalized with short cationic ligands within the concentration range tested, yet NPs covalently linked to a cationic polymer induce strong cytotoxicity, including reduced cellular viability and significant membrane damage at the same concentration of cationic groups. Transmission electron microscopy (TEM) images of these NP-exposed bacterial cells show that NPs functionalized with cationic polymers induce significant membrane distortion and the production of outer membrane vesicle-like features, while NPs bearing short cationic ligands only exhibit weak membrane association. Our results demonstrate that the spatial distribution of molecular charge plays a key role in controlling the interaction of cationic nanoparticles with bacterial cell membranes and the subsequent biological impact. Nanoparticles functionalized with ligands having different lengths and conformations can have large differences in interactions even while having nearly identical zeta potentials. While the zeta potential is a convenient and commonly used measure of nanoparticle charge, it does not capture essential differences in molecular-level nanoparticle properties that control their biological impact.
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Affiliation(s)
- Yongqian Zhang
- University of Wisconsin-Madison, Department of Chemistry, Madison, Wisconsin 53706, United States
| | - Natalie V Hudson-Smith
- University of Minnesota Twin Cities, Department of Chemistry, Minneapolis, Minnesota 55455, United States
| | - Seth D Frand
- Augsburg University, Department of Chemistry, Minneapolis, Minnesota 55454, United States
| | - Meghan S Cahill
- University of Minnesota Twin Cities, Department of Chemistry, Minneapolis, Minnesota 55455, United States
| | - Larissa S Davis
- University of Wisconsin-Madison, Department of Chemistry, Madison, Wisconsin 53706, United States
| | - Z Vivian Feng
- Augsburg University, Department of Chemistry, Minneapolis, Minnesota 55454, United States
| | - Christy L Haynes
- University of Minnesota Twin Cities, Department of Chemistry, Minneapolis, Minnesota 55455, United States
| | - Robert J Hamers
- University of Wisconsin-Madison, Department of Chemistry, Madison, Wisconsin 53706, United States
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36
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Xiong H, Devegowda D, Huang L. Oil–water
transport in
clay‐hosted
nanopores: Effects of
long‐range
electrostatic forces. AIChE J 2020. [DOI: 10.1002/aic.16276] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Hao Xiong
- Mewbourne School of Petroleum and Geological EngineeringThe University of Oklahoma Norman Oklahoma USA
| | - Deepak Devegowda
- Mewbourne School of Petroleum and Geological EngineeringThe University of Oklahoma Norman Oklahoma USA
| | - Liangliang Huang
- Chemical, Biological & Materials EngineeringThe University of Oklahoma Norman Oklahoma USA
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37
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Gschwend GC, Olaya A, Girault HH. How to polarise an interface with ions: the discrete Helmholtz model. Chem Sci 2020; 11:10807-10813. [PMID: 34094335 PMCID: PMC8162426 DOI: 10.1039/d0sc00685h] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Accepted: 05/16/2020] [Indexed: 11/21/2022] Open
Abstract
The distribution of electrolytes in an electric field usually relies on theories based on the Poisson-Boltzmann formalism. These models predict that, in the case of a metallic electrode, ionic charges screen the electrode potential, leading to concentration-dependent ion distributions. This theoretical framework was first applied at solid-liquid interfaces and then transposed to soft interfaces. However, in this latter case, the potential in which the electrolytes evolve is not homogeneous, which is less amenable to a mean-field description. In this report, we show that at polarised soft interfaces the potential difference takes place between two closely interacting ionic monolayers. In this configuration, ions of opposite charges directly neutralise each other leading to an absence of diffuse layers and charge screening by surrounding ions. Thus, independently of the electrolyte concentrations, the surface charge density is a linear function of the potential difference, which results in a constant capacitance.
