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Sasaki K, Takatsuka M, Shinyashiki N, Ngai KL. Relating the dynamics of hydrated poly(vinyl pyrrolidone) to the dynamics of highly asymmetric mixtures and polymer blends. J Mol Liq 2021. [DOI: 10.1016/j.molliq.2021.115907] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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2
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Shinyashiki N, Miyara M, Nakano S, Yamamoto W, Ueshima M, Imoto D, Sasaki K, Kita R, Yagihara S. Dielectric relaxation strength and magnitude of dipole moment of poly(vinyl pyrrolidone)in polar solutions. J Mol Liq 2013. [DOI: 10.1016/j.molliq.2013.02.020] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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3
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Liu C, Zhao K. Effects of concentration and temperature on the dynamic behavior of PAA-g-PEO aqueous solutions with different counterion species: a dielectric spectroscopy study. J Phys Chem B 2012; 116:763-74. [PMID: 22145987 DOI: 10.1021/jp2102379] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Dielectric properties of PAA-g-PEO-7% solutions with different counterions were measured as a function of concentration and temperature over a frequency range of 40 Hz to 110 MHz. After the contribution of electrode polarization effects was subtracted, the dielectric spectra of PAA-g-PEO-7% solutions showed three relaxation processes in the experimental frequency range, named low-, mid-, and high-frequency relaxation. The observed three relaxations were strictly analyzed by using the Cole-Cole relaxation function, and the dielectric parameters (dielectric increment Δε and the relaxation time τ) were obtained. The scaling relation of dielectric increment and relaxation time of high frequency with concentration C(p) were obtained and compared with the predictions of scaling theories. The information on the dynamics and microstructure of PAA-g-PEO-7% was obtained. Using different counterion species, the mid- and high-frequency relaxation mechanisms were attributed to the fluctuation of condensed counterions and free counterions, respectively, and the low-frequency relaxation was considered to be caused by the interface polarization of a complex formed by the hydrogen bonding between carboxylic group of PAA and ether oxygen on the side-chain PEO. In addition, by means of Eyring equation, the thermodynamic parameters, enthalpy change ΔH and entropy change ΔS, of the three relaxations were calculated from the relaxation time and discussed from the microscopic thermodynamical view.
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Affiliation(s)
- Chunyan Liu
- College of Chemistry, Beijing Normal University, Beijing, China
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4
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Shinyashiki N, Spanoudaki A, Yamamoto W, Nambu E, Yoneda K, Kyritsis A, Pissis P, Kita R, Yagihara S. Segmental Relaxation of Hydrophilic Poly(vinylpyrrolidone) in Chloroform Studied by Broadband Dielectric Spectroscopy. Macromolecules 2011. [DOI: 10.1021/ma102394s] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Naoki Shinyashiki
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
| | - Anna Spanoudaki
- Department of Applied Mathematics and Physics, National Technical University of Athens, Heroon Polytechneiou 9, 15780 Athens, Greece
| | - Wataru Yamamoto
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
| | - Eri Nambu
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
| | - Kaoru Yoneda
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
| | - Apostolos Kyritsis
- Department of Applied Mathematics and Physics, National Technical University of Athens, Heroon Polytechneiou 9, 15780 Athens, Greece
| | - Polycarpos Pissis
- Department of Applied Mathematics and Physics, National Technical University of Athens, Heroon Polytechneiou 9, 15780 Athens, Greece
| | - Rio Kita
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
| | - Shin Yagihara
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
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5
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Stukalin EB, Douglas JF, Freed KF. Plasticization and antiplasticization of polymer melts diluted by low molar mass species. J Chem Phys 2010; 132:084504. [PMID: 20192304 DOI: 10.1063/1.3304738] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
An analysis of glass formation for polymer melts that are diluted by structured molecular additives is derived by using the generalized entropy theory, which involves a combination of the Adam-Gibbs model and the direct computation of the configurational entropy based on a lattice model of polymer melts that includes monomer structural effects. Our computations indicate that the plasticization and antiplasticization of polymer melts depend on the molecular properties of the additive. Antiplasticization is accompanied by a "toughening" of the glass mixture relative to the pure polymer, and this effect is found to occur when the diluents are small species with strongly attractive interactions with the polymer matrix. Plasticization leads to a decreased glass transition temperature T(g) and a "softening" of the fragile host polymer in the glass state. Plasticization is prompted by small additives with weakly attractive interactions with the polymer matrix. However, the latter situation can lead to phase separation if the attractive interactions are sufficiently strong. The shifts in T(g) of polystyrene diluted by fully flexible short oligomers (up to 20% mass of diluent) are evaluated from the computations, along with the relative changes in the isothermal compressibility at T(g) (a softening or toughening effect) to characterize the extent to which the additives act as antiplasticizers or plasticizers. The theory predicts that a decreased fragility can accompany both antiplasticization and plasticization of the glass by molecular additives. The general reduction in the T(g) of polymers by molecular additives is rationalized by analyzing the influence of the diluent's properties (cohesive energy, chain length, and stiffness) on glass formation in fluid mixtures and the variation of fragility is discussed in relation to changes in the molecular packing in diluted polymer melts. Our description of constant temperature glass formation upon increasing the diluent concentration directly leads to the Angell equation (tau(alpha) approximately A exp{B/(phi(0,p)-phi(p))}) for the structural relaxation time as function of the polymer concentration, where the extrapolated "zero mobility concentration" phi(0,p) calculated from the theory scales linearly with the inverse polymerization index N.
