Composite Alginate Dialdehyde-Gelatin (ADA-GEL) Hydrogel Containing Short Ribbon-Shaped Fillers for Skeletal Muscle...

Area of Science:

• Biomaterials Science
• Tissue Engineering
• Regenerative Medicine

Background:

• Skeletal muscle damage often exceeds self-repair capabilities, requiring advanced biofabrication and tissue engineering solutions.
• Developing anisotropic structures with enhanced cell alignment is crucial for effective skeletal muscle tissue reconstruction.

Purpose of the Study:

• To create a composite bioink from oxidized alginate (ADA) and gelatin (GEL) with cell-laden fillers for skeletal muscle tissue engineering.
• To optimize plasma treatment and protein coating for poly(lactic-co-glycolic acid) (PLGA) ribbon surfaces to improve cell adhesion.
• To determine the optimal calcium chloride (CaCl2) concentration for cross-linking ADA-GEL hydrogels, evaluating physical, mechanical, and cellular properties.

Main Methods:

• Fabrication of a composite bioink using oxidized alginate (ADA) and gelatin (GEL) with ribbon-shaped fillers.
• Evaluation of different plasma treatments and fibronectin coating on PLGA ribbon surfaces for cell adhesion.
• Investigation of various CaCl2 concentrations for ionic cross-linking of ADA-GEL hydrogels.
• Assessment of hydrogel properties including pore size, degradation, mechanical strength, cell viability, and proliferation.

Main Results:

• Oxygen plasma activation (30 W, 5 min) followed by fibronectin coating significantly enhanced cell adhesion and differentiation on PLGA ribbons.
• The optimal cross-linking concentration for the ADA-GEL formulation (2.5%w/v ADA, 3.75%w/v GEL) was determined to be 60 mM CaCl2.
• The optimized hydrogels exhibited a compression modulus similar to native muscle tissue (11.5 kPa), high C2C12 cell viability (>80%), and robust proliferation over 7 days.
• Rheological analysis confirmed the composite bioink's suitability, demonstrating shear-thinning and favorable flow behavior.

Conclusions:

• A composite bioink of oxidized alginate and gelatin with functionalized fillers shows significant promise for skeletal muscle tissue engineering.
• Optimized surface treatment and cross-linking strategies are critical for enhancing cell integration and mechanical properties of engineered muscle constructs.
• This bioink formulation supports high cell viability and proliferation, offering a viable platform for future muscle regenerative therapies.