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Affiliation(s)
- Grégoire C Gschwend
- Laboratoire d'Electrochimie Physique et Analytique (LEPA), École Polytechnique Fédérale de Lausanne (EPFL) Rue de l'Industrie 17 CH-1951 Sion Switzerland
| | - Astrid Olaya
- Laboratoire d'Electrochimie Physique et Analytique (LEPA), École Polytechnique Fédérale de Lausanne (EPFL) Rue de l'Industrie 17 CH-1951 Sion Switzerland
| | - Hubert H Girault
- Laboratoire d'Electrochimie Physique et Analytique (LEPA), École Polytechnique Fédérale de Lausanne (EPFL) Rue de l'Industrie 17 CH-1951 Sion Switzerland
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38
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Seki T, Yu CC, Yu X, Ohto T, Sun S, Meister K, Backus EHG, Bonn M, Nagata Y. Decoding the molecular water structure at complex interfaces through surface-specific spectroscopy of the water bending mode. Phys Chem Chem Phys 2020; 22:10934-10940. [PMID: 32373844 DOI: 10.1039/d0cp01269f] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The structure of interfacial water determines atmospheric chemistry, wetting properties of materials, and protein folding. The challenge of investigating the properties of specific interfacial water molecules has frequently been confronted using surface-specific sum-frequency generation (SFG) vibrational spectroscopy using the O-H stretch mode. While perfectly suited for the water-air interface, for complex interfaces, a potential complication arises from the contribution of hydroxyl or amine groups of non-water species present at the surface, such as surface hydroxyls on minerals, or O-H and N-H groups contained in proteins. Here, we present a protocol to extract the hydrogen bond strength selectively of interfacial water, through the water bending mode. The bending mode vibrational frequency distribution provides a new avenue for unveiling the hydrogen bonding structure of interfacial water at complex aqueous interfaces. We demonstrate this method for the water-CaF2 and water-protein interfaces. For the former, we show that this method can indeed single out water O-H groups from surface hydroxyls, and that with increasing pH, the hydrogen-bonded network of interfacial water strengthens. Furthermore, we unveil enhanced hydrogen bonding of water, compared to bulk water, at the interface with human serum albumin proteins, a prototypical bio-interface.
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Affiliation(s)
- Takakazu Seki
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
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39
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Tang F, Ohto T, Sun S, Rouxel JR, Imoto S, Backus EHG, Mukamel S, Bonn M, Nagata Y. Molecular Structure and Modeling of Water-Air and Ice-Air Interfaces Monitored by Sum-Frequency Generation. Chem Rev 2020; 120:3633-3667. [PMID: 32141737 PMCID: PMC7181271 DOI: 10.1021/acs.chemrev.9b00512] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Indexed: 12/26/2022]
Abstract
From a glass of water to glaciers in Antarctica, water-air and ice-air interfaces are abundant on Earth. Molecular-level structure and dynamics at these interfaces are key for understanding many chemical/physical/atmospheric processes including the slipperiness of ice surfaces, the surface tension of water, and evaporation/sublimation of water. Sum-frequency generation (SFG) spectroscopy is a powerful tool to probe the molecular-level structure of these interfaces because SFG can specifically probe the topmost interfacial water molecules separately from the bulk and is sensitive to molecular conformation. Nevertheless, experimental SFG has several limitations. For example, SFG cannot provide information on the depth of the interface and how the orientation of the molecules varies with distance from the surface. By combining the SFG spectroscopy with simulation techniques, one can directly compare the experimental data with the simulated SFG spectra, allowing us to unveil the molecular-level structure of water-air and ice-air interfaces. Here, we present an overview of the different simulation protocols available for SFG spectra calculations. We systematically compare the SFG spectra computed with different approaches, revealing the advantages and disadvantages of the different methods. Furthermore, we account for the findings through combined SFG experiments and simulations and provide future challenges for SFG experiments and simulations at different aqueous interfaces.
