Alginate Hydrogels as Biomaterials

Augst, Alexander; Kong, Hyun Joon; Mooney, David J.

doi:10.1002/mabi.200600069

Cited by 1,581 publications

(1,152 citation statements)

References 103 publications

Supporting

Mentioning

1,123

Contrasting

Unclassified

Order By: Relevance

“…Alginate is a polysaccharide isolated from brown algae which has been used with great success as a wound dressing (Augst et al 2006) and as a food additive. On dissolution in an aqueous medium, alginate forms a hydrocolloid, which gels ionotropically following the addition of multivalent cations.…”

Section: Alginatementioning

confidence: 99%

Cell encapsulation using biopolymer gels for regenerative medicine

2010

View full text Add to dashboard Cite

To cite this version:Nicola C. Hunt, Liam M. Grover. Cell encapsulation using biopolymer gels for regenerative medicine. Biotechnology Letters, Springer Verlag, 2010, 32 (6), pp.733-742. <10.1007/s10529-010-0221-0>. Abstract There has been a consistent increase in the mean life expectancy of the population of the developed world over the past century. Healthy life expectancy, however, has not increased concurrently. As a result we are living a larger proportion of our lives in poor health and there is a growing demand for the replacement of diseased and damaged tissues. While traditionally tissue grafts have functioned well for this purpose, the demand for tissue grafts now exceeds the supply. For this reason, research in regenerative medicine is rapidly expanding to cope with this new demand. There is now a trend towards supplying cells with a material in order to expedite the tissue healing process. Hydrogel encapsulation provides cells with a three dimensional environment similar to that experienced in vivo and therefore may allow the maintenance of normal cellular function in order to produce tissues similar to those found in the body. In this review we discuss biopolymeric gels that have been used for the encapsulation of mammalian cells for tissue engineering applications as well as a brief overview of cell encapsulation for therapeutic protein production. This review focuses on agarose, alginate, collagen, fibrin, hyaluronic acid and gelatin since they are widely used for cell encapsulation. The literature on the regeneration of cartilage, bone, ligament, tendon, skin, blood vessels and neural tissues using these materials has been summarised.

show abstract

Section: Alginatementioning

confidence: 99%

Cell encapsulation using biopolymer gels for regenerative medicine

2010

View full text Add to dashboard Cite

show abstract

“…For example, fibrin properties can be varied by adjusting the concentration of fibrinogen and thrombin [68], and Martens et al adjusted these parameters to optimize fibrin viscosity and gelation for catheter delivery [69]. Similarly, alginate properties can be adjusted by varying the weight percent and the ratio of M and G units [70]. However, in both of these systems, viscosity may be changed during injection and lead to differences in not only final mechanics but also material dispersion and biomaterial concentration.…”

Section: Materials Optimization: Comparing Properties and Introducing mentioning

confidence: 99%

Injectable Acellular Hydrogels for Cardiac Repair

Tous

Purcell

Ifkovits

et al. 2011

J. of Cardiovasc. Trans. Res.

152

136

View full text Add to dashboard Cite

Injectable hydrogels are being developed as potential translatable materials to influence the cascade of events that occur after myocardial infarction. These hydrogels, consisting of both synthetic and natural materials, form through numerous chemical crosslinking and assembly mechanisms and can be used as bulking agents or for the delivery of biological molecules. Specifically, a range of materials are being applied that alter the resulting mechanical and biological signals after infarction and have shown success in reducing stresses in the myocardium and limiting the resulting adverse left ventricular (LV) remodeling. Additionally, the delivery of molecules from injectable hydrogels can influence cellular processes such as apoptosis and angiogenesis in cardiac tissue or can be used to recruit stem cells for repair. There is still considerable work to be performed to elucidate the mechanisms of these injectable hydrogels and to optimize their various properties (e.g., mechanics and degradation profiles). Furthermore, although the experimental findings completed to date in small animals are promising, future work needs to focus on the use of large animal models in clinically relevant scenarios. Interest in this therapeutic approach is high due to the potential for developing percutaneous therapies to limit LV remodeling and to prevent the onset of congestive heart failure that occurs with loss of global LV function. This review focuses on recent efforts to develop these injectable and acellular hydrogels to aid in cardiac repair.

show abstract

“…In contrast, the reloading curves in DN gels follow the previous unloading curve indicating the permanent nature of the damage occurring in these covalently crosslinked gels. The high toughness and mechanical recoverability of the hybrid gel system originates from the ionic crosslinks, where the guluronic units (also known as G group) on the alginate chains are associated by Ca 2+ ions to form a zip-like junction described by a socalled "egg-box" model [10][11][12][13]. When a hybrid gel is subject to external force the crosslinks are "unzipped", dissipating dissociation energy of the ionic bonds and entropic energy of the loaded network strands.…”

mentioning

confidence: 99%

Time-dependent mechanical properties of tough ionic-covalent hybrid hydrogels

Xin

Brown

Naficy

et al. 2015

Polymer

View full text Add to dashboard Cite

Hybrid gels featuring interpenetrating covalent and ionic crosslinked networks have recently been shown to exhibit both high toughness and recoverability of strain-induced network damage. The high toughness results from the energy dissipated as entropically strained network strands are released by the dissociation of ionic crosslinks. As in the so-called double network hydrogels, the toughening process is inherently linked to network damage. This damage, however, can be recovered to a large degree in hybrid gels due to the reformation of ionic associations when the gel is unloaded. The stability of the ionic network under load is here investigated and it is shown that these networks show large stress relaxation at constant strain, time dependent stress-strain behaviour and rate-dependent toughness. A double exponential model is invoked to mathematically describe the stress relaxation of the hybrid gels indicating at least two relaxation mechanisms. The rate-dependent toughness and the relaxation behaviour of the hybrid gels are attributed to the labile unzipping of the ionic crosslinks which is assumed to be load and time dependent. AbstractHybrid gels featuring interpenetrating covalent and ionic crosslinked networks have recently been shown to exhibit both high toughness and recoverability of strain-induced network damage. The high toughness results from the energy dissipated as entropically strained network strands are released by the dissociation of ionic crosslinks. As in the socalled double network hydrogels, the toughening process is inherently linked to network damage. This damage, however, can be recovered to a large degree in hybrid gels due to the reformation of ionic associations when the gel is unloaded. The stability of the ionic network under load is here investigated and it is shown that these networks show large stress relaxation at constant strain, time dependent stress-strain behaviour and rate-dependent toughness. A double exponential model is invoked to mathematically describe the stress relaxation of the hybrid gels indicating at least two relaxation mechanisms. The ratedependent toughness and the relaxation behaviour of the hybrid gels are attributed to the labile unzipping of the ionic crosslinks which is assumed to be load and time dependent.

show abstract

Alginate Hydrogels as Biomaterials

Cited by 1,581 publications

References 103 publications

Cell encapsulation using biopolymer gels for regenerative medicine

Cell encapsulation using biopolymer gels for regenerative medicine

Injectable Acellular Hydrogels for Cardiac Repair

Time-dependent mechanical properties of tough ionic-covalent hybrid hydrogels

Contact Info

Product

Resources

About