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López-Santiago RF, Delgado J, Castillo R. Competition among physical, chemical, and hybrid gelation mechanisms in biopolymers. SOFT MATTER 2024; 20:2518-2531. [PMID: 38404139 DOI: 10.1039/d3sm01682j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/27/2024]
Abstract
Depending on how they form their linkages, biopolymer gelatin gels are commonly classified as physical, chemical, or hybrid; in gelatin hybrid gels, the physical and chemical crosslinking mechanisms occur simultaneously. The viscoelastic behavior of gels following different gelation processes was determined around the gel point. Their gel fractal dimensions were obtained using the BST-scaling model from large amplitude oscillatory shear results. The fractal dimension of hybrid gels is between 1.46 and 1.60, depending on the dominant crosslinking process. The main features of the Lissajous-Bowditch curves were determined for maturated gels that follow different gelation processes, and it is possible to observe the dominant gelation mechanism. The gelation kinetics process is followed by measuring the mean squared displacement (MSD) of microspheres embedded in gelatin solutions using diffusion wave spectroscopy, which in turn allows evaluating G'(ω) and G''(ω), the persistence length, and the mesh size as a function of time throughout the gelation process. The MSD, as a function of elapsed time from the start of the gelation process, follows a behavior that depends on the gelation processes. As time elapses after gelation starts, the persistence length of the unstructured, non-bonded flexible polymer sections decreases due to the formation of bonds. In the hybrid case, it is not a mixture of both processes; they are not independent when occurring simultaneously. The time evolution of the gel network's mesh size roughly follows an exponential decay.
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Affiliation(s)
- Ricky F López-Santiago
- Instituto de Física, Universidad Nacional Autónoma de México, P.O. Box 20-364, 01000, Mexico City, Mexico.
| | - Jorge Delgado
- División de Ciencias e Ingenierías, Universidad de Guanajuato, Campus León, León, Guanajuato, Mexico
| | - Rolando Castillo
- Instituto de Física, Universidad Nacional Autónoma de México, P.O. Box 20-364, 01000, Mexico City, Mexico.
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2
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Drabik J, Kozdrach R, Szczerek M. Characterization of nano-silica vegetable grease with diffusing wave spectroscopy DWS and Raman spectroscopy. Sci Rep 2023; 13:18989. [PMID: 37923748 PMCID: PMC10624914 DOI: 10.1038/s41598-023-45669-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 10/22/2023] [Indexed: 11/06/2023] Open
Abstract
The diffusing wave spectroscopy (DWS) method made it possible to identify changes in the dynamics of the free movement of particles in the grease under the influence of temperature, which changed the viscoelastic properties of the grease. Changes in the parameters determined by DWS method influenced changes in the chemical structure, which was confirmed by Raman spectroscopy, determining the integral intensity of the unsaturated to saturated bond bands found in the grease. The article presents the results of the influence of temperature on changes in the viscoelastic states of vegetable grease evaluated on the basis of properties determined by DWS (diffusing wave spectroscopy). The following parameters were used to evaluate the viscoelastic states: the intensity correlation function (ICF), the correlation function of mean square displacement (MSD), the elastic modulus G' and the viscosity modulus G″. A significant effect of temperature on changes in the microstructure of vegetable grease was observed, which was reflected in the viscoelastic parameters. The dynamics of the free movement of molecules in the grease was changed, which affected the elasticity of the system and the displacement of the G' and G″ modules towards higher frequencies.
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Affiliation(s)
- Jolanta Drabik
- Bioeconomy and Ecoinnovation Department, Lukasiewicz Research Network - Institute for Sustainable Technologies, 26-600, Radom, Poland
| | - Rafal Kozdrach
- Bioeconomy and Ecoinnovation Department, Lukasiewicz Research Network - Institute for Sustainable Technologies, 26-600, Radom, Poland.