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Affiliation(s)
- Fujie Tang
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Tatsuhiko Ohto
- Graduate
School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Shumei Sun
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physical Chemistry, University of Vienna, Währinger Strasse 42, 1090 Vienna, Austria
| | - Jérémy R. Rouxel
- Department
of Chemistry and Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Sho Imoto
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Ellen H. G. Backus
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physical Chemistry, University of Vienna, Währinger Strasse 42, 1090 Vienna, Austria
| | - Shaul Mukamel
- Department
of Chemistry and Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Mischa Bonn
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Yuki Nagata
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physics, State Key Laboratory of Surface Physics and Key Laboratory
of Micro- and Nano-Photonic Structures (MOE), Fudan University, Shanghai 200433, China
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40
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Oh MI, Oh CI, Weaver DF. Effect of Cholesterol on the Structure of Networked Water at the Surface of a Model Lipid Membrane. J Phys Chem B 2020; 124:3686-3694. [DOI: 10.1021/acs.jpcb.0c01889] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- Myong In Oh
- Krembil Research Institute, University Health Network, Toronto, Ontario M5T 0S8, Canada
| | - Chang In Oh
- Department of Mathematics, University of Western Ontario, London, Ontario, N6A 5B7, Canada
| | - Donald F. Weaver
- Krembil Research Institute, University Health Network, Toronto, Ontario M5T 0S8, Canada
- Department of Chemistry, University of Toronto, Toronto, Ontario M5S 3H6, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario M5G 2C4, Canada
- Department of Pharmaceutical Sciences, University of Toronto, Toronto, Ontario M5S 3M2, Canada
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41
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Takahashi T, Harada R, Shigeta Y. Distribution of Counter Ions in Negatively-charged Lipid/Water/Air Interface: Molecular Dynamics Study. CHEM LETT 2020. [DOI: 10.1246/cl.200043] [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)
- Teruyuki Takahashi
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| | - Ryuhei Harada
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
| | - Yasuteru Shigeta
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
- Center for Computational Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan
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42
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Han CT, Song J, Chan T, Pruett C, Han S. Electrostatic Environment of Proteorhodopsin Affects the pKa of Its Buried Primary Proton Acceptor. Biophys J 2020; 118:1838-1849. [PMID: 32197061 DOI: 10.1016/j.bpj.2020.02.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Revised: 01/27/2020] [Accepted: 02/27/2020] [Indexed: 01/18/2023] Open
Abstract
The protonation state of embedded charged residues in transmembrane proteins (TMPs) can control the onset of protein function. It is understood that interactions between an embedded charged residue and other charged or polar residues in the moiety would influence its pKa, but how the surrounding environment in which the TMP resides affects the pKa of these residues is unclear. Proteorhodopsin (PR), a light-responsive proton pump from marine bacteria, was used as a model to examine externally accessible factors that tune the pKa of its embedded charged residue, specifically its primary proton acceptor D97. The pKa of D97 was compared between PR reconstituted in liposomes with different net headgroup charges and equilibrated in buffer with different ion concentrations. For PR reconstituted in net positively charged compared to net negatively charged liposomes in low-salt buffer solutions, a drop of the apparent pKa from 7.6 to 5.6 was observed, whereas intrinsic pKa modeled with surface pH calculated from Gouy-Chapman predictions found an opposite trend for the pKa change, suggesting that surface pH does not account for the main changes observed in the apparent pKa. This difference in the pKa of D97 observed from PR reconstituted in oppositely charged liposome environments disappeared when the NaCl concentration was increased to 150 mM. We suggest that protein-intrinsic structural properties must play a role in adjusting the local microenvironment around D97 to affect its pKa, as corroborated with observations of changes in protein side-chain and hydration dynamics around the E-F loop of PR. Understanding the effect of externally controllable factors in tuning the pKa of TMP-embedded charged residues is important for bioengineering and biomedical applications relying on TMP systems, in which the onset of functions can be controlled by the protonation state of embedded residues.
