Synthesis and characterization of composite poly(1.8 octanediol Co-Citrate) (POC)/nano-hydroxyapatite as candidate biodegradable bone screw

The high number of bone fractures, around 300-400 cases per month, are treated with orthopedic surgery method using internal fixation by bone screw which is aimed at accelerating patients' mobilization. There is a necessity to invent biomaterial which possesses two main characteristics: biocompatible and biofunctional, as well as having an important element of biodegradable without conducting reoperation. A research focused on the various composition of nano-hydroxyapatite (HA) derived from extracted snapper fish scales on Poly (1,8-octanediol-Co-Citrate (POC) as Biodegradable Bone screw. This research is purported to synthesize Poly (1,8-Octanediol-co-Citrate (POC) and characterize the influence of HA compositions against mechanical properties and compatibility of POC-HA composite that enable it to be used as Biodegradable Bone screw material. The condensation polymerization method is applied in synthesizing POC to produce POC pre-polymer by the formation of an ester bond group C=O stretch at 1731 cm-1 through a test of functional groups (FTIR). POC pre-polymer is composited with nano-HA compositions of 62%, 65%, 68% and 71% and followed by post-polymerization treatment. POC-HA composites formed were tested on hardness and biodegradability. The results obtained indicate that the composition of HA nanoparticles influences the mechanical properties and biocompatibility of the material. Best results were from 62% HA composition in which the hardness value was of 885.57 MPa, close to that of bone hardness which is 150-664 MPa. Results also showed that the rate of biodegradation reached 3.42% (4 weeks) which is in accordance to fracture bone grafting period of 21 months. Based on the characteristics result indicated in this study, the composite of Poly (1,8-Octanediol-co-Citrate) (POC)-Nano Hydroxyapatite is a potential candidate for biodegradable bone screw material.