Rheological behaviour of reconstructed skin

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Dermatology

Background:

• Reconstructed skin models are vital for tissue repair and product testing.
• Characterizing the mechanical properties of these in vitro tissues is challenging due to limitations in testing devices.
• Understanding the viscoelastic behavior is key to their functional assessment.

Purpose of the Study:

• To characterize the time-dependent mechanical behavior of reconstructed skin and its components.
• To develop and apply novel in vitro testing methods for small tissue samples.
• To model the rheological properties of reconstructed skin using established mechanical models.

Main Methods:

• Spherical indentation load-relaxation tests were performed on reconstructed skin models and sub-components (3D-scaffold, dermal equivalent).
• A specialized device was used to measure mechanical responses of small, in vitro cultured tissue samples.
• Generalized Maxwell and Kelvin-Voigt rheological models were applied to analyze the time-dependent mechanical data.

Main Results:

• The rheological behavior of reconstructed skin varied significantly based on its biological structure.
• The 3D-scaffold was best modeled by a one-branch Maxwell model.
• The dermal equivalent and the full reconstructed skin were modeled by one-branch and two-branch Kelvin-Voigt models, respectively.

Conclusions:

• Skin cells significantly influence the instantaneous mechanical relaxation of reconstructed skin.
• The 3D-scaffold plays a critical role in the long-term mechanical response and relaxation times.
• These findings provide a deeper understanding of reconstructed skin mechanics for improved tissue engineering and product validation.