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Affiliation(s)
- Chung-Ta Han
- Department of Chemical Engineering, University of California, Santa Barbara, California
| | - Jichao Song
- Department of Chemical Engineering, University of California, Santa Barbara, California
| | - Tristan Chan
- Department of Chemistry, University of California, Santa Barbara, California
| | - Christine Pruett
- Department of Chemical Engineering, University of California, Santa Barbara, California
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, California; Department of Chemistry, University of California, Santa Barbara, California.
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43
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Li S, Wu L, Zhang X, Jiang X. The Structure of Water Bonded to Phosphate Groups at the Electrified Zwitterionic Phospholipid Membranes/Aqueous Interface. Angew Chem Int Ed Engl 2020; 59:6627-6630. [DOI: 10.1002/anie.202000511] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2020] [Indexed: 12/17/2022]
Affiliation(s)
- Shanshan Li
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Lie Wu
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
| | - Xiaofei Zhang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Xiue Jiang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
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44
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Li S, Wu L, Zhang X, Jiang X. The Structure of Water Bonded to Phosphate Groups at the Electrified Zwitterionic Phospholipid Membranes/Aqueous Interface. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202000511] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Shanshan Li
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Lie Wu
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
| | - Xiaofei Zhang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
| | - Xiue Jiang
- State Key Laboratory of Electroanalytical ChemistryChangchun Institute of Applied ChemistryChinese Academy of Sciences Changchun 130022, Jilin China
- University of Science and Technology of China Hefei Anhui 230029 P. R. China
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45
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Zhang Y, de Aguiar HB, Hynes JT, Laage D. Water Structure, Dynamics, and Sum-Frequency Generation Spectra at Electrified Graphene Interfaces. J Phys Chem Lett 2020; 11:624-631. [PMID: 31899643 DOI: 10.1021/acs.jpclett.9b02924] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The properties of water at an electrified graphene electrode are studied via classical molecular dynamics simulations with a constant potential approach. We show that the value of the applied electrode potential has dramatic effects on the structure and dynamics of interfacial water molecules. While a positive potential slows down the reorientational and translational dynamics of water, an increasing negative potential first accelerates the interfacial water dynamics before a deceleration at very large magnitude potential values. Further, our spectroscopic calculations indicate that the water rearrangements induced by electrified interfaces can be probed experimentally. In particular, the calculated water vibrational sum-frequency generation (SFG) spectra show that SFG specifically reports on the first two water layers at 0 V but that at larger magnitude applied potentials the resulting static field induces long-range contributions to the spectrum. Electrified graphene interfaces provide promising paradigm systems for comprehending both short- and long-range neighboring aqueous system impacts.
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Affiliation(s)
- Yiwei Zhang
- PASTEUR, Department of Chemistry , École normale Supérieure, PSL University, Sorbonne Université, CNRS , 75005 Paris , France
| | - Hilton B de Aguiar
- Département de Physique , École normale supérieure, PSL University, CNRS , 24 rue Lhomond , 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 , United States
| | - Damien Laage
- PASTEUR, Department of Chemistry , École normale Supérieure, PSL University, Sorbonne Université, CNRS , 75005 Paris , France
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46
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Chiang KY, Dalstein L, Wen YC. Affinity of Hydrated Protons at Intrinsic Water/Vapor Interface Revealed by Ion-Induced Water Alignment. J Phys Chem Lett 2020; 11:696-701. [PMID: 31917580 DOI: 10.1021/acs.jpclett.9b03520] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Protons at the water/vapor interface are relevant for atmospheric and environmental processes, yet characterizing their surface affinity on the quantitative level is still challenging. Here we utilize phase-sensitive sum-frequency vibrational spectroscopy to quantify the surface density of protons (or their hydronium form) at the intrinsic water/vapor interface through inspecting the surface-field-induced alignment of water molecules in the electrical double layer of ions. With hydrogen halides in water, the surface adsorption of protons is found to be independent of specific proton-halide anion interactions and to follow a constant adsorption free energy, ΔG ≈ -3.76 (±0.79) kJ/mol, corresponding to a partitioning coefficient of the surface with respect to bulk water by 3.3∼6.2, for bulk ion concentrations up to 0.3 M. Our spectroscopic study not only is of importance in atmospheric chemistry but also offers a microscopic-level basis to develop advanced quantum-mechanical models for molecular simulations.
