title: Bi-layered constructs of poly(glycerol-sebacate)-β-tricalcium phosphate for bone-soft tissue interface applications.
abstract: This study aims to establish a facile protocol for the preparation of a bi-layered poly(glycerol-sebacate) (PGS)/β-tricalcium phosphate (β-TCP) construct and to investigate its potential for bone-soft tissue engineering applications. The layered structure was prepared by distributing the ceramic particles within a prepolymer synthesized in a microwave reactor followed by a cross-linking of the final construct in vacuum (<10mbar). The vacuum stage led to the separation of cross-linked elastomer (top) and ceramic (bottom) phases. Results showed that addition of β-TCP particles to the elastomer matrix after the polymerization led to an increase in compression strength (up to 14±2.3MPa). Tensile strength (σ), Young's modulus (E), and elongation at break (%) values were calculated as 0.29±0.03MPa and 0.21±0.03; 0.38±0.02 and 1.95±0.4; and 240±50% and 24±2% for PGS and PGS/β-TCP bi-layered constructs, respectively. Morphology was characterized by using Scanning Electron Microscopy (SEM) and micro-computed tomography (μ-CT). Tomography data revealed an open porosity of 35% for the construct, mostly contributed from the ceramic phase since the elastomer side has no pore. Homogeneous β-TCP distribution within the elastomeric structure was observed. Cell culture studies confirmed biocompatibility with poor elastomer-side and good bone-side cell attachment. In a further study to investigate the osteogenic properties, the construct were loaded with BMP-2 and/or TGF-β1. The PGS/β-TCP bi-layered constructs with improved mechanical and biological properties have the potential to be used in bone-soft tissue interface applications where soft tissue penetration is a problem.
authors.affiliation: Bioengineering Division, Institute of Science and Engineering, Hacettepe University, Ankara, Turkey.
authors.forename: Atakan
authors.initials: A
authors.lastname: Tevlek
authors.affiliation: Nanotechnology and Nanomedicine Division, Institute of Science and Engineering, Hacettepe University, Ankara, Turkey.
authors.forename: Pezhman
authors.initials: P
authors.lastname: Hosseinian
authors.affiliation: Nanotechnology and Nanomedicine Division, Institute of Science and Engineering, Hacettepe University, Ankara, Turkey.
authors.forename: Cansel
authors.initials: C
authors.lastname: Ogutcu
authors.affiliation: Biology Department, Kirikkale University, Kirikkale, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Turk
authors.affiliation: Environmental Engineering Department, Bioengineering Division, Centre for Bioengineering, Hacettepe University, Ankara, Turkey. Electronic address: hmaydin@hacettepe.edu.tr.
authors.forename: Halil Murat
authors.initials: HM
authors.lastname: Aydin
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology; D055396:Bone Morphogenetic Protein 2 / Q000378:metabolism; D001842:Bone and Bones / Q000378:metabolism; D002130:Calcium Phosphates / Q000737:chemistry*; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D003651:Decanoates / Q000737:chemistry*; D055119:Elastic Modulus; D005990:Glycerol / Q000031:analogs & derivatives* / Q000737:chemistry; D051379:Mice; D018613:Microscopy, Confocal; D008855:Microscopy, Electron, Scanning; D011108:Polymers / Q000737:chemistry*; D013718:Tensile Strength; D023822:Tissue Engineering; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D055114:X-Ray Microtomography
chemical_list: D001672:Biocompatible Materials; D055396:Bone Morphogenetic Protein 2; D002130:Calcium Phosphates; D003651:Decanoates; D011108:Polymers; D053773:Transforming Growth Factor beta1; C485817:beta-tricalcium phosphate; C469892:poly(glycerol-sebacate); D005990:Glycerol
keywords: Bi-layered; Guided bone regeneration (GBR); Poly(glycerol-sebacate); Tissue engineering; β-tricalcium phosphate