Linear viscoelastic behavior of subcutaneous adipose tissue

Area of Science:

• Biomedical Engineering
• Materials Science
• Tissue Mechanics

Background:

• Subcutaneous adipose tissue significantly influences skin's mechanical properties.
• A comprehensive constitutive model for this tissue is currently lacking.
• Understanding its mechanical behavior is crucial for developing accurate models.

Purpose of the Study:

• To measure and describe the linear viscoelastic behavior of subcutaneous adipose tissue.
• To establish a foundation for developing a constitutive model for this tissue layer.
• To assess the impact of snap freezing on tissue mechanics.

Main Methods:

• Linear viscoelastic shear experiments were conducted on porcine subcutaneous adipose tissue using a rotational rheometer.
• Measurements were performed within the linear viscoelastic regime (up to 0.1% strain).
• Time-temperature superposition and power-law modeling were applied to analyze frequency and temperature dependencies.

Main Results:

• Storage and loss moduli exhibited frequency- and temperature-dependent behavior.
• The phase angle remained independent of frequency and temperature.
• A shear modulus of 7.5 kPa at 10 rad/s and 37°C was determined.
• Time-temperature superposition was applicable.
• Snap freezing did not significantly alter mechanical properties, despite potential histological damage.

Conclusions:

• The study successfully characterized the linear viscoelastic properties of subcutaneous adipose tissue.
• The findings support the applicability of the employed methods for exploring non-linear tissue behavior.
• Snap freezing is a viable preservation method for mechanical testing of this tissue.