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Jason A Burdick - One of the best experts on this subject based on the ideXlab platform.
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gallol derived ecm mimetic adhesive bioinks exhibiting temporal Shear Thinning and stabilization behavior
Acta Biomaterialia, 2019Co-Authors: Jonathan H Galarraga, Mikyung Shin, Mi Y Kwon, Haeshin Lee, Jason A BurdickAbstract:Abstract 3D bioprinting is an attractive technique to fabricate well-organized, cell-laden constructs for tissue repair and disease modeling. Although numerous hydrogel bioinks have been developed, materials are still needed that mimic the cellular microenvironment, have the appropriate viscosity and stabilization for printing, and are cytocompatible. Here, we present a unique gallol-modified extracellular matrix (ECM) hydrogel ink that is inspired by rapid fruit browning phenomena. The gallol-modification of ECM components (e.g., hyaluronic acid, gelatin) allowed (i) immediate gelation and Shear-Thinning properties by dynamic hydrogen bonds on short time-scales and (ii) further auto-oxidation and covalent crosslinking for stabilization on longer time-scales. The gallol ECM hydrogel ink was printable using an extrusion-based 3D printer by exploiting temporal Shear-Thinning properties, and further showed cytocompatibility (∼95% viability) and on-tissue printability due to adhesiveness of gallol moieties. Printed cell-laden filaments degraded and swelled with culture over 6 days, corresponding to increases in cell density and spreading. Ultimately, this strategy is useful for designing hydrogel inks with tunable properties for 3D bioprinting. Statement of Significance 3D bioprinting is a promising technique for the fabrication of cell-laden constructs for applications as in vitro models or for therapeutic applications. Despite the previous development of numerous hydrogel bioinks, there still remain challenging considerations in the design of bioinks. In this study, we present a unique cytocompatible hydrogel ink with gallol modification that is inspired by rapid fruit browning phenomena. The gallol hydrogel ink has three important properties: i) it shows immediate gelation by dynamic, reversible bonds for Shear-Thinning extrusion, ii) it allows spontaneous stabilization by subsequent covalent crosslinking after printing, and iii) it is printable on tissues by adhesive properties of gallol moieties. As such, this work presents a new approach in the design of hydrogel inks.
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rational design of network properties in guest host assembled and Shear Thinning hyaluronic acid hydrogels
Biomacromolecules, 2013Co-Authors: Christopher B Rodell, Adam L Kaminski, Jason A BurdickAbstract:Shear-Thinning hydrogels afford direct injection or catheter delivery to tissues without potential premature gel formation and delivery failure or the use of triggers such as chemical initiators or heat. However, many Shear-Thinning hydrogels require long reassembly times or exhibit rapid erosion. We developed a Shear-Thinning hyaluronic acid (HA) hydrogel based on the guest–host interactions of adamantane modified HA (guest macromer, Ad-HA) and β-cyclodextrin modified HA (host macromer, CD-HA). The ability of the guest and host molecules to interact with their counterpart following conjugation to HA was confirmed by 1H NMR spectroscopy and was similar to that of the native complex. Mixing of Ad-HA and CD-HA resulted in rapid formation of a hydrogel composed of guest–host bonds. The hydrogel physical properties, including mechanics and flow characteristics, were dependent on cross-link density and network structure, which were controlled through macromer concentration, the extent of guest macromer modific...
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rational design of network properties in guest host assembled and Shear Thinning hyaluronic acid hydrogels
Biomacromolecules, 2013Co-Authors: Christopher B Rodell, Adam L Kaminski, Jason A BurdickAbstract:Shear-Thinning hydrogels afford direct injection or catheter delivery to tissues without potential premature gel formation and delivery failure or the use of triggers such as chemical initiators or heat. However, many Shear-Thinning hydrogels require long reassembly times or exhibit rapid erosion. We developed a Shear-Thinning hyaluronic acid (HA) hydrogel based on the guest-host interactions of adamantane modified HA (guest macromer, Ad-HA) and β-cyclodextrin modified HA (host macromer, CD-HA). The ability of the guest and host molecules to interact with their counterpart following conjugation to HA was confirmed by (1)H NMR spectroscopy and was similar to that of the native complex. Mixing of Ad-HA and CD-HA resulted in rapid formation of a hydrogel composed of guest-host bonds. The hydrogel physical properties, including mechanics and flow characteristics, were dependent on cross-link density and network structure, which were controlled through macromer concentration, the extent of guest macromer modification, and the molar ratio of guest and host functional groups. The guest-host assembly mechanism permitted both Shear-Thinning behavior for ease of injection and near-instantaneous reassembly for material retention at the target sight. The hydrogel erosion and release of a model biomolecule were also dependent on design parameters and were sustained for over 60 days. These hydrogels show potential as a minimally invasive injectable hydrogel for biomedical applications.