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Affiliation(s)
- Kuo-Yang Chiang
- Institute of Physics, Academia Sinica , Taipei 11529 , Taiwan , R.O.C
| | - Laetitia Dalstein
- Institute of Physics, Academia Sinica , Taipei 11529 , Taiwan , R.O.C
| | - Yu-Chieh Wen
- Institute of Physics, Academia Sinica , Taipei 11529 , Taiwan , R.O.C
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47
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Gilbile D, Docto D, Kingi D, Kurniawan J, Monahan D, Tang A, Kuhl T. How Well Can You Tailor the Charge of Lipid Vesicles? LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:15960-15969. [PMID: 31608647 PMCID: PMC9044797 DOI: 10.1021/acs.langmuir.9b02163] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Knowledge and control of surface charge or potential is important for tailoring colloidal interactions. In this work, we compare widely used zeta potential (ζ) measurements of charged lipid vesicle surface potential to direct measurements using the surface force apparatus (SFA). Our measurements show good agreement between the two techniques. On varying the fraction of anionic lipids dimyristoylphosphatidylserine (DMPS) or dimyristoylphosphatidylglycerol (DMPG) mixed with zwitterionic dimyristoylphosphatidylcholine (DMPC) from 0 to 100 mol % we observed a near-linear increase in membrane surface charge or potential up to 20-30 mol % charged lipids beyond which charge saturation occurred in physiological (high) salt conditions. Similarly, in low salt concentrations, a linear increase in charge/potential was found but only up to ∼5-10 mol % charged lipids beyond which the surface charge or potential leveled off. While a lower degree of ionization is expected due to the lower dielectric constant (ε ∼ 4) of the lipid acyl chain environment, increasing intramembrane electrostatic repulsion between neighboring charged lipid head groups at higher charge loading contributes to charge suppression. Measured potentials in physiological salt solutions were consistent with predictions using the Gouy-Chapman-Stern-Grahame (GCSG) model of the electrical double layer with Langmuir binding of counterions, but in low salt conditions, the model significantly overestimated the surface charge/potential. The much lower ionization in low salt (maximum ∼1-2% of total lipids ionized) instead was consistent with counterion condensation at the bilayer surface which limited the charge that could be obtained. The strong interplay between membrane composition, lipid headgroup ionization, electrolyte concentration, and solution pH complicates exact prediction and tuning of membrane surface charge for applications. However, the theoretical frameworks used here can provide guidelines to understand this interplay and establish a range of achievable potentials for a system and predict the response to triggers like pH and salt concentration changes.
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48
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Das S, Bonn M, Backus EHG. The Surface Activity of the Hydrated Proton Is Substantially Higher than That of the Hydroxide Ion. Angew Chem Int Ed Engl 2019; 58:15636-15639. [PMID: 31418999 PMCID: PMC6856863 DOI: 10.1002/anie.201908420] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2019] [Indexed: 11/30/2022]
Abstract
The behavior of hydroxide and hydrated protons, the auto-ionization products of water, at surfaces is important for a wide range of applications and disciplines. However, it is unknown at which bulk concentration these ions start to become surface active at the water-air interface. Here, we report changes in the D2 O-air interface in the presence of excess D+ hyd /OD- hyd determined using surface-sensitive vibrational sum-frequency generation (SFG) spectroscopy. The onset of the perturbation of the D2 O surface occurs at a bulk concentration as low as 2.7±0.2 mm D+ hyd . In contrast, a concentration of several hundred mm OD- hyd is required to change the D2 O surface. The hydrated proton is thus orders of magnitude more surface-active than hydroxide at the water-air interface.
