Quantifying the ultrastructure changes of air-dried and irradiated human amniotic membrane using atomic force...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Medical Device Sterilization

Background:

• Air-dried amnion serves as a wound dressing for burns and partial-thickness wounds.
• Standard sterilization doses (25 kGy) can alter amnion's morphological structure.
• Understanding radiation-induced ultrastructural changes is vital for optimizing amnion-based therapies.

Purpose of the Study:

• To quantify ultrastructural changes in air-dried amnion after gamma irradiation using atomic force microscopy (AFM).
• To investigate the dose-dependent effects of gamma irradiation on amnion cell dimensions and surface topography.
• To correlate AFM findings with established sterilization protocols.

Main Methods:

• Human amnion samples were processed, air-dried, and irradiated at doses of 5, 15, 25, and 35 kGy.
• Atomic force microscopy (AFM) was employed to analyze changes in epithelial cell diameter, intercellular gap size, and membrane surface roughness (Ra, Rq).
• Statistical analysis (p < 0.01) was used to determine the significance of observed changes.

Main Results:

• The longest diameter of amnion cells significantly decreased post-irradiation, independent of dose.
• Intercellular gap size significantly decreased at 15 kGy.
• Surface roughness parameters (Ra, Rq) were significantly highest at 15 kGy, indicating increased roughness.

Conclusions:

• Gamma irradiation induces quantifiable ultrastructural modifications in air-dried amnion, impacting cell dimensions and surface properties.
• AFM provides valuable data to complement other microscopy techniques for characterizing irradiated biomaterials.
• These findings aid in optimizing sterilization processes for amnion-based wound dressings.