Fabrication and Characterization of Poly L-lactic Acid (PLLA) Nanoyarns Reinforced Nanofibrous Scaffold

摘要

The design of suitable scaffolds which could mimic the structure of natural tissue extracellular matrix (ECM) has been an important frontier of biomaterials and regenerative medical research.In this study,poly L-lactic acid (PLLA) nanoyarns bundled by nanofibers had been prepared via a modified electrospinning setup and collected by a mandrel.On the basis of it,a nanoyarns reinforced electrospun nanofibrous scaffold (NRS) had been successfully fabricated with the collection of nanoyarns and nanofibers in the meantime.The morphologies of nanoyarns and NRS were characterized by scanning electron microscopy (SEM).Tensile test and X-ray diffraction (XRD) were respectively used to investigate the mechanical property of NRS and the crystalline structure of nanoyarns and nanofibers.SEM images revealed that the uniform nanoyarns bundled by aligned nanofibers had a rough surface and distributed uniformLy within the scaffolds.Moreover,the NRS could keep high surface-to-volume ratio and interconnected porous architecture similar to electrospun nanofibrous scaffold (ENS) and own distinct nano-and micro-structures,which could match the scale of natural extracellular matrix (ECM) nicely.XRD analysis showed that the crystalline structure of PLLA molecule had transformed in the process of fabrication.The result of tensile tests illustrated that the embeded nanoyarns could significantly improve the tensile strength in the direction parallel to the nanoyams of NRS,which made a great potential on tendon,ligament and vessel regeneration.