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Affiliation(s)
- Evgeny B Stukalin
- Department of Chemistry and The James Franck Institute, University of Chicago, Chicago, IL 60637, USA.
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6
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Kundu SK, Yagihara S, Yoshida M, Shibayama M. Microwave Dielectric Study of an Oligomeric Electrolyte Gelator by Time Domain Reflectometry. J Phys Chem B 2009; 113:10112-6. [PMID: 19572678 DOI: 10.1021/jp901043h] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shyamal Kumar Kundu
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan, Department of Physics, School of Science, Tokai University, 1117 Kitakanane, Hiratsuka, Kanagawa 259-1292, Japan, and Nanotechnology Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Shin Yagihara
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan, Department of Physics, School of Science, Tokai University, 1117 Kitakanane, Hiratsuka, Kanagawa 259-1292, Japan, and Nanotechnology Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Masaru Yoshida
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan, Department of Physics, School of Science, Tokai University, 1117 Kitakanane, Hiratsuka, Kanagawa 259-1292, Japan, and Nanotechnology Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
| | - Mitsuhiro Shibayama
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8581, Japan, Department of Physics, School of Science, Tokai University, 1117 Kitakanane, Hiratsuka, Kanagawa 259-1292, Japan, and Nanotechnology Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan
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7
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Stukalin EB, Douglas JF, Freed KF. Multistep relaxation in equilibrium polymer solutions: a minimal model of relaxation in "complex" fluids. J Chem Phys 2009; 129:094901. [PMID: 19044888 DOI: 10.1063/1.2976341] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We examine the rheological and dielectric properties of solutions of equilibrium self-assembling particles and molecules that form polydisperse chains whose average length depends on temperature and concentration (free association model). Relaxation of the self-assembling clusters proceeds by motions associated either with cluster rotations, with diffusive internal chain dynamics, or with interchain entanglement interactions. A hierarchy of models is used to emphasize different physical effects: Unentangled rodlike clusters, unentangled flexible polymers, and entangled chains. All models yield a multistep relaxation for low polymer scission rates ("persistent polymers"). The short time relaxation is nearly exponential and is dominated by the monomeric species and solvent, and the long time relaxation is approximately a stretched exponential, exp[-(t/tau)(beta)], a behavior that arises from an averaging over the equilibrium chain length distribution and the internal relaxation modes of the assembled structures. Relaxation functions indicate a bifurcation of the relaxation function into fast and slow contributions upon passing through the polymerization transition. The apparent activation energy for the long time relaxation becomes temperature dependent, while the fast monomeric relaxation process remains Arrhenius. The effective exponent beta(T), describing the long time relaxation process, varies monotonically from near unity above the polymerization temperature to a low temperature limit, beta approximately 13, when the self-assembly process is complete. The variation in the relaxation function with temperature is represented as a function of molecular parameters, such as the average chain length, friction coefficient, solvent viscosity, and the reaction rates for particle association and dissociation.
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Affiliation(s)
- Evgeny B Stukalin
- The James Franck Institute, University of Chicago, Chicago, Illinois 60637, USA.
