caa a22 4500 463225031 CHVBK 20180405153224.0 cr unu---uuuuu 170326e20070601xx s 000 0 eng 10.1007/s10853-006-0636-0 doi (NATIONALLICENCE)springer-10.1007/s10853-006-0636-0 In situ synthesized ceramic-polymer composites for bone tissue engineering: bioactivity and degradation studies [Elektronische Daten] [Yusuf Khan, Emily Cushnie, John Kelleher, Cato Laurencin] As an alternative to current bone grafting strategies, a poly-lactide-co-glycolide/calcium phosphate composite microsphere-based scaffold has been synthesized by the direct formation of calcium phosphate within forming microspheres. It was hypothesized that the synthesis of low crystalline calcium phosphate within forming microspheres would provide a site-specific delivery of calcium ions to enhance calcium phosphate reprecipitation onto the scaffold. Both polymeric and composite scaffolds were incubated in simulated body fluid (SBF) for 8weeks, during which time polymer molecular weight, scaffold mass, calcium ion concentration of SBF, pH of SBF, and calcium phosphate reprecipitation was monitored. Results showed a 20% decrease in polymeric scaffold molecular weight compared to 11-14% decrease for composite scaffolds over 8weeks. Composite scaffold mass and SBF pH decreased for the first 2weeks but began increasing after 2weeks and continued to do so up to 8weeks, suggesting interplay between pH changes and calcium phosphate dissolution/reprecipitation. Free calcium ion concentration of SBF containing composite scaffolds increased 20-40% over control values within 4h of incubation but then dropped as low as 40% below control values, suggesting an initial burst release of calcium ions followed by a reprecipitation onto the scaffold surface. Scanning electron micrographs confirm calcium phosphate reprecipitation on the scaffold surface after only 3days of incubation. Results suggest the composite scaffold is capable of initiating calcium phosphate reprecipitation which may aid in bone/implant integration. Springer Science+Business Media, LLC, 2007 Khan Yusuf Department of Orthopaedic Surgery, School of Medicine, The University of Virginia, 400 Ray C. Hunt Drive, Suite 330, 22903, Charlottesville, VA, USA aut Cushnie Emily Department of Chemical Engineering, The University of Virginia, 22904, Charlottesville, VA, USA aut Kelleher John Department of Orthopaedic Surgery, School of Medicine, The University of Virginia, 400 Ray C. Hunt Drive, Suite 330, 22903, Charlottesville, VA, USA aut Laurencin Cato Department of Orthopaedic Surgery, School of Medicine, The University of Virginia, 400 Ray C. Hunt Drive, Suite 330, 22903, Charlottesville, VA, USA aut Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/12(2007-06-01), 4183-4190 0022-2461 42:12<4183 2007 42 10853 https://doi.org/10.1007/s10853-006-0636-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10853-006-0636-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Khan Yusuf Department of Orthopaedic Surgery, School of Medicine, The University of Virginia, 400 Ray C. Hunt Drive, Suite 330, 22903, Charlottesville, VA, USA aut NATIONALLICENCE 700 1- Cushnie Emily Department of Chemical Engineering, The University of Virginia, 22904, Charlottesville, VA, USA aut NATIONALLICENCE 700 1- Kelleher John Department of Orthopaedic Surgery, School of Medicine, The University of Virginia, 400 Ray C. Hunt Drive, Suite 330, 22903, Charlottesville, VA, USA aut NATIONALLICENCE 700 1- Laurencin Cato Department of Orthopaedic Surgery, School of Medicine, The University of Virginia, 400 Ray C. Hunt Drive, Suite 330, 22903, Charlottesville, VA, USA aut NATIONALLICENCE 773 0- Journal of Materials Science Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 42/12(2007-06-01), 4183-4190 0022-2461 42:12<4183 2007 42 10853 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer