title: Development and characterization of a biodegradable polyphosphate.
abstract: A biodegradable polyphosphate polymer (Mn = 18,000, Mw/Mn = 3.2) matrix system was developed as a potential delivery vehicle for growth factors. As a model system, release of recombinant human osteogenic protein-1 (OP-1) from this polymer was evaluated. The polyphosphate was synthesized using a triethylamine catalyst in an argon environment, and characterized using elemental analysis, gel permeation chromatography (GPC), and Fourier transform infrared spectroscopy (FTIR). Degradation kinetics of the polyphosphate polymer in phosphate-buffered saline (PBS) were represented by a second-order polynomial while degradation in bovine serum was linear with time. The polymer degraded faster in PBS than in bovine serum. In vitro release of OP-1 was also faster in PBS than in serum. Release kinetics of OP-1 in PBS and serum were represented by second-order polynomials. The OP-1 release from this physically dispersed polymeric matrix may be described by several possible mechanisms: diffusion, bulk polymer degradation, ion complexation, and interactions among the protein (OP-1), polymer, proteins, and enzymes in the media. This polyphosphate may be an effective carrier for morphogens, growth factors, or other classes of bioactive molecules.
authors.affiliation: Department of Biologic and Materials Sciences, School of Dentistry, University of Michigan, Ann Arbor 48109-1078, USA.
authors.forename: M L
authors.initials: ML
authors.lastname: Renier
authors.forename: D H
authors.initials: DH
authors.lastname: Kohn
mesh_terms: D000818:Animals; D001559:Benzhydryl Compounds; D001672:Biocompatible Materials / Q000737:chemistry*; D001673:Biodegradation, Environmental; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000737:chemistry; D002417:Cattle; D006801:Humans; D006868:Hydrolysis; D008970:Molecular Weight; D010636:Phenols / Q000737:chemistry; D011122:Polyphosphates / Q000737:chemistry*; D011994:Recombinant Proteins / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D016212:Transforming Growth Factor beta / Q000737:chemistry; D000098826:Bisphenol A Compounds
chemical_list: D001559:Benzhydryl Compounds; D001672:Biocompatible Materials; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D010636:Phenols; D011122:Polyphosphates; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C525819:BMP7 protein, human; C006780:bisphenol A; D000098826:Bisphenol A Compounds