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Sengwa RJ, Sankhla S. Dielectric Dispersion Study of Poly(vinyl Pyrrolidone)–Polar Solvent Solutions in the Frequency Range 20 Hz–1 MHz. J MACROMOL SCI B 2007. [DOI: 10.1080/00222340701388938] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- R. J. Sengwa
- a Dielectric Research Laboratory, Department of Physics , J N V University , Jodhpur, Rajasthan, India
| | - Sonu Sankhla
- a Dielectric Research Laboratory, Department of Physics , J N V University , Jodhpur, Rajasthan, India
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9
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Dielectric dispersion study of coexisting phases of aqueous polymeric solution: Poly(vinyl alcohol)+poly(vinyl pyrrolidone) two-phase systems. POLYMER 2007. [DOI: 10.1016/j.polymer.2007.03.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Shinyashiki N, Imoto D, Yagihara S. Broadband Dielectric Study of Dynamics of Polymer and Solvent in Poly(vinyl pyrrolidone)/Normal Alcohol Mixtures. J Phys Chem B 2007; 111:2181-7. [PMID: 17288470 DOI: 10.1021/jp065414e] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Broadband dielectric measurements of poly(vinyl pyrrolidone) (PVP)-monohydroxyl alcohol mixtures of various normal alcohols with the number of carbon atoms per molecule ranging from 1 to 9 were made in the frequency range of 20 Hz to 20 GHz at 25 degrees C. Two relaxation processes due to the reorientation of dipoles on the PVP and alcohol molecules were observed. The relaxation process at frequencies higher than 100 MHz is the primary process of alcohols, and that at frequencies lower than 10 MHz is attributed to the local chain motion of PVP. For mixtures of alcohol molecules that are smaller than propanol, the relaxation time of the alcohol increases with increasing PVP concentration, whereas for mixtures of alcohol molecules larger than butanol, the relaxation time of the alcohol decreases with increasing PVP concentration. The increase in the density of hydrogen-bonding sites upon the addition of PVP reduces the relaxation time of alcohol in the mixture, and vice versa. The relaxation time of the local chain motion of PVP increases with PVP concentration and solvent viscosity. Different time scales of the molecular motions of polymer and solvent coexist in homogeneous mixtures with hydrogen-bonded polar solvent and polymer.
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Affiliation(s)
- N Shinyashiki
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
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11
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Shinyashiki N, Sengwa RJ, Tsubotani S, Nakamura H, Sudo S, Yagihara S. Broadband Dielectric Study of Dynamics of Poly(vinyl pyrrolidone)−Ethylene Glycol Oligomer Blends. J Phys Chem A 2006; 110:4953-7. [PMID: 16610812 DOI: 10.1021/jp0605193] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Broadband dielectric measurements for blends of poly(vinyl pyrrolidone) (PVP) and ethylene glycol oligomer (EGO) from 0 to 40 wt % PVP were carried out at 25 degrees C in the frequency range from 20 Hz to 20 GHz. The EGOs used in this study were ethylene glycol (EG), diethylene glycol (2EG), and PEG400 (MW = 400). For the PVP-EG, -2EG, and -PEG400 blends, relaxation processes caused by the motion of EGO in the GHz range and the micro-Brownian motion of the PVP chain at 10 kHz-1 MHz were observed. Although the PVP-EGO blend is miscible, relaxation processes caused by the molecular motion of EGO and the local chain motion of PVP were observed individually. The relaxation time of the local chain motion of PVP showed a strong PVP concentration dependence and a solvent viscosity dependence, which are similar to those reported so far for the solutions in nonpolar solvents.
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Affiliation(s)
- N Shinyashiki
- Department of Physics, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
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12
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Sengwa RJ, Abhilasha, More NM, Mehrotra SC. Dynamic structure of poly(vinyl pyrrolidone)/ethyl alcohol mixtures studied by time domain reflectometry. ACTA ACUST UNITED AC 2005. [DOI: 10.1002/polb.20401] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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13
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Sun Y, Ishida T, Hayakawa S. Dielectric study of heat-denatured ovalbumin in aqueous solution by time domain reflectometry method. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2004; 52:2351-2357. [PMID: 15080645 DOI: 10.1021/jf030538z] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The dielectric behavior of native and heat-denatured ovalbumins (OVAs) from three avian species in aqueous solution was examined over a frequency range of 100 kHz to 20 GHz, using the time domain reflectometry (TDR) method. For the native OVA solutions, three kinds of relaxation processes were observed at around 10 MHz, 100 MHz, and 20 GHz, respectively; these could be assigned to the overall rotation of protein molecules, the reorientations of the bound water, and the free water molecules, respectively. For the heat-denatured samples, three relaxation processes were also observed. However, the relaxation process at approximately 100 MHz originated via a different mechanism other than the reorientation of bound water, namely, the micro-Brownian motion of peptide chains of heat-denatured protein. From the observed relaxation process at approximately 100 MHz, the relaxation strength of heat-denatured OVA solution for duck was higher than that of OVA solutions for hen and guinea fowl and showed the pH dependency from pH 7.0 to 8.0 for OVAs obtained from all three species. Furthermore, the results demonstrated that the relaxation strength was closely related to surface hydrophobicity of protein molecules and gel rheological properties. It was suggested that the difference in the surface hydrophobicity of protein influenced the dielectric behavior of water around denatured protein, whereas the dielectric behavior of denatured protein could be an indication of the gel rheological properties. Such studies can aid in the understanding of the different network structures of OVA gels from three avian species.
