Preparation And Characterization 3D Printing Scaffolds For Bone Tissue Engineering

The combination of bio-filler with synthetic polymers has been an exciting route for developing tissue engineering scaffolds,in particular for bone tissue regeneration.In this study,biocompatible polymer Polycaprolactone(PCL)and a new quaternary phosphonium salt-allyltriphenylphosphonium bromide(ATPB)and Oyster shell powder(OSP)were used as raw materials,the OSP was treated as bio-filler.All the scaffolds were produced using an additive manufacturing technique.We fabricated two types scaffolds,they were PCL/OSP bone tissue engineering scaffold and PCL/ATPB/OSP antibacterial bone tissue engineering scaffolds.Their structure and properties were analyzed by using modern ananlytical techniques and major conclusions are as follows:(1)All the printed lines we made had a uniformed thickness,the diameter were 1.75±0.2mm,the optimal printing temperature were at 150?.It can print smooth and never block the print nozzle at the optimal printing temperature.(2)The PCL/OSP bone tissue engineering scaffolds were all prepared by a 3D printing machine,all the 3D printed scaffolds hold a highly porous and interconnected pore structure with pore size around 600 to 750?m suitable for cell in growth.OSP distributed evenly in the scaffolds which help to improve the mechanical performance,protein adsorption capacity and mineralization ability,CCK-8 testing result indicated there was no significant cytotoxicity effect of the prepared scaffolds towards MG-63 cells,all the scaffolds show a well ALP activity.The PCL/OSP bone tissue engineering scaffolds were no acute systemic toxicity and organization toxicity to the KM mice,which indicated that they have favorable biocompatibility.(3)The PCL/ATPB/OSP antibacterial bone tissue engineering scaffolds were all prepared by a 3D printing machine,all the 3D printed scaffolds with a highly porous andinterconnected pore structure with pore size around 600 to 750?m suitable for cell in growth.ATPB loaded in OSP can not only keep the highly effective antibacterial properties,but also reduce its cell toxicity,improve the biocompatibility of the antibacterial agent,in addition,OSP was a bioactive filler,it will help to improve the Osteogenic activity of the scaffolds.Meanwhile the prepared scaffolds exhibited antibacterial activity toward E.coli and S.aureus.Those scaffolds show excellent biocompatibility and are biosafety,which is expected to be applied in bone regeneration.