Nitrogen Plasma-Modified Silk Fibroin Films Promote Wettability and Airway Epithelial Cell Growth

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Surface Chemistry

Background:

• Surface properties critically regulate cell behavior in bioengineered tissue scaffolds.
• Understanding surface wettability's impact on airway epithelial cells is vital for functional airway graft development.

Purpose of the Study:

• To investigate the effect of nitrogen low-temperature plasma (N2 LTP) on silk fibroin film wettability and primary human bronchial epithelial cell (HBEC) growth.
• To establish a correlation between surface wettability and HBEC adhesion and proliferation.

Main Methods:

• 3D printing of silk fibroin films (opaque and transparent).
• Nitrogen low-temperature plasma (N2 LTP) treatment to modify surface wettability.
• Characterization of surface wettability via water contact angle (WCA) measurements.
• Assessment of HBEC growth, density, and morphology over 28 days.
• Surface property analysis using Fourier transform infrared and Raman spectroscopies.

Main Results:

• N2 LTP treatment significantly reduced WCA from ~60° to ~30°, enhancing surface wettability.
• N2 LTP treatment increased HBEC density and decreased cell contour area, promoting monolayer formation.
• Surface modification by N2 LTP was independent of bulk silk fibroin properties.
• Both 3D printing and N2 LTP were performed at room temperature, indicating a mild processing approach.

Conclusions:

• Enhanced surface wettability of silk fibroin films via N2 LTP treatment promotes HBEC growth.
• Surface wettability plays a crucial role in mediating epithelial cell adhesion and proliferation.
• This study provides insights into nitrogen plasma modification of silk fibroin for airway graft development.