Soft-Tissue-Mimicking Using Hydrogels for the Development of Phantoms

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Biophysics

Background:

• Accurately replicating the mechanical properties of soft biological tissues remains a significant challenge due to material limitations and insufficient data.
• Tissue phantoms offer a viable approach for simulating biological tissues, advancing research and development in medical applications.

Purpose of the Study:

• To investigate and characterize the mechanical properties of various soft organs (liver, heart, kidney, brain).
• To evaluate a range of hydrogel materials (agarose, polyvinyl alcohol -PVA-, Phytagel -PHY-, methacrylate gelatine -GelMA-) as potential tissue mimics.
• To establish correlations between organ mechanical properties and hydrogel characteristics for optimal phantom development.

Main Methods:

• Mechanical property testing including viscoelastic behavior, hardness, and non-linear elastic response.
• Systematic evaluation of diverse hydrogel formulations and concentrations.
• Comparative analysis of tested hydrogels against measured organ mechanical data.

Main Results:

• Significant variations in mechanical properties were observed among the tested soft tissues, exhibiting differences in elasticity, viscosity, hardness, and softness.
• Specific hydrogel concentrations demonstrated suitability for mimicking particular organs: 1% agarose for liver, 2% agarose for heart, and 4% GelMA for kidney and brain.
• Polyvinyl alcohol (PVA) and Phytagel (PHY) were found unsuitable for mimicking any of the studied organs.

Conclusions:

• 1% wt agarose is optimal for mimicking liver mechanical properties.
• 2% wt agarose is optimal for mimicking heart mechanical properties.
• 4% wt GelMA is optimal for mimicking kidney and brain mechanical properties, alongside 1% wt agarose for the brain.