| | - Marian Szczerek
- Tribology Department, Lukasiewicz Research Network - Institute for Sustainable Technologies, 26-600, Radom, Poland
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Schirra DS, Jeziorowski S, Lehmann M, Thiele CM. Thermoreversible Gelation of Homopolyglutamates PBPMLG, PBPELG, and PBPHLG: Another Step toward de Novo RDC-Based Structure Elucidation. Macromolecules 2022. [DOI: 10.1021/acs.macromol.2c00176] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Dominic S. Schirra
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technical University of Darmstadt, 64287 Darmstadt, Germany
| | - Sharon Jeziorowski
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technical University of Darmstadt, 64287 Darmstadt, Germany
| | - Matthias Lehmann
- Institute for Organic Chemistry, University of Würzburg, 97074 Würzburg, Germany
| | - Christina M. Thiele
- Clemens-Schöpf-Institute for Organic Chemistry and Biochemistry, Technical University of Darmstadt, 64287 Darmstadt, Germany
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4
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Xu Y, Jacquat RPB, Shen Y, Vigolo D, Morse D, Zhang S, Knowles TPJ. Microfluidic Templating of Spatially Inhomogeneous Protein Microgels. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2020; 16:e2000432. [PMID: 32529798 DOI: 10.1002/smll.202000432] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 04/20/2020] [Accepted: 05/18/2020] [Indexed: 05/20/2023]
Abstract
3D scaffolds in the form of hydrogels and microgels have allowed for more native cell-culture systems to be developed relative to flat substrates. Native biological tissues are, however, usually spatially inhomogeneous and anisotropic, but regulating the spatial density of hydrogels at the microscale to mimic this inhomogeneity has been challenging to achieve. Moreover, the development of biocompatible synthesis approaches for protein-based microgels remains challenging, and typical gelation conditions include UV light, extreme pH, extreme temperature, or organic solvents, factors which can compromise the viability of cells. This study addresses these challenges by demonstrating an approach to fabricate protein microgels with controllable radial density through microfluidic mixing and physical and enzymatic crosslinking of gelatin precursor molecules. Microgels with a higher density in their cores and microgels with a higher density in their shells are demonstrated. The microgels have robust stability at 37 °C and different dissolution rates through enzymolysis, which can be further used for gradient scaffolds for 3D cell culture, enabling controlled degradability, and the release of biomolecules. The design principles of the microgels could also be exploited to generate other soft materials for applications ranging from novel protein-only micro reactors to soft robots.
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Affiliation(s)
- Yufan Xu
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Raphaël P B Jacquat
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
| | - Yi Shen
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Daniele Vigolo
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - David Morse
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Bethesda, MD, 20892, USA
| | - Shuyuan Zhang
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
| | - Tuomas P J Knowles
- Centre for Misfolding Diseases, Department of Chemistry, University of Cambridge, Cambridge, CB2 1EW, UK
- Cavendish Laboratory, University of Cambridge, Cambridge, CB3 0HE, UK
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Hong W, Xu G, Ou X, Sun W, Wang T, Tong Z. Colloidal probe dynamics in gelatin solution during the sol-gel transition. SOFT MATTER 2018; 14:3694-3703. [PMID: 29611569 DOI: 10.1039/c7sm02556d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The dynamics of the colloidal probes in a gelatin solution during the time-dependent sol-gel transition was investigated by multi-particle tracking. The relationship between the relaxation of the medium at the critical gel point and the mean square displacement of the probes was elucidated. Based on this understanding, the critical gel point of gelatin and the corresponding critical exponent n were unambiguously determined by the loss angle criterion and the time-cure superposition. The shift factors of the latter are further used to estimate the time/length-scale evolution of the gelatin during the sol-gel transition. The growth of the medium length scale crossed with the two measuring length scales successively at the pre-gel regime. Coinciding with the length-scale crossovers, the probability density function (PDF) of the probe displacements displayed two transient peaks of non-Gaussianity. In the post-gel regime, the third peak of Gaussianity suggested inhomogeneity in the gel network. The non-Gaussianity results from the bifurcation of diffusivity. The present work showed that the non-Gaussian dynamics of the probes are not the direct equivalence of that of the medium, but an effect of length-scale coupling.
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Affiliation(s)
- Wei Hong
- Research Institute of Materials Science, South China University of Technology, Guangzhou, 510640, P. R. China.
