Fabrication and Characterization of Electrospun PCL/GelMA Composite Scaffolds for Muscle Tissue Engineering

Muscle tissue engineering seeks to develop biomimetic scaffolds capable of restoring or replacing damaged muscle by promoting cell alignment, proliferation, and differentiation within a controlled microenvironment. This study presents a novel hybrid scaffold combining electrospun polycaprolactone (PCL) fibers with gelatin methacryloly (GelMA) hydrogel. The scaffold integrates the topographical guidance of aligned PCL fibers with the supportive 3D matrix of GelMA to promote muscle tissue formation.

Electrospun PCL fibers (random/aligned) were incorporated into GelMA hydrogel to form a composite scaffold. Fiber morphology and orientation were analyzed using scanning electron microscopy (SEM), and surface modification of PCL fibers following plasma treatment was confirmed via Fourier transform infrared (FTIR) spectroscopy. Mechanical properties were assessed through tensile testing, and viscoelastic behavior was evaluated via rheometry. Cell viability and proliferation were assessed using live/dead and metabolic assays. Myogenic differentiation was evaluated by immunofluorescence staining of myosin heavy chain 2 (MYH2), and myotube formation was quantified by fusion index.

Aligned PCL fibers significantly enhanced scaffold mechanics, with tensile strength and Young's modulus increasing five- and six-fold, respectively, compared to randomly oriented fibers. The fiber-reinforced GelMA scaffold showed a 45-fold increase in storage modulus (G') relative to GelMA alone. Enhanced cell viability and proliferation were observed. F-actin staining confirmed cell alignment along the fiber axis. MYH2 expression indicated improved myogenic differentiation, with the highest fusion index reaching 34.3%.

The PCL/GelMA hybrid scaffold exhibits excellent mechanical and biological performance, highlighting its potential for skeletal muscle tissue regeneration.