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Affiliation(s)
- Yuanxia Sun
- Department of Biochemistry and Food Science, Kagawa University, Ikenobe, Miki, Kagawa 761-0795, Japan.
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14
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Miura N, Yagihara S, Mashimo S. Microwave Dielectric Properties of Solid and Liquid Foods Investigated by Time-domain Reflectometry. J Food Sci 2003. [DOI: 10.1111/j.1365-2621.2003.tb09656.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Sengwa R, Abhilasha, More N. Dielectric relaxation and molecular dynamics in poly(vinyl pyrrolidone)–ethyl alcohol mixtures in pure liquid state and in non-polar solvent. POLYMER 2003. [DOI: 10.1016/s0032-3861(03)00007-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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16
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Sen S, Sukul D, Dutta P, Bhattacharyya K. Solvation Dynamics in Aqueous Polymer Solution and in Polymer−Surfactant Aggregate. J Phys Chem B 2002. [DOI: 10.1021/jp0118672] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Sobhan Sen
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Dipankar Sukul
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Partha Dutta
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
| | - Kankan Bhattacharyya
- Physical Chemistry Department, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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17
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Hayashi Y, Shinyashiki N, Yagihara S, Yoshiba K, Teramoto A, Nakamura N, Miyazaki Y, Sorai M, Wang Q. Ordering in aqueous polysaccharide solutions. I. Dielectric relaxation in aqueous solutions of a triple-helical polysaccharide schizophyllan. Biopolymers 2002; 63:21-31. [PMID: 11754345 DOI: 10.1002/bip.1059] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Deuterium oxide solutions of a triple-helical polysaccharide schizophyllan, undergoing an order-disorder transition centered around 17 degrees C, were studied by the time-domain reflectometry (TDR) to obtain dielectric dispersions in the solution and frozen states. In the solution state, the dispersion below the transition temperature is resolved in three dispersions (relaxation times at 0 degrees C) ascribed to side chain glucose residue (1; 102 ns), structured water (s; 2.0 ns) and bulk water (h), respectively, from low to high frequencies. Bulk water is divided into slow water (h2; 0.04 ns) and free or pure water (h1; 0.02 ns). Above the transition temperature structured water almost disappears and is compensated by slow water. Structured water is similar to bound water for proteins but different from it because of this transition behavior. Another dispersion (l) seen at the lowest frequency is assigned to the rotation of side-chain glucose residue coupled with hydrated water. Parts of this dispersion and structured water are suggested to constitute bound water. In the frozen state were observed a major dispersion (h; 0.14 ns) and a minor one (m; 28 ns), which were ascribed to considerably mobile and less mobile waters. They are similar to but not exactly the same as that for unfreezable water in bovine serum albumin solutions argued by Miura et al. (Biopolymers, 1995, Vol. 36, p. 9). Water is molded into different structures by the triple helix.
