Surface-Localized Crosslinked MEW PCL-Hydrogel Scaffolds with Tunable Porosity for Enhanced Cell Adhesion and...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Polymer Chemistry

Background:

• Hydrogels are vital for tissue engineering scaffolds due to biocompatibility but have poor mechanical strength.
• Fiber-reinforced composites improve mechanical properties, yet nonporous designs impede cell infiltration and nutrient transport.
• Existing methods often fill interfiber pores, limiting oxygen and nutrient diffusion crucial for cell colonization.

Purpose of the Study:

• To create porous composite scaffolds by surface-grafting sodium alginate hydrogel onto melt electrowritten fibers.
• To investigate the impact of controlled hydrogel grafting and pore size on scaffold properties and cell behavior.
• To optimize scaffold design for enhanced tissue engineering applications by maintaining structural porosity.

Main Methods:

• Fabrication of porous scaffolds using melt electrowriting and surface grafting of sodium alginate (SA) hydrogel.
• Controlled hydrogel grafting by adjusting SA concentration and SA:CaCl2 crosslinking ratio.
• Evaluation of scaffold properties including swelling, degradation, mechanical strength, and biocompatibility.
• Assessment of cell adhesion, viability, invasion, and colonization within the porous scaffolds.

Main Results:

• Porous composite scaffolds exhibited enhanced swelling capacity, degradation ratio, and mechanical properties compared to nonporous counterparts.
• Optimal cell adhesion and viability were achieved at 0.5% SA concentration and a 2:1 SA:CaCl2 crosslinking ratio.
• Preserving the porous structure facilitated superior oxygen and nutrient exchange, promoting cell infiltration and colonization.
• The surface-grafting method allowed precise control over hydrogel amount and pore size.

Conclusions:

• Surface-grafting hydrogel onto fibers while preserving scaffold porosity is a viable strategy to overcome limitations of traditional composite scaffolds.
• The developed porous composite scaffolds demonstrate significant potential for tissue engineering applications due to improved mechanical properties and cell interactivity.
• Maintaining interfiber porosity is critical for effective nutrient/oxygen transport and cell integration in tissue engineering scaffolds.