1
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Macias-Rodriguez BA, Gouzy R, Coulais C, Velikov KP. Thermoresponsive oil-continuous gels based on double-interpenetrating colloidal-particle networks. SOFT MATTER 2024; 20:3033-3043. [PMID: 38389496 DOI: 10.1039/d3sm01582c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Gels composed of multicomponent building blocks offer promising opportunities for the development of novel soft materials with unique and useful structures. While interpenetrating polymer networks have been extensively studied and applied in the creation of these gels, equivalent strategies utilizing colloidal particles have received limited scientific and technological attention. This study presents a novel class of thermo-responsive apolar double gels from interpenetrating networks of attractive colloidal silica and lipid particles. These double gels are easily assembled and suitable for the fabrication of 3D-printed edible soft constructs. Emphasis is focused on the rheological properties and structure emerging on the dilute regime (ϕ ≲ 0.1). Rheological investigations demonstrate that double gels exhibit greater stiffness and resilience to yielding compared to their single lipid gel counterparts. The scaling behavior of the oscillatory linear shear moduli and the critical strain for yielding with volume fraction remain comparable between single and double gels. Creep yielding in double gels exhibits two exponential decay regimes, suggesting the presence of thicker gel strands undergoing flow. Visualization and quantification of the quiescent microstructure confirms the existence of such denser aggregates devoid of larger clusters due to steric hindrance of interpenetrating networks in double gels. This is in stark contrast to lipid single gels where aggregates grow unrestrictedly into larger clusters. Our study constitutes the first demonstration on the assembly of apolar double gel networks as a promising avenue for the design of novel soft materials and foods with tailored structure and mechanics.
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Affiliation(s)
- Braulio A Macias-Rodriguez
- Unilever Innovation Center Wageningen, Bronland 14, 6708 WH Wageningen, The Netherlands.
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Roland Gouzy
- Unilever Innovation Center Wageningen, Bronland 14, 6708 WH Wageningen, The Netherlands.
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Corentin Coulais
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Krassimir P Velikov
- Unilever Innovation Center Wageningen, Bronland 14, 6708 WH Wageningen, The Netherlands.
- Institute of Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
- Soft Condensed Matter, Debye Institute for Nanomaterials Science, Utrecht University, Princetonplein 5, 3584 CC Utrecht, The Netherlands
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2
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Tian W, Huang Y, Liu L, Yu Y, Cao Y, Xiao J. Tailoring the oral sensation and digestive behavior of konjac glucomannan-gelatin binary hydrogel based bigel: Effects of composition and ratio. Int J Biol Macromol 2024; 256:127963. [PMID: 37951424 DOI: 10.1016/j.ijbiomac.2023.127963] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Revised: 10/29/2023] [Accepted: 11/06/2023] [Indexed: 11/14/2023]
Abstract
In the food industry, there is a growing demand for bigels that offer both adaptable oral sensations and versatile delivery properties. Herein, we developed bigels using a binary hydrogel of konjac glucomannan (KGM) and gelatin (G) combined with a stearic acid oleogel. We closely examined how the oleogel/hydrogel volume ratio (φ) and the KGM/G mass ratio (γ) influenced various characteristics of the bigels, including their microstructure, texture, rheological properties, thermal-sensitivity, oral tribology, digestive stability, and nutraceutical delivery efficiency. A noteworthy observation was the structural evolution of the bigels with increasing φ values: transitioning from oleogel-in-hydrogel to a bicontinuous structure, and eventually to hydrogel-in-oleogel. Lower γ values yielded a softer, thermally-responsive bigel, whereas higher γ values imparted enhanced viscosity, stickiness, and spreadability to the bigel. Oral tribology assessments demonstrated that φ primarily influenced the friction sensations at lower chewing intensities. In contrast, γ played a significant role in augmenting oral friction perceptions during more intense chewing. Additionally, φ dictated the controlled release and bioaccessibility of curcumin, while γ determined digestive stability. This study provides valuable insights, emphasizing that through meticulous selection and adjustment of the hydrogel matrix composition, bigels can be custom-fabricated to achieve specific oral sensations and regulated digestive behaviors.
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Affiliation(s)
- Wenni Tian
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods, College of Food Science, South China Agricultural University, Guangzhou 510642, China
| | - Yushu Huang
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods, College of Food Science, South China Agricultural University, Guangzhou 510642, China
| | - Lang Liu
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods, College of Food Science, South China Agricultural University, Guangzhou 510642, China
| | - Yuanshan Yu
- Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing, Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Sericultural & Argi-Food Research Institute, Guangzhou 510610, China
| | - Yong Cao
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods, College of Food Science, South China Agricultural University, Guangzhou 510642, China
| | - Jie Xiao
- Guangdong Provincial Key Laboratory of Nutraceuticals and Functional Foods, College of Food Science, South China Agricultural University, Guangzhou 510642, China.
