1
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Hui Y, Cui Z, Sim S. Stress-Tolerant, Recyclable, and Renewable Biocatalyst Platform Enabled by Engineered Bacterial Spores. ACS Synth Biol 2022; 11:2857-2868. [PMID: 35878063 DOI: 10.1021/acssynbio.2c00256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Here, we describe a stress-tolerant, recyclable, and renewable biocatalyst platform based on T7 RNA polymerase-enabled high-density protein display on bacterial spores (TIED). TIED uses high-level T7 RNA polymerase-driven expression of recombinant proteins specifically in sporulating cells to allow spontaneous assembly of recombinant fusion proteins on the Bacillus subtilis spore surface. TIED enables high loading density in the range of 106 to 107 recombinant enzymes per spore, robust catalytic activity of displayed enzymes comparable to the respective free enzymes, and enhanced kinetic stability of displayed enzymes in methanol and elevated temperatures. Furthermore, we demonstrate TIED enzymes to be not only recyclable but also fully renewable after the loss of activity through induction of germination and sporulation, enabling perpetual regeneration of these immobilized biocatalysts.
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Affiliation(s)
- Yue Hui
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.,Department of Chemistry, University of California Irvine, Irvine, California 92697, United States
| | - Ziyu Cui
- Department of Chemical and Biomolecular Engineering, University of California Irvine, Irvine, California 92697, United States
| | - Seunghyun Sim
- Department of Chemistry, University of California Irvine, Irvine, California 92697, United States.,Department of Chemical and Biomolecular Engineering, University of California Irvine, Irvine, California 92697, United States.,Department of Biomedical Engineering, University of California Irvine, Irvine, California 92697, United States
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2
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Aruchamy M, Karuppannan S. Effect of Solvent Properties on the Growth, Morphology, and Second Harmonic Generation Ability of 4‐Aminobenzophenone (ABP) Single Crystals. CRYSTAL RESEARCH AND TECHNOLOGY 2021. [DOI: 10.1002/crat.202000246] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Mythili Aruchamy
- Crystal Growth Laboratory Department of Physics School of Physical Sciences Bharathiar University Coimbatore Tamil Nadu 641046 India
| | - Srinivasan Karuppannan
- Crystal Growth Laboratory Department of Physics School of Physical Sciences Bharathiar University Coimbatore Tamil Nadu 641046 India
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3
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Capaldo L, Ravelli D, Fagnoni M. Direct Photocatalyzed Hydrogen Atom Transfer (HAT) for Aliphatic C-H Bonds Elaboration. Chem Rev 2021; 122:1875-1924. [PMID: 34355884 PMCID: PMC8796199 DOI: 10.1021/acs.chemrev.1c00263] [Citation(s) in RCA: 338] [Impact Index Per Article: 112.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
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Direct photocatalyzed
hydrogen atom transfer (d-HAT) can be considered
a method of choice for the elaboration of
aliphatic C–H bonds. In this manifold, a photocatalyst (PCHAT) exploits the energy of a photon to trigger the homolytic
cleavage of such bonds in organic compounds. Selective C–H
bond elaboration may be achieved by a judicious choice of the hydrogen
abstractor (key parameters are the electronic character and the molecular
structure), as well as reaction additives. Different are the classes
of PCsHAT available, including aromatic ketones, xanthene
dyes (Eosin Y), polyoxometalates, uranyl salts, a metal-oxo porphyrin
and a tris(amino)cyclopropenium radical dication. The processes (mainly
C–C bond formation) are in most cases carried out under mild
conditions with the help of visible light. The aim of this review
is to offer a comprehensive survey of the synthetic applications of
photocatalyzed d-HAT.
