Fabrication and Characterization of Polylactic Acid/Hyaluronic Acid/Collagen Nanofibers for Tendon Tissue Engineering

Tendons are highly elastic connective tissues that transfer mechanical loads from muscle to bone, and their healing is often slow and incomplete because of limited vascularization. Tissue engineering approaches are therefore emerging as promising alternatives to support tendon repair. In this study, polylactic acid (PLA)-based nanofibers containing hyaluronic acid (HA) and collagen (COL), intrinsic components of the extracellular matrix, were fabricated by blend and coaxial electrospinning. Matrices of identical overall composition were produced by both configurations, so that the contribution of nanofiber architecture could be isolated from that of chemical composition; the coaxial nanofibers comprised a load-bearing PLA/COL core and a PLA/HA shell, reproducing the collagen-rich tendon proper and the hyaluronic acid-rich gliding surface of native tendon. Mean fiber diameters ranged from 319 ± 82 nm for neat PLA to 854 ± 220 nm for the coaxial nanofibers, approximately twice that of the compositionally identical blend nanofibers (454 ± 110 nm). Tensile strength increased from 2.108 MPa for neat PLA to 4.94 MPa for PLA/COL, and the coaxial nanofibers retained a comparable value (4.651 MPa, p > 0.05) despite the incorporation of HA. In human mesenchymal stem cells, viability was maintained or increased over 7 days on the coaxial scaffolds but declined markedly on the blend scaffolds, indicating that the core-shell architecture is more favorable for tendon tissue regeneration.