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3
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Yamamoto A, Inui T, Suzuki D, Urayama K. Stress-independent delay time in yielding of dilute colloidal gels. SOFT MATTER 2023; 19:9082-9091. [PMID: 37987474 DOI: 10.1039/d3sm01238g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
We investigate the yielding under shear for dilute poly(N-isopropyl acrylamide-co-fumaric acid) (PNIPAM-FAc) colloidal gels obtained above the volume phase transition temperature. In this temperature range, the microgel suspensions form colloidal gels due to hydrophobic interparticle interactions under appropriate pH and ionic strength conditions. Step-strain tests revealed that yielding occurs when the applied strain exceeds a specific threshold, requiring a finite, stress-independent delay time (tD). This is distinct from previous findings on delayed yielding in other colloidal gels, where tD decreases with increasing stress. In the start-up shear tests, yield strain (γy) at a higher strain rate () increases with escalating , while γy at lower remains constant. This characteristic γy- relationship is successfully explained by a simple model using the stress-independent tD value without an adjustable fitting parameter. The distinctive yielding behavior, underscored by a stress-independent tD, is expected to originate from strain-induced macroscopic phase separation into a dense colloidal gel and water, observable separately from rheological measurements.
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Affiliation(s)
- Atsushi Yamamoto
- Department of Macromolecular Science and Engineering, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585, Japan
| | - Takumi Inui
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan.
| | - Daisuke Suzuki
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan.
- Research Initiative for Supra-Materials, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Ueda 386-8567, Japan
| | - Kenji Urayama
- Department of Material Chemistry, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan.
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4
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Morozova SM, Gevorkian A, Kumacheva E. Design, characterization and applications of nanocolloidal hydrogels. Chem Soc Rev 2023. [PMID: 37464914 DOI: 10.1039/d3cs00387f] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
Nanocolloidal gels (NCGs) are an emerging class of soft matter, in which nanoparticles act as building blocks of the colloidal network. Chemical or physical crosslinking enables NCG synthesis and assembly from a broad range of nanoparticles, polymers, and low-molecular weight molecules. The synergistic properties of NCGs are governed by nanoparticle composition, dimensions and shape, the mechanism of nanoparticle bonding, and the NCG architecture, as well as the nature of molecular crosslinkers. Nanocolloidal gels find applications in soft robotics, bioengineering, optically active coatings and sensors, optoelectronic devices, and absorbents. This review summarizes currently scattered aspects of NCG formation, properties, characterization, and applications. We describe the diversity of NCG building blocks, discuss the mechanisms of NCG formation, review characterization techniques, outline NCG fabrication and processing methods, and highlight most common NCG applications. The review is concluded with the discussion of perspectives in the design and development of NCGs.
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Affiliation(s)
- Sofia M Morozova
- N.E. Bauman Moscow State Technical University, 5/1 2-nd Baumanskaya street, 105005, Moscow, Russia
- Department of Chemistry University of Toronto, 80 Saint George street, Toronto, Ontario M5S 3H6, Canada.
| | - Albert Gevorkian
- Department of Chemistry University of Toronto, 80 Saint George street, Toronto, Ontario M5S 3H6, Canada.
| | - Eugenia Kumacheva
- Department of Chemistry University of Toronto, 80 Saint George street, Toronto, Ontario M5S 3H6, Canada.
- Department of Chemical Engineering and Applied Chemistry University of Toronto, 200 College street, Toronto, Ontario M5S 3E5, Canada
- The Institute of Biomaterials and Biomedical Engineering University of Toronto, 4 Taddle Creek Road, Toronto, Ontario M5S 3G9, Canada
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5
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Petrunin AV, Schmidt MM, Schweins R, Houston JE, Scotti A. Self-Healing of Charged Microgels in Neutral and Charged Environments. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023. [PMID: 37220302 DOI: 10.1021/acs.langmuir.2c03054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The softness of microgels depends on many aspects, such as particle characteristic lengths, sample concentration, chemical composition of the sample, and elastic moduli of the particle. Here, the response to crowding of ionic microgels is studied. Charged and uncharged ionic microgels are studied in concentrated suspensions of both neutral and ionic microgels with the same swollen size. The combination of small-angle X-ray and neutron scattering with contrast variation allows us to probe both the particle-to-particle arrangement and the response of individual ionic microgels to crowding. When the ionic microgels are uncharged, initial isotropic deswelling followed by faceting is observed. Therefore, the ionizable groups in the polymeric network do not affect the response of the ionic microgel to crowding, which is similar to what has been reported for neutral microgels. In contrast, the kind of microgels composing the matrix plays a key role once the ionic microgels are charged. If the matrix is composed of neutral microgels, a pronounced faceting and negligible deswelling is observed. When only charged ionic microgels are present in the suspension, isotropic deswelling without faceting is dominant.
