On the viscoelastic properties of alginate/nHA composite hydrogels for potential bone tissue engineering
Date
2023-09-05
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
0000-0003-3960-9801
Type
Thesis
Degree Level
Masters
Abstract
Viscoelastic properties of biomaterials in tissue engineering have been recognized recently
important. In bone tissue engineering, alginate/nano-hydroxyapatite (nHA) composite materials
have been drawn considerable attention; however, their viscoelastic properties have not been well
discovered and documented in the literature. As inspired, this thesis is to perform an experimental
study on the viscoelastic properties of alginate/nHA composite hydrogels with the focus on
identifying the effect of nHA reinforcement under varying concentrations of calcium chloride
dihydrate (CaCl2) crosslinking solution.
In this study, 12 sets or groups of composite hydrogel samples were designed and prepared by
changing the percentage of nHA from 0 to 6 (with an increment of 2% w/v) and using three
different crosslinking CaCl2 concentrations (50, 75 and 100 mM). The viscoelastic properties of
alginate/nHA composite hydrogel was examined with the help of sinusoidal cyclic compression
test conducted at the physiological frequency of 1 Hz. The viscoelastic properties of composite
hydrogels were determined in terms of loss, storage and complex moduli along with the loss
tangent, percentages of energy released and hysteresis loss.
The results from this study demonstrated that the viscoelastic properties in the case of 100 mM
CaCl2 concentration increased with nHA, and that the loss tangent values increased nHA and
reached a maximal value the case of 75 mM CaCl2 concentration, whereas, with increasing
concentration of CaCl2, 4% nHA composite showed the maximal loss tangent value. The combined
effect of % nHA and CaCl2 concentration on different viscoelastic properties was also examined
with the help of multilinear regression analysis. It has been observed through multilinear
regression that the viscoelastic properties of composite hydrogel can be improved by increasing
the nHA. The effect of crosslinking concentration on moduli values was found to be negative,
whereas, the effect of CaCl2 on loss tangent and hysteresis loss was observed to be insignificant.
Combined together, this study has demonstrated that the viscoelastic properties of composite
alginate/nHA hydrogels could be significantly affected by the concentration of nHA and
crosslinking solution. The composite hydrogels examined in this study show promise or potential
in bone tissue engineering scaffolds, particularly to mimic the bone viscoelastic properties.
Description
Keywords
Tissue engineering, Viscoelasticity, Alginate, Nano-hydroxyapatite, Bone tissue engineering, Scaffolds, Crosslinking, composite
Citation
Degree
Master of Science (M.Sc.)
Department
Mechanical Engineering
Program
Mechanical Engineering