Giovanni Radilla - One of the best experts on this subject based on the ideXlab platform.
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non darcian flow of Shear Thinning fluids through packed beads experiments and predictions using forchheimer s law and ergun s equation
Advances in Water Resources, 2017Co-Authors: Antonio Rodriguez De Castro, Giovanni RadillaAbstract:Abstract The flow of Shear-Thinning fluids through unconsolidated porous media is present in a number of important industrial applications such as soil depollution, Enhanced Oil Recovery or filtration of polymeric liquids. Therefore, predicting the pressure drop–flow rate relationship in model porous media has been the scope of major research efforts during the last decades. Although the flow of Newtonian fluids through packs of spherical particles is well understood in most cases, much less is known regarding the flow of Shear-Thinning fluids as high molecular weight polymer aqueous solutions. In particular, the experimental data for the non-Darcian flow of Shear-Thinning fluids are scarce and so are the current approaches for their prediction. Given the relevance of non-Darcian Shear-Thinning flow, the scope of this work is to perform an experimental study to systematically evaluate the effects of fluid Shear rheology on the flow rate–pressure drop relationships for the non-Darcian flow through different packs of glass spheres. To do so, xanthan gum aqueous solutions with different polymer concentrations are injected through four packs of glass spheres with uniform size under Darcian and inertial flow regimes. A total of 1560 experimental data are then compared with predictions coming from different methods based on the extension of widely used Ergun's equation and Forchheimer's law to the case of Shear Thinning fluids, determining the accuracy of these predictions. The use of a proper definition for Reynolds number and a realistic model to represent the rheology of the injected fluids results in the porous media are shown to be key aspects to successfully predict pressure drop–flow rate relationships for the inertial Shear-Thinning flow in packed beads.
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Non-Darcian flow of Shear-Thinning fluids through packed beads: Experiments and predictions using Forchheimer’s law and Ergun’s equation
Advances in Water Resources, 2017Co-Authors: Antonio Rodriguez De Castro, Giovanni RadillaAbstract:The flow of Shear-Thinning fluids through unconsolidated porous media is present in a number of impor- tant industrial applications such as soil depollution, Enhanced Oil Recovery or filtration of polymeric liq- uids. Therefore, predicting the pressure drop–flow rate relationship in model porous media has been the scope of major research efforts during the last decades. Although the flow of Newtonian fluids through packs of spherical particles is well understood in most cases, much less is known regarding the flow of Shear-Thinning fluids as high molecular weight polymer aqueous solutions. In particular, the experimen- tal data for the non-Darcian flow of Shear-Thinning fluids are scarce and so are the current approaches for their prediction. Given the relevance of non-Darcian Shear-Thinning flow, the scope of this work is to perform an experimental study to systematically evaluate the effects of fluid Shear rheology on the flow rate–pressure drop relationships for the non-Darcian flow through different packs of glass spheres. To do so, xanthan gum aqueous solutions with different polymer concentrations are injected through four packs of glass spheres with uniform size under Darcian and inertial flow regimes. A total of 1560 experimen- tal data are then compared with predictions coming from different methods based on the extension of widely used Ergun’s equation and Forchheimer’s law to the case of Shear Thinning fluids, determining the accuracy of these predictions. The use of a proper definition for Reynolds number and a realistic model to represent the rheology of the injected fluids results in the porous media are shown to be key aspects to successfully predict pressure drop–flow rate relationships for the inertial Shear-Thinning flow in packed beads.