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Affiliation(s)
- Alexander V Petrunin
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074 Aachen, Germany
| | - Maximilian M Schmidt
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074 Aachen, Germany
| | - Ralf Schweins
- Institut Laue-Langevin ILL, DS/LSS, 71 Avenue des Martyrs, F-38000 Grenoble, France
| | - Judith E Houston
- European Spallation Source ERIC, Box 176, SE-221 00 Lund, Sweden
| | - Andrea Scotti
- Institute of Physical Chemistry, RWTH Aachen University, Landoltweg 2, 52074 Aachen, Germany
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6
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McDonald MN, Zhu Q, Paxton WF, Peterson CK, Tree DR. Active control of equilibrium, near-equilibrium, and far-from-equilibrium colloidal systems. SOFT MATTER 2023; 19:1675-1694. [PMID: 36790855 DOI: 10.1039/d2sm01447e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The development of top-down active control over bottom-up colloidal assembly processes has the potential to produce materials, surfaces, and objects with applications in a wide range of fields spanning from computing to materials science to biomedical engineering. In this review, we summarize recent progress in the field using a taxonomy based on how active control is used to guide assembly. We find there are three distinct scenarios: (1) navigating kinetic pathways to reach a desirable equilibrium state, (2) the creation of a desirable metastable, kinetically trapped, or kinetically arrested state, and (3) the creation of a desirable far-from-equilibrium state through continuous energy input. We review seminal works within this framework, provide a summary of important application areas, and present a brief introduction to the fundamental concepts of control theory that are necessary for the soft materials community to understand this literature. In addition, we outline current and potential future applications of actively-controlled colloidal systems, and we highlight important open questions and future directions.
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Affiliation(s)
- Mark N McDonald
- Department of Chemical Engineering, Brigham Young University, Provo, Utah, USA.
| | - Qinyu Zhu
- Department of Chemical Engineering, Brigham Young University, Provo, Utah, USA.
| | - Walter F Paxton
- Department of Chemistry and Biochemistry, Brigham Young University, Provo, Utah, USA
| | - Cameron K Peterson
- Department of Electrical and Computer Engineering, Brigham Young University, Provo, Utah, USA
| | - Douglas R Tree
- Department of Chemical Engineering, Brigham Young University, Provo, Utah, USA.
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7
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Chen Y, Zhang Q, Ramakrishnan S, Leheny RL. Memory in aging colloidal gels with time-varying attraction. J Chem Phys 2023; 158:024906. [PMID: 36641382 DOI: 10.1063/5.0126432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We report a combined rheology, x-ray photon correlation spectroscopy, and modeling study of gel formation and aging in suspensions of nanocolloidal spheres with volume fractions of 0.20 and 0.43 and with a short-range attraction whose strength is tuned by changing temperature. Following a quench from high temperature, where the colloids are essentially hard spheres, to a temperature below the gel point, the suspensions form gels that undergo aging characterized by a steadily increasing elastic shear modulus and slowing, increasingly constrained microscopic dynamics. The aging proceeds at a faster rate for stronger attraction strength. When the attraction strength is suddenly lowered during aging, the gel properties evolve non-monotonically in a manner resembling the Kovacs effect in glasses, in which the modulus decreases and the microscopic dynamics become less constrained for a period before more conventional aging resumes. Eventually, the properties of the gel following the decrease in attraction strength converge to those of a gel that has undergone aging at the lower attraction strength throughout. The time scale of this convergence increases as a power law with the age at which the attraction strength is decreased and decreases exponentially with the magnitude of the change in attraction. A model for gel aging in which particles attach and detach from the gel at rates that depend on their contact number reproduces these trends and reveals that the non-monotonic behavior results from the dispersion in the rates that the populations of particles with different contact number adjust to the new attraction strength.
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Affiliation(s)
- Yihao Chen
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Qingteng Zhang
- X-Ray Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - Subramanian Ramakrishnan
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Tallahassee, Florida 32310, USA
| | - Robert L Leheny
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
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8
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Fussell SL, Royall CP, van Duijneveldt JS. Controlling Kinetic Pathways in Demixing Microgel-Micelle Mixtures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:1010-1018. [PMID: 36621908 PMCID: PMC9878723 DOI: 10.1021/acs.langmuir.2c02583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/22/2022] [Indexed: 06/17/2023]
Abstract
We investigate the temperature-dependent phase behavior of mixtures of poly(N-isopropylacrylamide) (pNIPAM) microgel colloids and a triblock copolymer (PEO-PPO-PEO) surfactant. Usually, gelation in these systems results from an increase in temperature. Here we investigate the role of the heating rate, and surprisingly, we find that this causes the mechanism of aggregation to change from one which is driven by depletion of the microgels by the micelles at low temperatures to the association of the two species at high temperatures. We thus reveal two competing mechanisms for attractions between the microgel particles which can be controlled by changing the heating rate. We use this heating-rate-dependent response of the system to access multiple structures for the same system composition. Samples were found to demix into phases rich and poor in microgel particles at temperatures below 33 °C, under conditions where the microgels particles are partially swollen. Under rapid heating full demixing is bypassed, and gel networks are formed instead. The temperature history of the sample, therefore, allows for kinetic selection between different final structures, which may be metastable.
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Affiliation(s)
- S. L. Fussell
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
- Bristol
Centre for Functional Nanomaterials, University
of Bristol, Tyndall Avenue, Bristol BS8 1TL, U.K.
| | - C. P. Royall
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K.
- Bristol
Centre for Functional Nanomaterials, University
of Bristol, Tyndall Avenue, Bristol BS8 1TL, U.K.
