title: In vitro degradation and fracture toughness of multilayered porous poly(propylene fumarate)/beta-tricalcium phosphate scaffolds.
abstract: This study investigated the in vitro degradation of poly(propylene fumarate)/beta-tricalcium phosphate (PPF/beta-TCP) scaffolds in pH 7.4 phosphate-buffered saline at 37 degrees C. Scaffold design consisted of three layers: two solid layers about a central layer of porous PPF foam. Solid PPF with molecular weights of 810 and 1450 Da was crosslinked under UV light. PPF foam was prepared by a photocrosslinking, porogen-leaching method with an initial porogen content of 80 wt % and two sizes, 150-300 and 300-500 microm. Comparison of initial and residual weights demonstrated a 14.3 +/- 2.0% loss of mass at 3 weeks and a 16.6 +/- 1.8% loss of mass at 6 weeks. Observed pH values for all constructs remained stable (7.15-7.40) throughout the 3 to 6 weeks. Scanning electron micrographs of these scaffolds revealed some loss of foam material between 3 and 6 weeks; however, foam microarchitecture was intact. Solid PPF fracture toughness was tested for high and low molecular weight PPF, 0.376 +/- 0.004 and 0.134 +/- 0.015 MPa(m)1/2, respectively. These values are roughly one magnitude less than human cortical bone.
authors: Division of Plastic Surgery, Department of Surgery and the Research Institute, University Hospitals of Cleveland, OH 44106-5044, USA.
authors: Michael S
authors: MS
authors: Wolfe
authors: David
authors: D
authors: Dean
authors: Jeffrey E
authors: JE
authors: Chen
authors: John P
authors: JP
authors: Fisher
authors: Seungho
authors: S
authors: Han
authors: Clare M
authors: CM
authors: Rimnac
authors: Antonios G
authors: AG
authors: Mikos
mesh_terms: D001696:Biomechanical Phenomena; D001843:Bone Cements / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry*; D005650:Fumarates / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D011126:Polypropylenes / Q000737:chemistry*; D016062:Porosity; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D001843:Bone Cements; D002130:Calcium Phosphates; D005650:Fumarates; D011126:Polypropylenes; C485817:beta-tricalcium phosphate; C097850:poly(propylene fumarate); C018392:tricalcium phosphate