Characterization of mouse artery tissue properties using experimental testing combined with finite element modelling

Area of Science:

• Biomechanics and Biomaterials Science
• Computational Mechanics
• Tissue Engineering and Regenerative Medicine

Background:

• Indentation testing is crucial for determining arterial tissue mechanical properties.
• Extracting accurate material parameters from force-indentation data remains challenging, especially with rough biological surfaces.

Purpose of the Study:

• To develop and validate a method for determining first-order Ogden parameters (μ and α) for mouse arterial tissue.
• To address the complication of specimen surface roughness in indentation analysis.

Main Methods:

• Combined indentation tests with numerical simulations, building on prior work (Li and Masen, 2024).
• Introduced an 'equivalent thickness' concept to manage specimen surface irregularity in Hayes' model.
• Linearized hyperelastic behavior for small strain increments (≤ 1%) and applied Hooke's law to derive stress-strain curves.

Main Results:

• Successfully recovered input Ogden parameters and thickness from simulated data.
• Applied to 26 experimental curves, yielding an average shear modulus (G) of 1.22 kPa for mouse arterial tissue (range: 0.27–5.02 kPa).
• Numerical simulations confirmed the accuracy of the obtained material parameters.

Conclusions:

• The proposed method effectively determines Ogden parameters for mouse arterial tissue, even with surface roughness.
• Provides a reliable approach for characterizing the mechanical behavior of biological tissues using indentation data.
• The findings contribute to a better understanding of arterial tissue mechanics for research and clinical applications.