- Gulliver
UMR CNRS 7083, ESPCI Paris, Université
PSL, 75005 Paris, France
- HH
Wills Physics Laboratory, University of
Bristol, Tyndall Avenue, Bristol BS8 1TL, U.K.
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9
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Lu CH, Yeh YC. Synthesis and Processing of Dynamic Covalently Crosslinked Polydextran/Carbon Dot Nanocomposite Hydrogels with Tailorable Microstructures and Properties. ACS Biomater Sci Eng 2022; 8:4289-4300. [PMID: 36075100 DOI: 10.1021/acsbiomaterials.2c00873] [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
Using functionalized nanoparticles to crosslink hydrophilic polymers is a growing theme of directly constructing nanocomposite (NC) hydrogels. Employing dynamic covalent chemistry at the nanoparticle-polymer interface is particularly attractive due to the spontaneous formation and reversible manner of dynamic covalent bonds. However, the structure and property modulation of the dynamic covalently crosslinked NC hydrogels has not been thoroughly discussed. Here, we fabricated NC hydrogels by using amine-functionalized carbon dots (CDs) to crosslink polydextran aldehyde (PDA) polymers through imine bond formation. The role of PDA with different oxidation degrees (i.e., PDA10, PDA30, and PDA50) in affecting the microstructures and properties of PDA@CD hydrogels was systematically investigated, showing that the PDA50@CD hydrogel presented the densest structure and the highest mechanical strength among the three PDA@CD hydrogels. The pH-responsiveness, 3D printing, electrospinning, and biocompatibility of PDA@CD hydrogels were also demonstrated, showing the great promise of using PDA@CD hydrogels for applications in biomedicine and biofabrication.
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Affiliation(s)
- Cheng-Hsun Lu
- Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Yi-Cheun Yeh
- Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617, Taiwan
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10
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Lu CH, Yeh YC. Fabrication of Multiresponsive Magnetic Nanocomposite Double-Network Hydrogels for Controlled Release Applications. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2105997. [PMID: 34791796 DOI: 10.1002/smll.202105997] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Nanocomposite double-network hydrogels (ncDN hydrogels) have been demonstrated as promising biomaterials to present several desired properties (e.g., high mechanical strength, stimuli-responsiveness, and local therapy) for biomedicine. Here, a new type of ncDN hydrogels featuring definable microstructures and properties as well as multistimuli responsiveness for controlled release applications is developed. Amine-functionalized iron oxide nanoparticles (IOPs_NH2 ) are used as nanoparticle cross-linkers to simultaneously connect the dual networks of gelatin (Gel) and polydextran aldehyde (PDA) through hydrogen bonding, electrostatic interactions, and dynamic imine bonds. The pH- and temperature-responsive Gel/PDA/IOP_NH2 ncDN hydrogels present a fast release profile of proteins at acidic pH and high temperature. Besides, IOP_NH2 also contributes the magnetic-responsiveness to the ncDN hydrogels, allowing the use of magnetic field to generate heat to facilitate the structural change of hydrogels and the subsequent applications. Taken together, a versatile ncDN hydrogel platform capable of multistimuli responsiveness and local heating for controlled release is developed for advanced biomedical applications.
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Affiliation(s)
- Cheng-Hsun Lu
- Institute of Polymer Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan
| | - Yi-Cheun Yeh
- Institute of Polymer Science and Engineering, National Taiwan University, Taipei, 10617, Taiwan
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11
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Dang S, Brady J, Rel R, Surineni S, O'Shaughnessy C, McGorty R. Core-shell droplets and microcapsules formed through liquid-liquid phase separation of a colloid-polymer mixture. SOFT MATTER 2021; 17:8300-8307. [PMID: 34550150 DOI: 10.1039/d1sm01091c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Microcapsules allow for the controlled containment, transport, and release of cargoes ranging from pharmaceuticals to fragrances. Given the interest from a variety of industries in microcapsules and other core-shell structures, a multitude of fabrication strategies exist. Here, we report on a method relying on a mixture of temperature-responsive microgel particles, poly(N-isopropylacrylamide) (pNIPAM), and a polymer which undergo fluid-fluid phase separation. At room temperature this mixture separates into colloid-rich (liquid) and colloid-poor (gas) fluids. By heating the sample above a critical temperature where the microgel particles shrink dramatically and develop a more deeply attractive interparticle potential, the droplets of the colloid-rich phase become gel-like. As the temperature is lowered back to room temperature, these droplets of gelled colloidal particles reliquefy and phase separation within the droplet occurs. This phase separation leads to colloid-poor droplets within the colloid-rich droplets surrounded by a continuous colloid-poor phase. The gas/liquid/gas all-aqueous double emulsion lasts only a few minutes before a majority of the inner droplets escape. However, the colloid-rich shell of the core-shell droplets can solidify with the addition of salt. That this method creates core-shell structures with a shell composed of stimuli-sensitive microgel colloidal particles using only aqueous components makes it attractive for encapsulating biological materials and making capsules that respond to changes in, for example, temperature, salt concentration, or pH.