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Affiliation(s)
- Sudipta Das
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
| | - Mischa Bonn
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
| | - Ellen H. G. Backus
- Department of Physical ChemistryUniversity of ViennaWähringer Strasse 421090ViennaAustria
- Department of Molecular SpectroscopyMax Planck Institute for Polymer ResearchAckermannweg 1055128MainzGermany
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49
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Dreier LB, Wolde-Kidan A, Bonthuis DJ, Netz RR, Backus EHG, Bonn M. Unraveling the Origin of the Apparent Charge of Zwitterionic Lipid Layers. J Phys Chem Lett 2019; 10:6355-6359. [PMID: 31568720 DOI: 10.1021/acs.jpclett.9b02587] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The structure of water molecules in contact with zwitterionic lipid molecules is of great biological relevance, because biological membranes are largely composed of such lipids. The interaction of the interfacial water molecules with the amphiphilic lipid molecules drives the formation of membranes and greatly influences various processes at the membrane surface, as the field that arises from the aligned interfacial water molecules masks the charges of the lipid headgroups from the approaching metabolites. To increase our understanding of the influence of water molecules on biological processes we study their structure at the interface using sum-frequency generation spectroscopy and molecular dynamics simulations. Interestingly, we find that water molecules at zwitterionic lipid molecules are mainly oriented by the field arising between the two oppositely charged molecular moieties within the lipid headgroups.
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Affiliation(s)
- Lisa B Dreier
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 Mainz , Germany
- Graduate School Materials Science in Mainz , Staudingerweg 9 , 55128 Mainz , Germany
| | - Amanuel Wolde-Kidan
- Fachbereich Physik , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , Germany
| | - Douwe Jan Bonthuis
- Institute of Theoretical and Computational Physics , Graz University of Technology , 8010 Graz , Austria
| | - Roland R Netz
- Fachbereich Physik , Freie Universität Berlin , Arnimallee 14 , 14195 Berlin , 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
| | - Mischa Bonn
- Max Planck Institute for Polymer Research , Ackermannweg 10 , 55128 Mainz , Germany
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50
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Pezzotti S, Galimberti DR, Gaigeot MP. Deconvolution of BIL-SFG and DL-SFG spectroscopic signals reveals order/disorder of water at the elusive aqueous silica interface. Phys Chem Chem Phys 2019; 21:22188-22202. [PMID: 31441490 DOI: 10.1039/c9cp02766a] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Through the prism of the rather controversial and elusive silica/water interface, ab initio DFT-based molecular dynamics simulations of the structure and non-linear SFG spectroscopy of the interface are analysed. Following our recent work [Phys. Chem. Chem. Phys., 2018, 20, 5190-5199], we show that once the interfacial water is decomposed into BIL (Binding Interfacial Layer) and DL (Diffuse Layer) interfacial regions, the SFG signals can be deconvolved and unambiguously interpreted, and a global microscopic understanding on silica/water interfaces can be obtained. By comparing crystalline quartz/water and amorphous (fused) silica/water interfaces, the dependence of interfacial structural and spectroscopic properties on the degree of surface crystallinity is established, while by adding KCl electrolytes at the quartz/water interface, the chaotropic effect of ions on the interfacial molecular arrangement is unveiled. The evolution of structure and SFG spectra of silica/water interfaces with respect to increasing surface deprotonation, i.e., with respect to pH conditions, is also evaluated. Spectroscopic BIL-SFG markers that experimentally allow one detect the water order/disorder in the BIL as a function of surface hydroxylation and ion concentration are revealed, while the pH-induced modulations in the experimentally recorded SFG spectra are rationalized in terms of changes in both BIL and DL SFG signatures.
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Affiliation(s)
- Simone Pezzotti
- LAMBE CNRS UMR8587, Laboratoire Analyse et Modélisation pour la Biologie et l'Environnement, Université d'Evry val d'Essonne, Blvd F. Mitterrand, Bat Maupertuis, 91025 Evry, France.
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