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Derkatch S, Kolotova D, Milyaeva O, Noskov B. Dynamic properties of gelatin/surfactant adsorption layers. Colloids Surf A Physicochem Eng Asp 2016. [DOI: 10.1016/j.colsurfa.2016.08.046] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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7
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Horinaka JI, Okamoto A, Takigawa T. Rheological properties of concentrated solutions of gelatin in an ionic liquid 1-ethyl-3-methylimidazolium dimethyl phosphate. Int J Biol Macromol 2016; 91:789-93. [PMID: 27311506 DOI: 10.1016/j.ijbiomac.2016.06.032] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 06/11/2016] [Accepted: 06/11/2016] [Indexed: 11/25/2022]
Abstract
Rheological properties of gelatin solutions were examined in concentrated regions. Gelatin species from porcine skin and from bovine bone were dissolved in an ionic liquid 1-ethyl-3-methylimidazolium dimethyl phosphate. The dynamic viscoelasticity data for the solutions exhibited rubbery plateaus, indicating the existence of entanglement coupling between gelatin chains in the solutions. From the analogy with rubber elasticity, assuming that the molecular weight between entanglements (Me) is the average mesh size of the entanglement network, Me for gelatin in the solutions were determined from the heights of the rubbery plateaus. Then the value of Me in the molten state (Me,melt), a material constant reflecting the chemical structure of polymer species, for gelatin was estimated to be 8.7×10(3). Compared to synthetic polyamides whose Me,melt were known, Me,melt for gelatin was significantly larger, which could be explained by the densely repeating amide bonds composing gelatin.
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Affiliation(s)
- Jun-Ichi Horinaka
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510, Japan.
| | - Arisa Okamoto
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510, Japan
| | - Toshikazu Takigawa
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo, Kyoto 615-8510, Japan
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8
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Liu S, Chan WL, Li L. Rheological Properties and Scaling Laws of κ-Carrageenan in Aqueous Solution. Macromolecules 2015. [DOI: 10.1021/acs.macromol.5b01922] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sijun Liu
- School of Mechanical and Aerospace
Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Wai Luen Chan
- School of Mechanical and Aerospace
Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Lin Li
- School of Mechanical and Aerospace
Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
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9
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Zhang H, Ding J. Frequency- and Temperature-Dependent Rheological Properties of an Amphiphilic Block Co-polymer in Water and Including Cell-Culture Media. JOURNAL OF BIOMATERIALS SCIENCE-POLYMER EDITION 2012; 21:253-69. [DOI: 10.1163/156856209x415747] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- Huan Zhang
- a Key Laboratory of Molecular Engineering of Polymers of Ministry of Education, Department of Macromolecular Science, Advanced Materials Laboratory, Fudan University, Shanghai 200433, P. R. China
| | - Jiandong Ding
- b Key Laboratory of Molecular Engineering of Polymers of Ministry of Education, Department of Macromolecular Science, Advanced Materials Laboratory, Fudan University, Shanghai 200433, P. R. China;,
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10
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Rusli A, Cook W, Liang GG. Allylic monomers as reactive plasticizers of polyphenylene oxide. Part I: Uncured systems. Eur Polym J 2011. [DOI: 10.1016/j.eurpolymj.2011.05.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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11
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Guo Y, Zhou J, Zhang L. Dynamic Viscoelastic Properties of Cellulose Carbamate Dissolved in NaOH Aqueous Solution. Biomacromolecules 2011; 12:1927-34. [DOI: 10.1021/bm200331g] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yi Guo
- Department of Chemistry, Wuhan University, Wuhan 430072, China
| | - Jinping Zhou
- Department of Chemistry, Wuhan University, Wuhan 430072, China
| | - Lina Zhang
- Department of Chemistry, Wuhan University, Wuhan 430072, China
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12
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Burey P, Bhandari B, Rutgers R, Halley P, Torley P. Confectionery Gels: A Review on Formulation, Rheological and Structural Aspects. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2009. [DOI: 10.1080/10942910802223404] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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13
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Ma C, Du W, Chen H, Liu Z, Qin Z, Pan D. Influences of nonsolvent and temperature on critical viscoelastic behaviors of ternary polyacrylonitrile solutions around the sol-gel threshold. ACTA ACUST UNITED AC 2008. [DOI: 10.1002/polb.21600] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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Gornall JL, Terentjev EM. Helix-coil transition of gelatin: helical morphology and stability. SOFT MATTER 2008; 4:544-549. [PMID: 32907218 DOI: 10.1039/b713075a] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
By combining optical rotation with thermal characterization and rheological measurements, we have studied triple helix formation in water and ethylene glycol solutions of gelatin. We find the enthalpy change per unit helix required for the transition from triple helix to random coil is independent of the concentration of helices in solution and the temperature at which the helices form. Helices formed in ethylene glycol are less stable than those formed in water solutions as, unlike water, ethylene glycol is too large a molecule to mediate interchain hydrogen bonds. The storage modulus has a universal dependence on helix concentration in both solvents but, due to a reduction in helix length, the critical concentration at which an elastic gel forms is smaller in ethylene glycol.