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Affiliation(s)
- Steven Dang
- Department of Physics and Biophysics, University of San Diego, San Diego, CA, 92110, USA.
| | - John Brady
- Department of Physics and Biophysics, University of San Diego, San Diego, CA, 92110, USA.
| | - Ryle Rel
- Department of Physics and Biophysics, University of San Diego, San Diego, CA, 92110, USA.
| | - Sreenidhi Surineni
- Department of Physics and Biophysics, University of San Diego, San Diego, CA, 92110, USA.
| | - Conor O'Shaughnessy
- Department of Physics and Biophysics, University of San Diego, San Diego, CA, 92110, USA.
| | - Ryan McGorty
- Department of Physics and Biophysics, University of San Diego, San Diego, CA, 92110, USA.
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12
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Ríos de Anda I, Coutable-Pennarun A, Brasnett C, Whitelam S, Seddon A, Russo J, Anderson JLR, Royall CP. Decorated networks of native proteins: nanomaterials with tunable mesoscopic domain size. SOFT MATTER 2021; 17:6873-6883. [PMID: 34231559 PMCID: PMC8294043 DOI: 10.1039/d0sm02269a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 06/30/2021] [Indexed: 06/13/2023]
Abstract
Natural and artificial proteins with designer properties and functionalities offer unparalleled opportunity for functional nanoarchitectures formed through self-assembly. However, to exploit this potential we need to design the system such that assembly results in desired architecture forms while avoiding denaturation and therefore retaining protein functionality. Here we address this challenge with a model system of fluorescent proteins. By manipulating self-assembly using techniques inspired by soft matter where interactions between the components are controlled to yield the desired structure, we have developed a methodology to assemble networks of proteins of one species which we can decorate with another, whose coverage we can tune. Consequently, the interfaces between domains of each component can also be tuned, with potential applications for example in energy - or electron - transfer. Our model system of eGFP and mCherry with tuneable interactions reveals control over domain sizes in the resulting networks.
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Affiliation(s)
- Ioatzin Ríos de Anda
- H.H. Wills Physics LaboratoryTyndall AvenueBristolBS8 1TLUK
- School of Mathematics, University WalkBristolBS8 1TWUK
| | - Angélique Coutable-Pennarun
- BrisSynBio Synthetic Biology Research Centre, Life Sciences BuildingTyndall AvenueBristolBS8 1TQUK
- School of Biochemistry, University of BristolBristolBS8 1TDUK
| | | | - Stephen Whitelam
- Molecular Foundry, Lawrence Berkeley National LaboratoryBerkeleyCalifornia 94720USA
| | - Annela Seddon
- H.H. Wills Physics LaboratoryTyndall AvenueBristolBS8 1TLUK
- Bristol Centre for Functional Nanomaterials, University of BristolBristolBS8 1TLUK
| | - John Russo
- School of Mathematics, University WalkBristolBS8 1TWUK
- Dipartimento di Fisica and CNR-ISC, Sapienza-Università di RomaPiazzale A. Moro 200185 RomaItaly
| | - J. L. Ross Anderson
- School of Biochemistry, University of BristolBristolBS8 1TDUK
- School of Cellular and Molecular Medicine, University WalkBristolBS8 1TDUK
| | - C. Patrick Royall
- H.H. Wills Physics LaboratoryTyndall AvenueBristolBS8 1TLUK
- Gulliver UMR CNRS 7083, ESPCI Paris, Université PSL75005 ParisFrance
- School of Chemistry, University of BristolCantock's CloseBristolBS8 1TSUK
- Centre for Nanoscience and Quantum InformationTyndall AvenueBristolBS8 1FDUK
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13
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Roullet M, Clegg PS, Frith WJ. Rheology of protein-stabilised emulsion gels envisioned as composite networks. 2 - Framework for the study of emulsion gels. J Colloid Interface Sci 2021; 594:92-100. [PMID: 33756372 DOI: 10.1016/j.jcis.2021.02.088] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 02/18/2021] [Accepted: 02/19/2021] [Indexed: 11/30/2022]
Abstract
HYPOTHESIS The aggregation of protein-stabilised emulsions leads to the formation of emulsion gels. These soft solids may be envisioned as droplet-filled matrices. Here however, it is assumed that protein-coated sub-micron droplets contribute to the network formation in a similar way to proteins. Emulsion gels are thus envisioned as composite networks made of proteins and droplets. EXPERIMENTS Emulsion gels with a wide range of composition are prepared and their viscoelasticity and frequency dependence are measured. Their rheological behaviours are then analysed and compared with the properties of pure gels presented in the first part of this study. FINDINGS When the concentrations of droplets and protein are expressed as an effective volume fraction, the rheological behaviour of emulsion gels is shown to depend mostly on the total volume fraction, while the composition of the gel indicates its level of similarity with either pure droplet gels or pure protein gels. These results help to form an emerging picture of protein-stabilised emulsion gel as intermediate between droplet and protein gels. This justifies a posteriori the hypothesis of composite networks, and opens the road for the formulation of emulsion gels with fine-tuned rheology.
