title: Hydroxyapatite reinforced poly(3-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) based degradable composite bone plate.
abstract: Poly(3-hydroxybutyrate) (P3HB), its co-polymers with 3-hydroxyvalerate (HV) (PHBV8 and PHBV22), and their hydroxyapatite (HAp) containing composites (5 and 15%, w/w) were prepared by injection molding. PHBV bone plates with low valerate contents and 15% (w/w) HAp appear to have better mechanical properties than the others. Flexural strengths of 15% (w/w) HAp-loaded P3HB, PHBV8 and PHBV22 were 78.28, 63.45 and 39.38 MPa, respectively. Tensile strengths of 15% (w/w) HAp-loaded P3HB, PHBV8 and PHBV22 were 18.99, 15.44 and 11.02 MPa, respectively. For the ageing test, bone plates were incubated in phosphate-buffered saline PBS (0.1 M, pH 7.4) at 37 degrees C and at pre-determined time points they were removed and subjected to a three-point bending test. Incubation in PBS caused a sharp decrease in the mechanical properties within the first 24 h, followed either by a gradual decrease or no change for a period of about 1 month. SEM results showed that there was no significant material erosion in the 4-week incubation period. P3HB loaded with 15% HAp appeared to yield the most suitable bone plate, insofar as mechanical properties are concerned with potential for further testing in vivo.
authors.affiliation: Biotechnology Research Unit, Department of Biological Sciences, Middle East Technical University, 06531 Ankara, Turkey.
authors.forename: Suleyman
authors.initials: S
authors.lastname: Coskun
authors.forename: Feza
authors.initials: F
authors.lastname: Korkusuz
authors.forename: Vasif
authors.initials: V
authors.lastname: Hasirci
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry*; D001673:Biodegradation, Environmental; D001860:Bone Plates; D006882:Hydroxyapatites / Q000737:chemistry*; D006885:Hydroxybutyrates / Q000737:chemistry*; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D018583:Pliability; D011091:Polyesters / Q000737:chemistry*; D013718:Tensile Strength; D013997:Time Factors; D000094122:Polyhydroxybutyrates
chemical_list: D001672:Biocompatible Materials; D006882:Hydroxyapatites; D006885:Hydroxybutyrates; D011091:Polyesters; C052620:poly(3-hydroxybutyrate)-co-(3-hydroxyvalerate); D000094122:Polyhydroxybutyrates; C003182:poly-beta-hydroxybutyrate