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non darcian flow experiments of Shear Thinning fluids through rough walled rock fractures
Water Resources Research, 2016Co-Authors: Antonio Rodriguez De Castro, Giovanni RadillaAbstract:Understanding non-Darcian flow of Shear-Thinning fluids through rough-walled rock fractures is of vital importance in a number of industrial applications such as hydrogeology or petroleum engineering. Different laws are available to express the deviations from linear Darcy law due to inertial pressure losses. In particular, Darcy's law is often extended through addition of quadratic and cubic terms weighted by two inertial coefficients depending on the strength of the inertia regime. The relations between the effective Shear viscosity of the fluid and the apparent viscosity in porous media when inertial deviations are negligible were extensively studied in the past. However, only recent numerical works have investigated the superposition of both inertial and Shear-Thinning effects, finding that the same inertial coefficients obtained for non-Darcian Newtonian flow apply in the case of Shear-Thinning fluids. The objective of this work is to experimentally validate these results, extending their applicability to the case of rough-walled rock fractures. To do so, flow experiments with aqueous polymer solutions have been conducted using replicas of natural fractures, and the effects of polymer concentration, which determine the Shear rheology of the injected fluid, have been evaluated. Our findings show that the experimental pressure loss-flow rate data for inertial flow of Shear-Thinning fluids can be successfully predicted from the empirical parameters obtained during non-Darcian Newtonian flow and Darcian Shear-Thinning flow in a given porous medium. This article is protected by copyright. All rights reserved.
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Non-Darcian flow experiments of Shear-Thinning fluids through rough-walled rock fractures
Water Resources Research, 2016Co-Authors: Antonio Rodriguez De Castro, Giovanni RadillaAbstract:Understanding non-Darcian flow of Shear-Thinning fluids through rough-walled rock fractures is of vital importance in a number of industrial applications such as hydrogeology or petroleum engineering. Different laws are available to express the deviations from linear Darcy law due to inertial pressure losses. In particular, Darcy’s law is often extended through addition of quadratic and cubic terms weighted by two inertial coefficients depending on the strength of the inertia regime. The relations between the effective Shear viscosity of the fluid and the apparent viscosity in porous media when inertial deviations are negligible were extensively studied in the past. However, only recent numerical works have investigated the superposition of both inertial and Shear-Thinning effects, finding that the same inertial coefficients obtained for non-Darcian Newtonian flow applied in the case of Shear-Thinning fluids. The objective of this work is to experimentally validate these results, extending their applicability to the case of rough-walled rock fractures. To do so, flow experiments with aqueous polymer solutions have been conducted using replicas of natural fractures, and the effects of polymer concentration, which determine the Shear rheology of the injected fluid, have been evaluated. Our findings show that the experimental pressure loss-flow rate data for inertial flow of Shear-Thinning fluids can be successfully predicted from the empirical parameters obtained during non-Darcian Newtonian flow and Darcian Shear-Thinning flow in a given porous medium.
Christopher B Rodell - One of the best experts on this subject based on the ideXlab platform.
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rational design of network properties in guest host assembled and Shear Thinning hyaluronic acid hydrogels
Biomacromolecules, 2013Co-Authors: Christopher B Rodell, Adam L Kaminski, Jason A BurdickAbstract:Shear-Thinning hydrogels afford direct injection or catheter delivery to tissues without potential premature gel formation and delivery failure or the use of triggers such as chemical initiators or heat. However, many Shear-Thinning hydrogels require long reassembly times or exhibit rapid erosion. We developed a Shear-Thinning hyaluronic acid (HA) hydrogel based on the guest–host interactions of adamantane modified HA (guest macromer, Ad-HA) and β-cyclodextrin modified HA (host macromer, CD-HA). The ability of the guest and host molecules to interact with their counterpart following conjugation to HA was confirmed by 1H NMR spectroscopy and was similar to that of the native complex. Mixing of Ad-HA and CD-HA resulted in rapid formation of a hydrogel composed of guest–host bonds. The hydrogel physical properties, including mechanics and flow characteristics, were dependent on cross-link density and network structure, which were controlled through macromer concentration, the extent of guest macromer modific...