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Affiliation(s)
- Marion Roullet
- Unilever R& D Colworth, Sharnbrook, Bedford MK44 1LQ, UK; School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK.
| | - Paul S Clegg
- School of Physics and Astronomy, University of Edinburgh, Peter Guthrie Tait Road, Edinburgh EH9 3FD, UK.
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14
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Liu W, Wu J, Zhu H, He C, Ngai T. A facile evanescent-field imaging approach for monitoring colloidal gel evolution near a surface. SOFT MATTER 2021; 17:4006-4010. [PMID: 33881131 DOI: 10.1039/d1sm00331c] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A facile evanescent-field imaging approach is developed to probe the aggregation behavior of near-wall colloids/clusters during colloidal gel evolution. Total internal reflection microscope (TIRM) images are directly utilized to access the structural relaxation time via density-fluctuation theory. The behaviors of cluster-cluster aggregation and physical aging of the colloidal gel networks are resolved in both time and space under fractal scaling criteria.
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Affiliation(s)
- Wei Liu
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China. and Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China and College of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou 521041, China and Department of Chemistry, The Chinese University of Hong Kong, N.T., Shatin, Hong Kong, China.
| | - Jiahao Wu
- Department of Chemistry, The Chinese University of Hong Kong, N.T., Shatin, Hong Kong, China.
| | - Hui Zhu
- College of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou 521041, China
| | - Chuanxin He
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, China.
| | - To Ngai
- Department of Chemistry, The Chinese University of Hong Kong, N.T., Shatin, Hong Kong, China.
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15
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Cho JH, Bischofberger I. Two modes of cluster dynamics govern the viscoelasticity of colloidal gels. Phys Rev E 2021; 103:032609. [PMID: 33862797 DOI: 10.1103/physreve.103.032609] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 03/05/2021] [Indexed: 11/07/2022]
Abstract
Colloidal gels formed by strongly attractive particles at low particle volume fractions are composed of space-spanning networks of uniformly sized clusters. We study the thermal fluctuations of the clusters using differential dynamic microscopy by decomposing them into two modes of dynamics, and link them to the macroscopic viscoelasticity via rheometry. The first mode, dominant at early times, represents the localized, elastic fluctuations of individual clusters. The second mode, pronounced at late times, reflects the collective, viscoelastic dynamics facilitated by the connectivity of the clusters. By mixing two types of particles of distinct attraction strengths in different proportions, we control the transition time at which the collective mode starts to dominate, and hence tune the frequency dependence of the linear viscoelastic moduli of the binary gels.
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Affiliation(s)
- Jae Hyung Cho
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
| | - Irmgard Bischofberger
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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16
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Elastocapillary interactions of thermoresponsive microgels across the volume phase transition temperatures. J Colloid Interface Sci 2021; 584:275-280. [DOI: 10.1016/j.jcis.2020.09.085] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 12/16/2022]
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17
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Haddadi S, Skepö M, Jannasch P, Manner S, Forsman J. Building polymer-like clusters from colloidal particles with isotropic interactions, in aqueous solution. J Colloid Interface Sci 2021; 581:669-681. [DOI: 10.1016/j.jcis.2020.07.150] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 07/31/2020] [Accepted: 07/31/2020] [Indexed: 12/31/2022]
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18
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Immink JN, Bergman MJ, Maris JJE, Stenhammar J, Schurtenberger P. Crystal-to-Crystal Transitions in Binary Mixtures of Soft Colloids. ACS NANO 2020; 14:14861-14868. [PMID: 33191738 PMCID: PMC7690049 DOI: 10.1021/acsnano.0c03966] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Accepted: 11/11/2020] [Indexed: 05/31/2023]
Abstract
In this article, we demonstrate a method for inducing reversible crystal-to-crystal transitions in binary mixtures of soft colloidal particles. Through a controlled decrease of salinity and increasingly dominating electrostatic interactions, a single sample is shown to reversibly organize into entropic crystals, electrostatic attraction-dominated crystals, or aggregated gels, which we quantify using microscopy and image analysis. We furthermore analyze crystalline structures with bond order analysis to discern between two crystal phases. We observe the different phases using a sample holder geometry that allows both in situ salinity control and imaging through confocal laser scanning microscopy and apply a synthesis method producing particles with high resolvability in microscopy with control over particle size. The particle softness provides for an enhanced crystallization speed, while altering the re-entrant melting behavior as compared to hard sphere systems. This work thus provides several tools for use in the reproducible manufacture and analysis of binary colloidal crystals.