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Affiliation(s)
- Luca Capaldo
- Flow Chemistry Group, Van't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Davide Ravelli
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
| | - Maurizio Fagnoni
- PhotoGreen Lab, Department of Chemistry, University of Pavia, Viale Taramelli 12, 27100 Pavia, Italy
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4
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Turkin A, Holzapfel M, Agarwal M, Fischermeier D, Mitric R, Schweins R, Gröhn F, Lambert C. Solvent Induced Helix Folding of Defined Indolenine Squaraine Oligomers. Chemistry 2021; 27:8380-8389. [PMID: 33871113 PMCID: PMC8251825 DOI: 10.1002/chem.202101063] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Indexed: 01/01/2023]
Abstract
A protecting group strategy was employed to synthesise a series of indolenine squaraine dye oligomers up to the nonamer. The longer oligomers show a distinct solvent dependence of the absorption spectra, that is, either a strong blue shift or a strong red shift of the lowest energy bands in the near infrared spectral region. This behaviour is explained by exciton coupling theory as being due to H- or J-type coupling of transition moments. The H-type coupling is a consequence of a helix folding in solvents with a small Hansen dispersity index. DOSY NMR, small angle neutron scattering (SANS), quantum chemical and force field calculations agree upon a helix structure with an unusually large pitch and open voids that are filled with solvent molecules, thereby forming a kind of clathrate. The thermodynamic parameters of the folding process were determined by temperature dependent optical absorption spectra.
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Affiliation(s)
- Arthur Turkin
- Institut für Organische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Marco Holzapfel
- Institut für Organische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Mohit Agarwal
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) and Bavarian Polymer Institute (BPI)University of Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
- Institut Max von Laue - Paul Langevin (ILL), DS / LSS71, Avenue des Martyrs - CS 2015638042Grenoble Cedex 9France
| | - David Fischermeier
- Institut für Physikalische und Theoretische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Roland Mitric
- Institut für Physikalische und Theoretische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
- Center for Nanosystems ChemistryUniversität WürzburgAm Hubland97074WürzburgGermany
| | - Ralf Schweins
- Institut Max von Laue - Paul Langevin (ILL), DS / LSS71, Avenue des Martyrs - CS 2015638042Grenoble Cedex 9France
| | - Franziska Gröhn
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) and Bavarian Polymer Institute (BPI)University of Erlangen-NürnbergEgerlandstraße 391058ErlangenGermany
| | - Christoph Lambert
- Institut für Organische ChemieUniversität WürzburgAm Hubland97074WürzburgGermany
- Center for Nanosystems ChemistryUniversität WürzburgAm Hubland97074WürzburgGermany
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5
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Sanders SE, Vanselous H, Petersen PB. Water at surfaces with tunable surface chemistries. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2018; 30:113001. [PMID: 29393860 DOI: 10.1088/1361-648x/aaacb5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Aqueous interfaces are ubiquitous in natural environments, spanning atmospheric, geological, oceanographic, and biological systems, as well as in technical applications, such as fuel cells and membrane filtration. Where liquid water terminates at a surface, an interfacial region is formed, which exhibits distinct properties from the bulk aqueous phase. The unique properties of water are governed by the hydrogen-bonded network. The chemical and physical properties of the surface dictate the boundary conditions of the bulk hydrogen-bonded network and thus the interfacial properties of the water and any molecules in that region. Understanding the properties of interfacial water requires systematically characterizing the structure and dynamics of interfacial water as a function of the surface chemistry. In this review, we focus on the use of experimental surface-specific spectroscopic methods to understand the properties of interfacial water as a function of surface chemistry. Investigations of the air-water interface, as well as efforts in tuning the properties of the air-water interface by adding solutes or surfactants, are briefly discussed. Buried aqueous interfaces can be accessed with careful selection of spectroscopic technique and sample configuration, further expanding the range of chemical environments that can be probed, including solid inorganic materials, polymers, and water immiscible liquids. Solid substrates can be finely tuned by functionalization with self-assembled monolayers, polymers, or biomolecules. These variables provide a platform for systematically tuning the chemical nature of the interface and examining the resulting water structure. Finally, time-resolved methods to probe the dynamics of interfacial water are briefly summarized before discussing the current status and future directions in studying the structure and dynamics of interfacial water.