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Affiliation(s)
- Joanne L Gornall
- Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge, UKCB3 0HE
| | - Eugene M Terentjev
- Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge, UKCB3 0HE
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15
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Matsunaga T, Shibayama M. Gel point determination of gelatin hydrogels by dynamic light scattering and rheological measurements. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2007; 76:030401. [PMID: 17930188 DOI: 10.1103/physreve.76.030401] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2007] [Indexed: 05/19/2023]
Abstract
The sol-gel transition of gelatin aqueous solutions has been investigated in terms of time-resolved dynamic light scattering (DLS) and rheological measurements during the cooling process. A drastic increase in the scattering intensity, ergodic-nonergodic transition, and a power-law behavior in the scattering intensity-time correlation function were observed at the gelation temperature Tgel. Thus obtained "microscopic" Tgel was confirmed to be in good agreement with a "macroscopic" Tgel obtained by rheological measurements irrespective of gelatin concentration C . The fractal exponent Dp evaluated by DLS was found to be q and C independent and was also in good agreement with that obtained by rheology (n), i.e., Dp congruent with n congruent with 0.73, where q is the magnitude of the scattering vector.
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Affiliation(s)
- Takuro Matsunaga
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, 277-8581, Japan
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16
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Lu L, Liu X, Tong Z, Gao Q. Critical exponents and self-similarity for sol-gel transition in aqueous alginate systems induced by in situ release of calcium cations. J Phys Chem B 2007; 110:25013-20. [PMID: 17149924 DOI: 10.1021/jp060155e] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The sol-gel transition in aqueous alginate systems induced by in situ released calcium cations was monitored with rheology methods. Four alginate samples with different molecular weights and M/G ratios were used over the concentration C(Alg) of 2 approximately 6 wt % with different mole ratios f of Ca2+ to the alginate repeat unit. The scaling for the zero shear viscosity eta(0) before the gel point and the equilibrium modulus Ge after the gel point was described as eta(0) approximately epsilon(-k) and Ge approximately epsilon(z), respectively, where the relative distance to the gel point f(gel) was epsilon = (/f-f(gel)/)/f(gel). The relaxation critical exponent n was determined with Winter's criterion, and the critical exponents k and z estimated respectively from independent measurements of eta(0) and Ge gave n from z/(k + z). Before the gel point, the storage and loss moduli G' and G'' obtained at various epsilon can be superposed fairly well to form the master curve. The critical exponents n, k, and z were also evaluated from the shift factors and the structure self-similarity was found in the critical gel. The critical exponents evaluated with different methods agreed well with each other, suggesting two categories of the gelation as growth and cross-link. For the alginate with lower molecular weight, the critical exponents were almost independent of alginate concentration and close to the percolation prediction. For the alginate with higher molecular weight, the critical exponents, however, changed with alginate sample and concentration. The relative alginate concentration C(Alg)/C(Alg)* was found to serve as a criterion to divide these two transitions.
