A hyaluronic acid/PVA electrospun coating on 3D printed PLA scaffold for orthopedic application

Abstract
The need for bone tissue replacement, repair and regeneration for orthopedic application is constantly growing. Therefore, the application of cartilage substitute due to the lack of donors as well as biocompatibility leads to immune system rejection. In order to overcome these drawbacks, researchers have used porous scaffold as an option for bone transplantation. In this study, poly-lactic acid (PLA) scaffolds were prepared for cartilage application by fused deposition modeling (FDM) technique and then coated by electrospinning with polyvinyl alcohol (PVA) and hyaluronic acid (HLA) fibers. Hybrid electrospinning (ELS) method was used to produce porous scaffolds from HLA–PVA polymers. The printed scaffold was coated using FDM technique and the mechanical and biological investigation was performed on the polymeric composite specimen. The functional group and morphological behavior were investigated using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques. The obtained porous scaffold has hydrophilic properties as the PVA and HLA were coated on the PLA. The porous 3D-printed scaffold containing PLA/PVA/HLA scaffold does not show any toxicity in MTT evaluation after 1, 3 and 7 days. The SEM image confirmed the cell adhesion of the chondrite to the scaffold. Also, the mechanical performances of the sample, such as elastic modulus and compressive strength, were evaluated by compression test. By electro-spun coating, the elastic module of PVA/PLA and PLA/PVA/HLA scaffolds has increased to 18.31 ± 0.29 MPa and 19.25 ± 0.38 MPa. Also, the tensile strength of these two porous scaffolds has reached 6.11 ± 0.42 MPa and 6.56 ± 0.14 MPa, respectively. The failure strain of 3D printed PLA scaffold was reported to be 53 ± 0.21% and this value was reduced to 47 ± 0.62% and 42 ± 0.22% in PVA/PLA and PLA/PVA/HLA scaffolds. The cells’ growth on the porous scaffolds showed a broad, spindle-shaped and regular shape. The obtained results of the chemical, physical and biological analyses showed that porous PLA/PVA/HLA scaffold has potential applications in cartilage construction.