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Affiliation(s)
- Yoshihito Hayashi
- Department of Physics, Faculty of Science, Tokai University, Hiratsuka-shi, Kanagawa 259-12, Japan
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18
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Ryabov YE, Feldman Y, Shinyashiki N, Yagihara S. The symmetric broadening of the water relaxation peak in polymer–water mixtures and its relationship to the hydrophilic and hydrophobic properties of polymers. J Chem Phys 2002. [DOI: 10.1063/1.1471551] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Barker SA, He R, Craig DQ. Low frequency dielectric investigations into the relaxation behavior of frozen polyvinylpyrrolidone-water systems. J Pharm Sci 2001; 90:157-64. [PMID: 11169532 DOI: 10.1002/1520-6017(200102)90:2<157::aid-jps6>3.0.co;2-c] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The low frequency dielectric response of aqueous solutions containing 0, 1, 5, and 10% w/v polyvinylpyrrolidone (PVP) was studied to characterize the low temperature relaxation behavior of these systems. Complementary modulated temperature differential scanning calorimetry (MTDSC) studies allowed measurement of the glass transition temperature for these materials, corresponding to the behavior of the nonfrozen phase. Dielectric investigations in the frequency range of 10(6) to 10(-2) Hz were performed on the systems in the liquid state, with a Maxwell-Wagner response noted for both the PVP solutions and water. The solid-phase responses were studied over a range of temperatures down to -70 degrees C, with a relaxation peak observed for the PVP systems in the kilohertz region. The spectra were modeled using the Havriliak-Negami equation and the corresponding relaxation times were calculated, with a satisfactory fit to the Arrhenius equation noted. The calculated activation energies were similar to literature values for the dielectric relaxation of water. It is suggested that the dielectric response is primarily a reflection of the relaxation behavior of the water molecules in the nonfrozen fraction, thereby indicating that the dielectric technique may yield insights into specific components of frozen aqueous systems.
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Affiliation(s)
- S A Barker
- The School of Pharmacy, The Queen's University of Belfast, 97 Lisburn Road, Belfast BT9 7BL, Northern Ireland, United Kingdom
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20
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Hayashi Y, Miura N, Shinyashiki N, Yagihara S, Mashimo S. Globule-coil transition of denatured globular protein investigated by a microwave dielectric technique. Biopolymers 2000; 54:388-97. [PMID: 10951325 DOI: 10.1002/1097-0282(200011)54:6<388::aid-bip30>3.0.co;2-k] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A mechanism for the gel-glass transition of denatured globular protein has been explained from the viewpoint of the globule-coil transition with microwave dielectric measurements using a time domain reflectometry (TDR) method. Boiled egg white, which is an aqueous gel of egg white prepared by heat treatment at 100 degrees C, becomes a glass on drying. In the gel state, the relaxation processes corresponding to the orientation of bulk water and the micro-Brownian motion of peptide chains of denatured protein were observed around 10 GHz and 10 MHz, respectively. When the gel-glass transition occurred, the relaxation strength for bulk water decreased rapidly as evaporation and breaking of water structure occurred. Simultaneously, the relaxation strength for micro-Brownian motion increased abruptly, as the structure of globular protein varied from globule state to coiled state. It is considered that the protein molecule spreads out and takes up a coiled state by reductions of hydrophobic and hydrophilic interactions of the globular protein. These reductions occur through a decrease in the amount of water.
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Affiliation(s)
- Y Hayashi
- Department of Physics, Tokai University, Hiratsuka-shi, Kanagawa, 259-1292, Japan
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21
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Murthy. Experimental Study of the Dynamics of Water and the Phase behavior of the Supercooled Aqueous Solutions of Propylene Glycol, Glycerol, Poly(ethylene glycol)s, and Poly(vinylpyrrolidone). J Phys Chem B 2000. [DOI: 10.1021/jp9931915] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Murthy
- School of Physical Sciences, Jawaharlal Nehru University, New Delhi, 110 067, India
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22
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Nandi N, Bhattacharyya K, Bagchi B. Dielectric relaxation and solvation dynamics of water in complex chemical and biological systems. Chem Rev 2000; 100:2013-46. [PMID: 11749282 DOI: 10.1021/cr980127v] [Citation(s) in RCA: 688] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- N Nandi
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore, 560012, India
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23
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Shinyashiki N, Yagihara S. Comparison of Dielectric Relaxations of Water Mixtures of Poly(vinylpyrrolidone) and 1-Vinyl-2-pyrrolidinone. J Phys Chem B 1999. [DOI: 10.1021/jp983800t] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Naoki Shinyashiki
- Department of Physics, School of Science, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
| | - Shin Yagihara
- Department of Physics, School of Science, Tokai University, Hiratsuka, Kanagawa 259-1292, Japan
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24
