Preclinical evaluation of skin substitutes

Area of Science:

• Biomaterials Science
• Wound Healing Research
• Tissue Engineering

Background:

• Synthetic skin substitutes are crucial for wound management, requiring specific properties for effective clinical application.
• Standardized preclinical assessment procedures are essential to ensure the safety and efficacy of these advanced wound care materials.

Purpose of the Study:

• To establish and validate preclinical assessment procedures for synthetic skin substitutes.
• To evaluate critical parameters including water vapor permeability, adherence, oxygen permeability, mechanical strength, microbial barrier function, and exudate absorption capacity.

Main Methods:

• Water vapor permeability assessed using in vitro ('Water Cup', 'Inverted Cup') and in vivo ('Ventilated Hygrometer Chamber', Evaporimeter) techniques.
• Adherence evaluated via pulling and peeling force measurements on rat excised wound models.
• Oxygen permeability measured using a custom-fabricated electrochemical cell.
• Microbial barrier function tested using an in vitro model simulating colonized wounds.
• Exudate absorption capacity determined by weight gain after soaking in various biological fluids.

Main Results:

• The Evaporimeter provided accurate and simple measurements of water vapor permeability.
• Adherence forces were found to be dependent on the skin substitute's composition.
• Developed methods demonstrated the microbial impermeability of tested synthetic skin substitutes (Bioclusive, Geliperm).
• Exudate absorption varied based on the material's composition and nature.

Conclusions:

• The established preclinical assessment procedures provide a comprehensive framework for evaluating synthetic skin substitutes.
• These validated methods are suitable for assessing novel skin substitute formulations, including hydrogel-based materials.
• The study highlights the importance of material composition in determining the performance characteristics of skin substitutes.