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Affiliation(s)
- Stephanie E Sanders
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853, United States of America
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6
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Shen S, Lu Y, Li X, Liu X, Chen JG, Hu D. Bioinspired silicification of chloroplast for extended light-harvesting ability. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2017.02.066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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7
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Zobel M. Observing structural reorientations at solvent–nanoparticle interfaces by X-ray diffraction – putting water in the spotlight. ACTA CRYSTALLOGRAPHICA A-FOUNDATION AND ADVANCES 2016; 72:621-631. [DOI: 10.1107/s2053273316013516] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 08/22/2016] [Indexed: 01/29/2023]
Abstract
Nanoparticles are attractive in a wide range of research genres due to their size-dependent properties, which can be in contrast to those of micrometre-sized colloids or bulk materials. This may be attributed, in part, to their large surface-to-volume ratio and quantum confinement effects. There is a growing awareness that stress and strain at the particle surface contribute to their behaviour and this has been included in the structural models of nanoparticles for some time. One significant oversight in this field, however, has been the fact that the particle surface affects its surroundings in an equally important manner. It should be emphasized here that the surface areas involved are huge and, therefore, a significant proportion of solvent molecules are affected. Experimental evidence of this is emerging, where suitable techniques to probe the structural correlations of liquids at nanoparticle surfaces have only recently been developed. The recent validation of solvation shells around nanoparticles has been a significant milestone in advancing this concept. Restructured ordering of solvent molecules at the surfaces of nanoparticles has an influence on the entire panoply of solvent–particle interactions during, for example, particle formation and growth, adhesion forces in industrial filtration, and activities of nanoparticle–enzyme complexes. This article gives an overview of the advances made in solvent–nanoparticle interface research in recent years: from description of the structure of bulk solids and liquidsviamacroscopic planar surfaces, to the detection of nanoscopic restructuring effects. Water–nanoparticle interfaces are given specific attention to illustrate and highlight their similarity to biological systems.
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9
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Zobel M, Neder RB, Kimber SAJ. Universal solvent restructuring induced by colloidal nanoparticles. Science 2015; 347:292-4. [DOI: 10.1126/science.1261412] [Citation(s) in RCA: 147] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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10
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Dragneva N, Floriano WB, Stauffer D, Mawhinney RC, Fanchini G, Rubel O. Favorable adsorption of capped amino acids on graphene substrate driven by desolvation effect. J Chem Phys 2013; 139:174711. [DOI: 10.1063/1.4828437] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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11
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Woods BL, Walker RA. pH Effects on Molecular Adsorption and Solvation of p-Nitrophenol at Silica/Aqueous Interfaces. J Phys Chem A 2013; 117:6224-33. [DOI: 10.1021/jp400482v] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- B. Lauren Woods
- Department
of Chemistry and Biochemistry, Montana State University, Bozeman, Montana
59717, United States
| | - Robert A. Walker
- Department
of Chemistry and Biochemistry, Montana State University, Bozeman, Montana
59717, United States
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12
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Gobrogge EA, Woods BL, Walker RA. Liquid organization and solvation properties at polar solid/liquid interfaces. Faraday Discuss 2013; 167:309-27. [DOI: 10.1039/c3fd00071k] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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13
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Nelson KV, Benjamin I. Electronic Absorption Line Shapes at the Water Liquid/Vapor Interface. J Phys Chem B 2012; 116:4286-91. [DOI: 10.1021/jp3010037] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Katherine V. Nelson
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064,
United States
| | - Ilan Benjamin
- Department of Chemistry and Biochemistry, University of California, Santa Cruz, California 95064,
United States
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14
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Affiliation(s)
- Francisco Zaera
- Department of Chemistry, University of California, Riverside, California 92521, United States
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15
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Mello R, Martínez-Ferrer J, Alcalde-Aragonés A, Varea T, Acerete R, González-Núñez ME, Asensio G. Reactions at Interfaces: Oxygenation of n-Butyl Ligands Anchored on Silica Surfaces with Methyl(trifluoromethyl)dioxirane. J Org Chem 2011; 76:10129-39. [DOI: 10.1021/jo2019703] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Rossella Mello
- Departamento de Química Orgánica,
Facultad
de Farmacia, Universidad de Valencia, Avda.
Vicente Andrés Estellés s.n., 46100-Burjassot, Valencia,
Spain
| | - Jaime Martínez-Ferrer
- Departamento de Química Orgánica,
Facultad
de Farmacia, Universidad de Valencia, Avda.
Vicente Andrés Estellés s.n., 46100-Burjassot, Valencia,
Spain
| | - Ana Alcalde-Aragonés
- Departamento de Química Orgánica,
Facultad
de Farmacia, Universidad de Valencia, Avda.
Vicente Andrés Estellés s.n., 46100-Burjassot, Valencia,
Spain
| | - Teresa Varea
- Departamento de Química Orgánica,
Facultad
de Farmacia, Universidad de Valencia, Avda.
Vicente Andrés Estellés s.n., 46100-Burjassot, Valencia,
Spain
| | - Rafael Acerete
- Departamento de Química Orgánica,
Facultad
de Farmacia, Universidad de Valencia, Avda.