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Shinyashiki N, Yagihara S, Arita I, Mashimo S. Dynamics of Water in a Polymer Matrix Studied by a Microwave Dielectric Measurement. J Phys Chem B 1998. [DOI: 10.1021/jp9729627] [Citation(s) in RCA: 113] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Naoki Shinyashiki
- Department of Physics, Tokai University, Hiratsuka-shi, Kanagawa 259-12, Japan
| | - Shin Yagihara
- Department of Physics, Tokai University, Hiratsuka-shi, Kanagawa 259-12, Japan
| | - Izumi Arita
- Department of Physics, Tokai University, Hiratsuka-shi, Kanagawa 259-12, Japan
| | - Satoru Mashimo
- Department of Physics, Tokai University, Hiratsuka-shi, Kanagawa 259-12, Japan
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25
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Naito S, Hoshi M, Mashimo S. In vivo dielectric analysis of free water content of biomaterials by time domain reflectometry. Anal Biochem 1997; 251:163-72. [PMID: 9299012 DOI: 10.1006/abio.1997.2256] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A method of in vivo analysis of the free water content in living organisms by dielectric analysis in the time domain is described. Human skin is chosen as an example of living tissue. The cells suitable for the measurement of various layers of human skin and calculation procedures for the waveform reflected from the probe end are described. The approach was confirmed to be effective for the determination of the water content through measurement of the standard samples, keratin-water mixtures. This method was also applied to human skin in vivo. Water content data measured with a probe specially designed for surface layer analysis were sensitive to humidity around the subject. The formula expressing the relation between the electrical field character of the probe, the permittivity depth profile, and the measured permittivity was used to analyze the water content profile as a function of the depth from the skin surface. The use of several kinds of probes, differing in their electric field characteristics, permitted evaluation of the water content depth profile of human skin. This procedure is easy and applicable to any sample due to its simplicity. The measurement needs only a touch of the probe on a sample spot. It is therefore a promising method of physicochemical research on living organisms and biomaterials.
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Affiliation(s)
- S Naito
- Biological Science Laboratories, Kao Corporation, 2606 Akabane, Ichikai, Haga, Tochigi, 321-34, Japan
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Shinyashiki N, Matsumura Y, Mashimo S, Yagihara S. Dielectric study on coupling constant of lower critical solution of poly (vinylmethylether) in water. J Chem Phys 1996. [DOI: 10.1063/1.471354] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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27
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Yoshioka S, Aso Y, Otsuka T, Kojima S. Water mobility in poly(ethylene glycol)-, poly(vinylpyrrolidone)-, and gelatin-water systems, as indicated by dielectric relaxation time, spin-lattice relaxation time, and water activity. J Pharm Sci 1995; 84:1072-7. [PMID: 8537884 DOI: 10.1002/jps.2600840908] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The mobility of water molecules present in poly(ethylene glycol) (PEG)-, poly(vinylpyrrolidone) (PVP)-, and gelatin-water systems was determined by dielectric relaxation and 17O NMR spectroscopy. Water activity was also measured. Dielectric relaxation spectra indicate that all the polymer systems studied contained water exhibiting a dispersion at a frequency > 10(9) Hz; in other words, water with high mobility close to that of bulk water. The dielectric relaxation time of the highly mobile water increased as polymer concentration increased. The PVP- and gelatin-water systems also contained water exhibiting a dispersion at a frequency < 10(9) Hz, which can be considered to be "bound water" with a restricted mobility because of its association with polymer molecules. Dielectric relaxation spectroscopy was used to determine water mobility separately for the populations of highly mobile water and bound water, whereas NMR relaxation spectroscopy was used to determine the average mobility of both populations. The spin-lattice relaxation time of water in these polymer-water systems showed a deviation from the isotropic two-state model. Dielectric relaxation data indicate that this deviation can be ascribed to variations in the relaxation time of highly mobile water caused by a change in polymer concentration. The dielectric relaxation time of highly mobile water in the gelatin system did not change with a change in polymer concentration to the extent that it did in the PEG and PVP systems. This result is consistent with a slight change in water activity of the gelatin system with increasing polymer concentration.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- S Yoshioka
- National Institute of Health Sciences, Tokyo, Japan
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Miura N, Hayashi Y, Shinyashiki N, Mashimo S. Observation of unfreezable water in aqueous solution of globule protein by microwave dielectric measurement. Biopolymers 1995. [DOI: 10.1002/bip.360360103] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Umehara T, Tominaga Y, Hikida A, Mashimo S. Study on the hydration structure of L‐xylo and D‐arabo ascorbic acid solutions by time domain reflectometry. J Chem Phys 1995. [DOI: 10.1063/1.468816] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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