Study On Biocompatibility Of Polyetherimide (PEI) As Bone Repair Scaffold

Background:Bone defects caused by various reasons have seriously affected people's physical and mental health.Despite the self-healing ability of bone tissue,however,it usually cannot repair by itself when the bone defect exceeds the critical size and thus need the therapy of bone graft to promote the regeneration of the bone defect.Currently,the common used bone graft are autologous or allogeneic bone graft.However,there are some disadvantages about it such as limited bone tissue and local hematoma and chronic pain in autologous bone grafting,the risk of immune rejection and disease transmission in allogeneic bone graft.However,artificial bone substitute materials have become a hot research in bone tissue engineering research because of their good biocompatibility and osteoinductive and osteoconductive activity.Polyetherimide(PEI)is a special engineering plastics with high temperature stability,corrosion resistance,wear resistance and high mechanical strength.Besides,it has good biocompatibility and has potentially applied in hemodialysis and other biomedical fields.Moreover,the PEI is cheaper than PEEK,and it has the similar stifness to bone.However,there were fewer researches about the PEI based implant.Particularly,no study reported the biological performance of porous PEI scafold in bone tissue engineering.Therefore,in this study,we will investigate the mechanical and biological properties of PEI materials and porous PEI materials.Objective:To investigate the biocompatibility of polyetherimide and its biological behavior as a bone repair scaffold Methods:Polyetherimide porous scaffolds(P-PEIs)with pore sizes of 500-600 microns were prepared by solvent casting-particle leaching technology.The PEI and P-PEIs scaffolds were characterized by scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),water contact angle measurement and atomic force microscopy(AFM).The mechanical properties of the materials were tested by universal testing machine.The in vitro biocompatibility of P-PEIs was investigated by MC3T3-E1 cells via SEM,fuorescent staining,and CCK-8 Kit.Results:In this study,polyetherimide porous scaffolds(P-PEIs)with pore size of 500-600 um were prepared by solvent casting-particle leaching technology.According to the material characterization,P-PEIs have irregular but evenly distributed and interconnected pores,and there is no obvious change in chemical composition before and after the preparation of PPEIs porous scaffolds.The mechanical test showed that the elastic modulus of PEI material was close to that of normal cortical bone,and the elastic modulus of P-PEIs porous scaffold was close to that of normal cancellous bone.In vitro,cell adhesion experiments showed that cells could well spread on the surface of the material,furthermore the cells on the surface of P-PEIs material extended more cell pseudopodia under electron microscopy.Cell proliferation test showed that the proliferation rate of cells in P-PEIs group was significantly higher than that in other two groups(P < 0.05).Cytotoxicity test showed that all three groups of samples had no obvious toxicity.Conclusion:In this study,we searched the biocompatibility of PEI materials and successfully developed P-PEIs fabricated by a solvent casting method.The result proved that PEI materials have good biocompatibility and similar mechanical properties to bone.The interconnected pore structure of P-PEIs scaffolds provides sufficient space and environment for cell growth and promotes the interaction of cells,which indicates a potential application of PPEIs as an effective bone graft substitute for the treatment of bone regeneration.