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Affiliation(s)
- Jasper N. Immink
- Division
of Physical Chemistry, Lund University, 221 00 Lund, Sweden
| | - Maxime J. Bergman
- Department
of Physics, University of Fribourg, 1700 Fribourg, Switzerland
| | - J. J. Erik Maris
- Inorganic
Chemistry and Catalysis Group, Utrecht University, 3584 CS Utrecht, The Netherlands
| | - Joakim Stenhammar
- Division
of Physical Chemistry, Lund University, 221 00 Lund, Sweden
| | - Peter Schurtenberger
- Division
of Physical Chemistry, Lund University, 221 00 Lund, Sweden
- Lund
Institute of advanced Neutron and X-ray Science (LINXS), Lund University, 221 00 Lund, Sweden
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19
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Minami S, Watanabe T, Sasaki Y, Minato H, Yamamoto A, Suzuki D, Urayama K. Two-step yielding behavior of densely packed microgel mixtures with chemically dissimilar surfaces and largely different sizes. SOFT MATTER 2020; 16:7400-7413. [PMID: 32699868 DOI: 10.1039/d0sm00366b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Steady-state flow and elastic behavior is investigated for the moderately concentrated binary suspensions of soft microgels (pastes) with chemically dissimilar surfaces, and various degrees of size- and stiffness disparities. The pastes of poly(N-isopropyl acrylamide) (N) and poly(N-isopropyl methacrylamide) (NM) microgels with different values of yield strain γc (γNc > γNMc) are employed as the components. For the single microgel pastes (φ ≈ 1 where φ is apparent volume fraction), the values of γc are governed by the chemical species of constituent polymer in microgel surface whereas γc is insensitive to cross-link density and particle size. We demonstrate that the binary N/NM pastes with large size disparity (RN/NM = DN/DNM < 0.26 where D is the microgel diameter) at low φN (φN: weight fraction of small N microgels) exhibit the peculiarities in several rheological aspects, i.e., the two-step yielding in steady-state flow, and their values of γc and equilibrium shear modulus (G0) being equivalent to those of the single large NM microgel paste. These peculiarities are attributed to the characteristic packing resulting from large size disparity in which all or almost of the small N microgels tend to be accommodated in the gap between the large NM microgels even in moderately concentrated state. This characteristic packing substantially masks the contribution of the small N microgels at low φN, explaining the φN-independent G0 and γc as well as the first yielding governed solely by the large NM microgels. The second yielding results from the emerged contribution of the small N microgels expelled out from the gap by the positional rearrangements after the first yielding. The binary homo-N/N pastes with the similarly large size disparity at low φsmall also exhibit the φsmall-independent values of G0, but they show one-step yielding, indicating that the two-step yielding requires not only sufficiently large size disparity but also chemical dissimilarity (different values of γc) between the two components.
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Affiliation(s)
- Saori Minami
- Department of Macromolecular Science and Engineering, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585, Japan.
| | - Takumi Watanabe
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan.
| | - Yuma Sasaki
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan.
| | - Haruka Minato
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan.
| | - Atsushi Yamamoto
- Department of Macromolecular Science and Engineering, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585, Japan.
| | - Daisuke Suzuki
- Graduate School of Textile Science & Technology, Shinshu University, Ueda 386-8567, Japan. and Research Initiative for Supra-Materials, Interdisciplinary Cluster for Cutting Edge Research, Shinshu University, Ueda 386-8567, Japan
| | - Kenji Urayama
- Department of Macromolecular Science and Engineering, Kyoto Institute of Technology, Sakyo-ku, Kyoto 606-8585, Japan.
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20
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Minami S, Yamamoto A, Oura S, Watanabe T, Suzuki D, Urayama K. Criteria for colloidal gelation of thermo-sensitive poly(N-isopropylacrylamide) based microgels. J Colloid Interface Sci 2020; 568:165-175. [DOI: 10.1016/j.jcis.2020.02.047] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/12/2020] [Accepted: 02/13/2020] [Indexed: 11/24/2022]
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21
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Bergman MJ, Pedersen JS, Schurtenberger P, Boon N. Controlling the morphology of microgels by ionic stimuli. SOFT MATTER 2020; 16:2786-2794. [PMID: 32104825 DOI: 10.1039/c9sm02170a] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Stimuli-responsive microgels have attracted much interest for their use as vehicles for drug delivery or as the building blocks of adaptive materials. Ionic microgel particles, including popular poly(NIPAM-co-acrylic acid), show strong mechanical responsiveness to many external stimuli, including changes in ionic strength or acidity. In this work, we demonstrate that combining multiple ionic stimuli can enable detailed control over the morphology of microgels. To this extent, we analyze the particle morphology in various surroundings with light-scattering techniques. First, we find strong indications of an inverted density profile in the core of the particles. Secondly, we show that the swelling of this hydrogel core and the corona of dangling polymer ends can be targeted separately by a combination of deionization and deprotonation steps. Hence, this work represents an advance in tailoring particle morphologies after synthesis in a predictable fashion.
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Affiliation(s)
- Maxime J Bergman
- Division of Physical Chemistry, Lund University, SE-22100 Lund, Sweden.