Vicente Andrés Estellés s.n., 46100-Burjassot, Valencia,
Spain
| | - María Elena González-Núñez
- Departamento de Química Orgánica,
Facultad
de Farmacia, Universidad de Valencia, Avda.
Vicente Andrés Estellés s.n., 46100-Burjassot, Valencia,
Spain
| | - Gregorio Asensio
- Departamento de Química Orgánica,
Facultad
de Farmacia, Universidad de Valencia, Avda.
Vicente Andrés Estellés s.n., 46100-Burjassot, Valencia,
Spain
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17
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Buchbinder AM, Weitz E, Geiger FM. When the Solute Becomes the Solvent: Orientation, Ordering, and Structure of Binary Mixtures of 1-Hexanol and Cyclohexane over the (0001) α-Al2O3 Surface. J Am Chem Soc 2010; 132:14661-8. [DOI: 10.1021/ja1068504] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Avram M. Buchbinder
- Department of Chemistry and the Institute for Catalysis in Energy Processes, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
| | - Eric Weitz
- Department of Chemistry and the Institute for Catalysis in Energy Processes, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
| | - Franz M. Geiger
- Department of Chemistry and the Institute for Catalysis in Energy Processes, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208
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18
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Brindza MR, Ding F, Fourkas JT, Walker RA. n-alkane adsorption to polar silica surfaces. J Chem Phys 2010; 132:114701. [DOI: 10.1063/1.3336727] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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19
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Hydrogen-bonding molecular ruler surfactants as probes of specific solvation at liquid/liquid interfaces. Anal Bioanal Chem 2009; 395:1063-73. [DOI: 10.1007/s00216-009-2957-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 06/27/2009] [Accepted: 07/06/2009] [Indexed: 11/27/2022]
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20
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Brindza MR, Walker RA. Differentiating Solvation Mechanisms at Polar Solid/Liquid Interfaces. J Am Chem Soc 2009; 131:6207-14. [DOI: 10.1021/ja810117f] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Michael R. Brindza
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742
| | - Robert A. Walker
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742
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21
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Ueno K, Imaizumi S, Hata K, Watanabe M. Colloidal interaction in ionic liquids: effects of ionic structures and surface chemistry on rheology of silica colloidal dispersions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2009; 25:825-831. [PMID: 19072578 DOI: 10.1021/la803124m] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
To understand the important factors that dominate colloidal stability in ionic liquids (ILs), rheology of the dispersions of hydrophilic and hydrophobic silica nanoparticles were investigated in ILs with different ionic structures. The dispersion of hydrophilic silica nanoparticles in [BF(4)] anion-based ILs and in an IL containing a hydroxyl group, 1-(2-hydroxyethyl)-3-methylimidazolium bis(trifluoromethane sulfonyl)amide ([C(2)OHmim][NTf(2)]), showed an intriguing shear thickening response. Nonflocculation of the hydrophilic silica nanoparticles in the [BF(4)] anion-based ILs and in [C(2)OHmim][NTf(2)], where the interparticle electrostatic repulsion appears to be depressed, suggests that an IL-based steric hindrance or solvation force provides an effective repulsive barrier for the colloidal aggregation. On the other hand, the other dispersions presented shear thinning behavior with an increase in shear rates and gelled at relatively low particle concentrations. The elastic modulus (G') of the gels formed by the hydrophilic silica was correlated with the polarity scale, lambda(Cu), of the ILs, indicating that the silica-IL interactions, especially the silica-anion interactions, appear to affect the rheological behavior, even in flocculated systems. All the ILs used in this study can be solidified by the addition of hydrophobic silica particles. The rheological behavior of the silica colloidal dispersions was strongly affected by the ionic structure of the ILs and the surface structure of the silica particles.
