Development and mechanical characterisation of self-compressed collagen gels

C.E. Andriakopoulou, A.A. Zadpoor, M.H. Grant, P.E. Riches

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Collagen gels are considered a promising biomaterial for the manufacturing of tissue engineering scaffolds, however, their mechanical properties often need to be improved to enable them to provide enough mechanical support during the course of tissue regeneration process. In this paper, we present a simple self-compression technique for the improvement of the mechanical properties of collagen gels, identified by the fitting of bespoke biphasic finite element models. Radially-confined highly hydrated gels were allowed to self-compress for 18 hours, expelling fluid, and which were subsequently subjected to unconfined ramp-hold compression. Gels, initially of 0.2%, 0.3% and 0.4% (w/v) collagen and 13mm thickness, transformed to 2.9 ± 0.2%, 3.2 ± 0.3% and 3.6 ± 0.1% (w/w) collagen and 0.45 ± 0.06 mm, 0.69 ± 0.04 mm and 0.99 ± 0.07 mm thickness. Young's moduli of the compressed gels did not increase with increasing collagen fibril density, whilst zero-strain hydraulic permeability significantly decreased from 51 to 21 mm4/Ns. The work demonstrates that biphasic theory, applied to unconfined compression, is a highly appropriate paradigm to mechanically characterise concentrated collagen gels and that confined compression of highly hydrated gels should be further investigated to enhance gel mechanical performance.
LanguageEnglish
Number of pages17
JournalMaterials Science and Engineering: C
Early online date28 Nov 2017
DOIs
Publication statusE-pub ahead of print - 28 Nov 2017

Fingerprint

collagens
Collagen
Gels
gels
mechanical properties
Tissue Scaffolds
Tissue regeneration
Mechanical properties
tissue engineering
Biocompatible Materials
Scaffolds (biology)
ramps
regeneration
Tissue engineering
Biomaterials
hydraulics
modulus of elasticity
permeability
manufacturing
Elastic moduli

Keywords

  • collagen gels
  • hydraulic permeability
  • biphasic theory

Cite this

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title = "Development and mechanical characterisation of self-compressed collagen gels",
abstract = "Collagen gels are considered a promising biomaterial for the manufacturing of tissue engineering scaffolds, however, their mechanical properties often need to be improved to enable them to provide enough mechanical support during the course of tissue regeneration process. In this paper, we present a simple self-compression technique for the improvement of the mechanical properties of collagen gels, identified by the fitting of bespoke biphasic finite element models. Radially-confined highly hydrated gels were allowed to self-compress for 18 hours, expelling fluid, and which were subsequently subjected to unconfined ramp-hold compression. Gels, initially of 0.2{\%}, 0.3{\%} and 0.4{\%} (w/v) collagen and 13mm thickness, transformed to 2.9 ± 0.2{\%}, 3.2 ± 0.3{\%} and 3.6 ± 0.1{\%} (w/w) collagen and 0.45 ± 0.06 mm, 0.69 ± 0.04 mm and 0.99 ± 0.07 mm thickness. Young's moduli of the compressed gels did not increase with increasing collagen fibril density, whilst zero-strain hydraulic permeability significantly decreased from 51 to 21 mm4/Ns. The work demonstrates that biphasic theory, applied to unconfined compression, is a highly appropriate paradigm to mechanically characterise concentrated collagen gels and that confined compression of highly hydrated gels should be further investigated to enhance gel mechanical performance.",
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Development and mechanical characterisation of self-compressed collagen gels. / Andriakopoulou, C.E.; Zadpoor, A.A.; Grant, M.H.; Riches, P.E.

In: Materials Science and Engineering: C , 28.11.2017.

Research output: Contribution to journalArticle

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