![](bg6.png)
linear model and 5-parameter Maxwell-Weichert
model to describe the hydrogels’ relaxation
responses to the deformation applied by MSP. Both
models appear to show a high degree of correlation
between the actual data and the theoretical model
data (Figure 8). The values for coefficients of
determination (R²) for agarose and alginate
hydrogels were found to be greater than 0.9 using
the standard linear model and greater than 0.95 for
the Maxwell-Weichert model. This suggests that the
5-parameter Maxwell-Weichert model is capable of
providing a more accurate representation of the
relaxation response than the standard linear
model.
Figure 8: Actual and theoretical model normalised force
data for (a) a 2% alginate and (b) a 1% agarose hydrogel at
a constant indentation of 1000µm.
5 CONCLUSIONS
The MSP method has been applied to examine the
mechanical and viscoelastic characteristics of
various biomimetic materials, i.e., agarose and
alginate hydrogel membranes and their results have
been demonstrated to be satisfactory. Incorporated
with simple analyses, the new instrument has been
shown to be capable of determining quantitatively
viscoelastic and mechanical properties based on
experimental data of loading/unloading and stress
relaxation curves. The instrument has potentials for
testing other soft biological materials, such as
human and animal skins.
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