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Affiliation(s)
- Kazuhide Ueno
- Department of Chemistry and Biotechnology, Yokohama National University 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan
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22
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Banerjee D, Pal SK. Excited-State Solvation and Proton Transfer Dynamics of DAPI in Biomimetics and Genomic DNA. J Phys Chem A 2008; 112:7314-20. [DOI: 10.1021/jp801778e] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Debapriya Banerjee
- Unit for Nano Science & Technology, Department of Chemical, Biological & Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India
| | - Samir Kumar Pal
- Unit for Nano Science & Technology, Department of Chemical, Biological & Macromolecular Sciences, S. N. Bose National Centre for Basic Sciences, Block JD, Sector III, Salt Lake, Kolkata 700 098, India
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23
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Heger D, Klán P. Interactions of organic molecules at grain boundaries in ice: A solvatochromic analysis. J Photochem Photobiol A Chem 2007. [DOI: 10.1016/j.jphotochem.2006.10.012] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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24
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Smith WE, Zukoski CF. Role of solvation forces in the gelation of fumed silica–alcohol suspensions. J Colloid Interface Sci 2006; 304:348-58. [PMID: 16979179 DOI: 10.1016/j.jcis.2006.08.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2006] [Revised: 08/11/2006] [Accepted: 08/12/2006] [Indexed: 11/18/2022]
Abstract
Aggregation and gelation kinetics of fumed silica were investigated by altering the solvent-surface interactions. Native and surface-modified (hydrophobic) fumed silica particles were dispersed in short-chain linear alcohols. Based on the kinetics of aggregation and gelation, we show that the solvent-surface interactions have a tremendous impact on the bulk suspension properties. The gelation kinetics were qualitatively similar in all of the fumed silica-alcohol samples, and the gel times for all the alcohols were captured on a master curve requiring two parameters. The two parameters, the stability ratio and critical volume fraction, describe the two regimes of gelation. At low concentrations, gelation occurs due to aggregation of the particles diffusing over a potential barrier (15-25 kT). The rate of aggregation and time to gelation then scales with the stability ratio. At high particle loadings, gelation occurs at a critical volume fraction due to localization in a secondary minimum with a depth of 3-4 kT. These observations are supported by evidence of hydrogen bonding between the solvent and the particle, creating oscillatory solvation forces that govern the magnitude of these two parameters.
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Affiliation(s)
- William E Smith
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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25
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Yamaguchi S, Tahara T. Determining electronic spectra at interfaces by electronic sum frequency generation: One- and two-photon double resonant oxazine 750 at the air/water interface. J Chem Phys 2006; 125:194711. [PMID: 17129154 DOI: 10.1063/1.2375093] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The second-order nonlinear electronic spectra were measured for a dye oxazine 750 (OX750) adsorbed at the air/water interface using the multiplex electronic sum frequency generation (ESFG) spectroscopy recently developed by our group. The excitation-wavelength dependence of the ESFG spectrum was investigated, and a global fitting analysis was performed to separate contributions of one- and two-photon resonances. The analysis yielded linear interface electronic spectra in the one- and two-photon resonance regions, which can be directly compared to bulk absorption spectra. A two-dimensional plot of the linear interface electronic spectra is newly proposed to graphically represent all the essential information on the electronic structure of interfacial molecules. On this new analytical basis of the ESFG spectroscopy, the spectroscopic properties of OX750 at the interface are discussed.
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Affiliation(s)
- Shoichi Yamaguchi
- Molecular Spectroscopy Laboratory, RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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26
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dos Santos DJVA, Gomes JANF. Structure and Properties of Hexadecyltrimethylammonium Chloride Monolayers in Contact with Oil Films with Different Thicknesses. J Phys Chem B 2004. [DOI: 10.1021/jp0493778] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel J. V. A. dos Santos
- REQUIMTE/Departamento de Quimica da Faculdade de Ciencias da Universidade do Porto, R. Campo Alegre 687, 4169-007 Porto, Portugal
| | - Jose A. N. F. Gomes
- REQUIMTE/Departamento de Quimica da Faculdade de Ciencias da Universidade do Porto, R. Campo Alegre 687, 4169-007 Porto, Portugal
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27
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Steel WH, Lau YY, Beildeck CL, Walker RA. Solvent Polarity across Weakly Associating Interfaces. J Phys Chem B 2004. [DOI: 10.1021/jp0498318] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- William H. Steel
- Department of Chemistry and Biochemistry, University of Maryland, College Park, College Park, Maryland 20742
| | - Yuen Y. Lau
- Department of Chemistry and Biochemistry, University of Maryland, College Park, College Park, Maryland 20742
| | - Carmen L. Beildeck
- Department of Chemistry and Biochemistry, University of Maryland, College Park, College Park, Maryland 20742
| | - Robert A. Walker
- Department of Chemistry and Biochemistry, University of Maryland, College Park, College Park, Maryland 20742
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