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Affiliation(s)
- Lu Lu
- Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, China
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17
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Mohanty B, Aswal VK, Kohlbrecher J, Bohidar HB. Length scale hierarchy in sol, gel, and coacervate phases of gelatin. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/polb.20783] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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18
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Mohanty B, Bohidar HB. Microscopic structure of gelatin coacervates. Int J Biol Macromol 2005; 36:39-46. [PMID: 15896839 DOI: 10.1016/j.ijbiomac.2005.03.012] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2004] [Revised: 03/16/2005] [Accepted: 03/21/2005] [Indexed: 11/29/2022]
Abstract
Microscopic structure of simple coacervates of gelatin having concentration approximately 130 g/l were studied at 25 degrees C by atomic force microscopy (AFM), rheology, small angle neutron scattering (SANS), UV absorption and circular dichroism (CD) techniques. The behavior of viscoelastic exponents Delta' and Delta'' of storage and loss modulii (G'(omega) approximately omega Delta', G''(omega) approximately omega Delta") revealed that, Delta' = 0.25+/-0.01 and Delta'' = 0.78+/-0.1 for coacervates. The mass fractal dimension 'd(f)' for coacervate was found to be 2.27, which attributed a compact heterogeneous network structure to the coacervates. This is supported by AFM pictures. The CD and UV absorption data indicated presence of helical structures inside the coacervates phase. SANS results showed the existence of a single length scale associated with this system identified as gelatin persistence length, zeta = 27+/-2 A. These studies indicate that the coacervate phase is a low dimensional dense heterogeneous material comprised of strongly interconnected triple helices which imparts a large storage modulus to this material.
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Affiliation(s)
- Biswaranjan Mohanty
- School of Physical Sciences, Jawaharlal Nehru University, New Delhi 110067, India
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19
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Lu L, Liu X, Dai L, Tong Z. Difference in Concentration Dependence of Relaxation Critical Exponent n for Alginate Solutions at Sol−Gel Transition Induced by Calcium Cations. Biomacromolecules 2005; 6:2150-6. [PMID: 16004457 DOI: 10.1021/bm050126u] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The sol-gel transition in aqueous alginate solutions induced by chelation with calcium cations from in situ release has been investigated with viscoelastic methods. Two alginate samples having different molecular weights (MW) were used over the concentration C(Alg) of 2 approximately 6 wt % with different mole ratio f of Ca2+ to the alginate repeat unit. The gel point f(gel) and relaxation critical exponent n were determined according to Winter's criterion, the later agrees well with that obtained from the relaxation modulus. The results indicate that the power law is valid for the dynamic relaxation at the gel point and the critical gel possesses the self-similarity in structure. With increasing C(Alg), f(gel) for the alginate with lower MW decreases dramatically and n is almost constant of about 0.71. In contrast, f(gel) for the higher MW alginate with is almost a constant and n decreases from 0.72 then levels off at 0.37 with increasing C(Alg), indicating that the concentration dependence of n varies with MW of alginate in the starting solution. The fractal dimension d(f) estimated from n suggests a denser structure in the critical gel of higher MW alginate. Either n or d(f) has been found to follow one curve for the two samples if plotted against the number of cross-link junctions per polymer chain, which is proportional to the alginate MW.
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Affiliation(s)
- Lu Lu
- Research Institute of Materials Science, South China University of Technology, Guangzhou 510640, China
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20
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Brayner R, Coradin T, Vaulay MJ, Mangeney C, Livage J, Fiévet F. Preparation and characterization of metal (Au)– and bimetallic alloys (AuNi)–gelatin nanocomposites. Colloids Surf A Physicochem Eng Asp 2005. [DOI: 10.1016/j.colsurfa.2005.01.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Coradin T, Bah S, Livage J. Gelatine/silicate interactions: from nanoparticles to composite gels. Colloids Surf B Biointerfaces 2005; 35:53-8. [PMID: 15261056 DOI: 10.1016/j.colsurfb.2004.02.008] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2004] [Indexed: 11/25/2022]
Abstract
The possibility to design new composites associating biopolymers with mineral phases relies on the understanding and control of their mutual interactions. In this work, aqueous solutions of gelatine and sodium silicate were mixed at pH 5, 37 degrees C and left to stand at 20 degrees C for 1 day. At low gelatine and high silicate contents, precipitates were obtained, containing a fixed silicon/polymer molar ratio. Scanning electron microscopy (SEM) reveals that they are formed of large aggregates of platelets, constituted of closely-packed nanoparticles. For high gelatine contents, composite gels were formed consisting of silica particles dispersed in the biopolymer matrix. Swelling studies indicate that the addition of silica decreases the stability of the gels by inducing gelatine depletion in solution. Similar experiments conducted at pH 7 show that at this pH, silicates are more effective at precipitating gelatine. A model is proposed for the formation of the composites, based on the electrostatic interactions arising between silicates and polymer chains. These results are discussed in the context of hybrid biomaterials design and biosilicification processes.
