Development of Novel Biodegradable Amino Acid Ester Based Polyphosphazene-Hydroxyapatite Composites for Bone Tissue Engineering

Hydroxyapatite formed from low temperature setting calcium phosphate cements (CPC) are currently been used for various orthopaedic applications. CPCs are attractive candidates for the development of scaffolds for bone tissue engineering, since they are moldable, resorbable, set at physiological temperature without the use of toxic chemicals, and can be processed in an operating room setting. However they may have mechanical disadvantages which seriously limit them to non-load bearing orthopaedic applications, The aim of the present study was to develop composites from ployphosphazenes and calcium deficient hydroxyapatite precursors to form poorly crystalline hydroxyapatite-polymer composites. Composites were formed from calcium deficient hydroxyapatite precursors (Ca/P - 1.5, 1.6) and biodegradable polyphosphazenes, polyBIS(ETHYL ALANATO)PHOSPHAZENE (PNEA50mPh50) at physiological temperature. The results demonstrated that poorly crystalline hydroxyapatite that resembled the mineral component of bone was formed in the presence of biodegradable polyphosphazenes. The surface morphology of all the four composites was identical with a porous microstructure. The composites supported the adhesion and proliferation of osteoblast like MC3T3-E1 cells making them potential candidates for bone tissue engineering.
Presented at the Nanoscale Materials Science in Biology and Medicine held in Boston, MA on 28 Nov-2 Dec 2004. Pub. in Materials Research Society Symposium Proceedings, v845 p291-296, 2005. ISBN 1-55-899-793-8. This article is from ADA434631 Materials Research Society Symposium Proceedings. Volume 845, 2005. Nanoscale Materials Science in Biology and Medicine, Held in Boston, MA on 28 November-2 December 2004