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22
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Immink JN, Maris JJE, Schurtenberger P, Stenhammar J. Using Patchy Particles to Prevent Local Rearrangements in Models of Non-equilibrium Colloidal Gels. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:419-425. [PMID: 31763852 PMCID: PMC6994064 DOI: 10.1021/acs.langmuir.9b02675] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 10/30/2019] [Indexed: 06/10/2023]
Abstract
Simple models based on isotropic interparticle attractions often fail to capture experimentally observed structures of colloidal gels formed through spinodal decomposition and subsequent arrest: the resulting gels are typically denser and less branched than their experimental counterparts. Here, we simulate gels formed from soft particles with directional attractions ("patchy particles"), designed to inhibit lateral particle rearrangement after aggregation. We directly compare simulated structures with experimental colloidal gels made using soft attractive microgel particles, by employing a "skeletonization" method that reconstructs the three-dimensional backbone from experiment or simulation. We show that including directional attractions with sufficient valency leads to strongly branched structures compared to isotropic models. Furthermore, combining isotropic and directional attractions provides additional control over aggregation kinetics and gel structure. Our results show that the inhibition of lateral particle rearrangements strongly affects the gel topology and is an important effect to consider in computational models of colloidal gels.
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Affiliation(s)
- Jasper N. Immink
- Division
of Physical Chemistry, Lund University, 22100 Lund, Sweden
| | - J. J. Erik Maris
- Inorganic
Chemistry and Catalysis Group, Utrecht University, 3584 CG Utrecht, The Netherlands
| | - Peter Schurtenberger
- Division
of Physical Chemistry, Lund University, 22100 Lund, Sweden
- Lund
Institute of advanced Neutron and X-ray Science (LINXS), Lund University, 22100 Lund, Sweden
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23
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Facile formation of salecan/agarose hydrogels with tunable structural properties for cell culture. Carbohydr Polym 2019; 224:115208. [DOI: 10.1016/j.carbpol.2019.115208] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 08/12/2019] [Accepted: 08/15/2019] [Indexed: 12/25/2022]
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24
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Fussell SL, Bayliss K, Coops C, Matthews L, Li W, Briscoe WH, Faers MA, Royall CP, van Duijneveldt JS. Reversible temperature-controlled gelation in mixtures of pNIPAM microgels and non-ionic polymer surfactant. SOFT MATTER 2019; 15:8578-8588. [PMID: 31642834 DOI: 10.1039/c9sm01299k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We investigate the reversible gelation of poly(N-isopropylacrylamide) (pNIPAM) microgels in the presence of triblock-copolymer (PEO-PPO-PEO type) surfactant. We demonstrate that the association of these polymers with the microgel particles at elevated temperature is responsible for the gelation, due to the temperature responsive nature of the components. This is highlighted by an increase in the apparent hydrodynamic diameter of the particles in dynamic light scattering experiments, which only occurs above the volume phase transition temperature of pNIPAM. The gels that result shrink over a time period much larger than that of the collapse of pNIPAM microgels, and retain the shape of the container they form in. We investigate the mechanism that leads to this gelation and the structure of the gels that result. Confocal microscopy experiments show that both polymers are present in the gel network, indicating that an associative mechanism is responsible for the gelation. We vary the pNIPAM particle architecture to further investigate the gelation process, and find that the cross-link distribution plays a key role in the gelation mechanism, where for uniformly cross-linked particles the gelation is not observed. This shows that the fuzzy corona of the pNIPAM microgels is involved in the association of the polymers, allowing the triblock-copolymer to penetrate the outer corona of the microgels and bridge the particles. The phase transition observed is close to physiological conditions, so these gels have the potential for use in biomedical applications, including tissue engineering.
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Affiliation(s)
- S L Fussell
- School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
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25
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Peng F, Månsson LK, Holm SH, Ghosh S, Carlström G, Crassous JJ, Schurtenberger P, Tegenfeldt JO. A Droplet-Based Microfluidics Route to Temperature-Responsive Colloidal Molecules. J Phys Chem B 2019; 123:9260-9271. [PMID: 31584820 DOI: 10.1021/acs.jpcb.9b07754] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Small clusters of spherical colloids that mimic real molecules, so-called colloidal molecules, hold great promise as building blocks in bottom-up routes to new materials. However, their typical hard sphere nature has hampered their assembly into ordered structures, largely due to a lack of control in the interparticle interactions. To provide easy external control of the interactions, the present work focuses on the preparation of colloidal molecules from temperature-responsive microgel particles that undergo a transition from a soft repulsive to a short-range attractive state as their characteristic volume phase transition temperature (VPTT) is crossed. Preparation of the colloidal molecules starts with the use of a droplet-based microfluidics device to form highly uniform water-in-oil (W/O) emulsion droplets containing, on average and with a narrow distribution, four microgels per droplet. Evaporation of the water then leads to the formation of colloidal molecule-like clusters, which can be harvested following cross-linking and phase transfer. We use a mixture of two types of microgels, one based on poly(N-isopropylacrylamide) (PNIPAM) and the other on poly(N-isopropylmethacrylamide) (PNIPMAM), to prepare bicomponent colloidal molecules, and show that the difference in VPTT between the two allows for induction of attractive interparticle interactions between the PNIPAM interaction sites at temperatures in between the two VPTTs, analogous to the interactions among patchy biomacromolecules such as many proteins.
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Affiliation(s)
| | | | | | | | | | | | - Peter Schurtenberger
- NanoLund , SE-22100 Lund , Sweden.,Lund Institute of advanced Neutron and X-ray Science (LINXS) , Lund University , SE-22370 Lund , Sweden
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