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Affiliation(s)
- Thibaud Coradin
- Laboratoire de Chimie de la Matière Condensée, Université Pierre et Marie Curie, CNRS-UMR 7574, 4 place Jussieu, F-75252 Paris Cedex 05, France.
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22
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Shibayama M, Norisuye T. Gel Formation Analyses by Dynamic Light Scattering. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2002. [DOI: 10.1246/bcsj.75.641] [Citation(s) in RCA: 136] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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23
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Okamoto M, Norisuye T, Shibayama M. Time-Resolved Dynamic Light Scattering Study on Gelation and Gel-Melting Processes of Gelatin Gels. Macromolecules 2001. [DOI: 10.1021/ma010734b] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Masahiko Okamoto
- Department of Polymer Science & Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Tomohisa Norisuye
- Department of Polymer Science & Engineering, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
| | - Mitsuhiro Shibayama
- Neutron Scattering Laboratory, Institute for Solid State Physics, The University of Tokyo, Tokai, Naka-gun, Ibaraki 319-1106, Japan
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24
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Shibayama M, Okamoto M. Dynamic light scattering study on gelatin aqueous solutions and gels. J Chem Phys 2001. [DOI: 10.1063/1.1391257] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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25
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26
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Cirkel PA, Okada T. A Comparison of Mechanical and Electrical Percolation during the Gelling of Nafion Solutions. Macromolecules 2000. [DOI: 10.1021/ma992031o] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Peter A. Cirkel
- National Institute of Materials and Chemical Research, Tsukuba, Ibaraki 305-8565, Japan
| | - Tatsuhiro Okada
- National Institute of Materials and Chemical Research, Tsukuba, Ibaraki 305-8565, Japan
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Li L, Uchida H, Aoki Y, Yao ML. Rheological Images of Poly(vinyl chloride) Gels. 2. Divergence of Viscosity and the Scaling Law before the Sol−Gel Transition. Macromolecules 1997. [DOI: 10.1021/ma971189a] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Lin Li
- Chemical Science Laboratories, Mitsubishi Chemical Corporation, 1, Toho-cho, Yokkaichi-City, Mie 510, Japan
| | - Hisao Uchida
- Chemical Science Laboratories, Mitsubishi Chemical Corporation, 1, Toho-cho, Yokkaichi-City, Mie 510, Japan
| | - Yuji Aoki
- Chemical Science Laboratories, Mitsubishi Chemical Corporation, 1, Toho-cho, Yokkaichi-City, Mie 510, Japan
| | - Ming Long Yao
- Rheometric Scientific F. E. Ltd., 2−19−6, Yanagibashi, Taito-ku, Tokyo 111, Japan
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Li L, Aoki Y. Rheological Images of Poly(vinyl chloride) Gels. 1. The Dependence of Sol−Gel Transition on Concentation. Macromolecules 1997. [DOI: 10.1021/ma971045w] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Lin Li
- Chemical Science Laboratories, Mitsubishi Chemical Corporation, 1, Toho-cho, Yokkaichi-City, Mie 510, Japan
| | - Yuji Aoki
- Chemical Science Laboratories, Mitsubishi Chemical Corporation, 1, Toho-cho, Yokkaichi-City, Mie 510, Japan
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