Effect of Electrospun Fiber Mat Thickness and Support Method on Cell Morphology

Area of Science:

• Biomaterials Science
• Cellular Mechanobiology
• Tissue Engineering

Background:

• Electrospun fiber mats (EFMs) are versatile biomaterials with tunable properties like pore size and fiber diameter.
• Scaffold mechanical properties, particularly thickness and support effects, are under-characterized in EFM research.
• Existing studies often rely solely on Young's modulus, neglecting other critical mechanical variables.

Purpose of the Study:

• To investigate the influence of EFM thickness and support methodologies on cell-mechanical response.
• To enhance the understanding of scaffold mechanical properties in EFM design.
• To explore how EFM features beyond Young's modulus affect cellular behavior.

Main Methods:

• Designed polycaprolactone EFMs with varying thicknesses (50-200 µm).
• Utilized different supporting methodologies: direct electrospinning onto supports, suspension across annular gaps (3 or 10 mm), and tension-released suspension.
• Quantified single cell spreading (Feret diameter) in response to varied EFM features.

Main Results:

• Cell spreading was sensitive to EFM thickness and suspended gap diameter.
• Greatest cell spreading occurred with 50 µm EFMs over a 3 mm gap, contrary to typical mechanobiology expectations.
• Cells detected underlying rigid supports (polystyrene, PDMS), indicating substrate influence on EFM mechanics.
• EFM curvature and internal tension may influence cell response independently of Young's modulus.

Conclusions:

• EFM thickness and support configuration are critical, often overlooked, parameters influencing cell behavior.
• Findings suggest that thinner EFMs and smaller suspended gaps promote greater cell spreading.
• These insights can guide improved EFM scaffold design for enhanced performance in biomedical applications.
• Consideration of EFM curvature and support interactions is crucial for optimizing scaffold-cell interactions and patient outcomes.