Shear viscoelasticity of electrospinning PCL nanofibers reinforced alginate hydrogels

Abstract

Articular cartilage has limited self-repair capacity due to the lack of vascularization, innervation and lymphatic networks. Biomimetic scaffolds with features of the extracellular matrix (ECM) of cartilage are advantageous to repair the injured cartilage tissue, but it remains a challenge to regulate its shear viscoelasticity to meet the needs of applications as articular cartilages. Fiber reinforced hydrogel is of great significance for their clinical application as cartilage tissue engineering scaffolds, especially for repairing the fibrocartilage tissue like meniscus or temporomandibular joint disc. In order to promote the shear viscoelasticity of alginate hydrogels, which was seldom studied, electrospinning PCL nanofiber layers were added into the alginate hydrogels to prepare PCL nanofibers reinforced alginate hydrogel composites (PNRAHCs). Compared with neat alginate hydrogel scaffolds, the PNRAHCs presented coral-like structure and spider web-like structure, and some PCL nanofibers form reinforced fiber bundles. Those special structures make the PNRAHCs have higher porosity, higher shear storage modulus and higher shear loss modulus than the neat alginate hydrogels, indicating better shear mechanical properties. They have the potential to be applied as the scaffolds to repair fibrocartilage tissues.