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rational design of network properties in guest host assembled and Shear Thinning hyaluronic acid hydrogels
Biomacromolecules, 2013Co-Authors: Christopher B Rodell, Adam L Kaminski, Jason A BurdickAbstract:Shear-Thinning hydrogels afford direct injection or catheter delivery to tissues without potential premature gel formation and delivery failure or the use of triggers such as chemical initiators or heat. However, many Shear-Thinning hydrogels require long reassembly times or exhibit rapid erosion. We developed a Shear-Thinning hyaluronic acid (HA) hydrogel based on the guest-host interactions of adamantane modified HA (guest macromer, Ad-HA) and β-cyclodextrin modified HA (host macromer, CD-HA). The ability of the guest and host molecules to interact with their counterpart following conjugation to HA was confirmed by (1)H NMR spectroscopy and was similar to that of the native complex. Mixing of Ad-HA and CD-HA resulted in rapid formation of a hydrogel composed of guest-host bonds. The hydrogel physical properties, including mechanics and flow characteristics, were dependent on cross-link density and network structure, which were controlled through macromer concentration, the extent of guest macromer modification, and the molar ratio of guest and host functional groups. The guest-host assembly mechanism permitted both Shear-Thinning behavior for ease of injection and near-instantaneous reassembly for material retention at the target sight. The hydrogel erosion and release of a model biomolecule were also dependent on design parameters and were sustained for over 60 days. These hydrogels show potential as a minimally invasive injectable hydrogel for biomedical applications.
Brice Lecampion - One of the best experts on this subject based on the ideXlab platform.
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A semi-infinite hydraulic fracture driven by a Shear-Thinning fluid
Journal of Fluid Mechanics, 2018Co-Authors: Fatima-ezzahra Moukhtari, Brice LecampionAbstract:We use the Carreau rheological model which properly accounts for the Shear-Thinning behaviour between the low and high Shear rate Newtonian limits to investigate the problem of a semi-infinite hydraulic fracture propagating at a constant velocity in an impermeable linearly elastic material. We show that the solution depends on four dimensionless parameters: a dimensionless toughness (function of the fracture velocity, confining stress, material and fluid parameters), a dimensionless transition Shear stress (related to both fluid and material behaviour), the fluid Shear-Thinning index and the ratio between the high and low Shear rate viscosities. We solve the complete problem numerically combining a Gauss–Chebyshev method for the discretization of the elasticity equation, the quasi-static fracture propagation condition and a finite difference scheme for the width-averaged lubrication flow. The solution exhibits a complex structure with up to four distinct asymptotic regions as one moves away from the fracture tip: a region governed by the classical linear elastic fracture mechanics behaviour near the tip, a high Shear rate viscosity asymptotic and power-law asymptotic region in the intermediate field and a low Shear rate viscosity asymptotic far away from the fracture tip. The occurrence and order of magnitude of the extent of these different viscous asymptotic regions are estimated analytically. Our results also quantify how Shear Thinning drastically reduces the size of the fluid lag compared to a Newtonian fluid. We also investigate simpler rheological models (power law, Ellis) and establish the small domain where they can properly reproduce the response obtained with the complete rheology.
Sandrine Decarre - One of the best experts on this subject based on the ideXlab platform.
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Pipe flow of a dense emulsion: homogeneous Shear-Thinning or Shear-induced migration ?
AIChE Journal, 2017Co-Authors: Micheline Abbas, Amélie Pouplin, Olivier Masbernat, Alain Liné, Sandrine DecarreAbstract:The flow field of a 70% concentrated noncolloidal o/w emulsion in a pipe has been investigated by means of Particle Image Velocimetry in a matched refractive index medium. At steady state and in laminar regime, the shape of axial velocity profiles is not parabolic and exhibits a Shear‐Thinning behavior of the dense emulsion, with a flow index of 0.5 and a negligible yield stress (less than 1 Pa). However, instead of a square root law, the pressure drop increases linearly with Um. To explain this apparent inconsistency, two mechanisms of different nature are considered. The first originates from a possible relation between the consistency factor and the drop mean diameter. The second mechanism is Shear‐induced migration and leads to the development of a concentration gradient in the pipe cross section. Both mechanisms considered reconcile the experimental data, the apparent local Shear‐Thinning behavior and the linear evolution of the pressure drop with the flow rate.
