Preparation and characterization of hydroxyapatite/poly(ethylene glutarate) biomaterials

✍ Scribed by Punnama Siriphannon; Pathavuth Monvisade; Supatra Jinawath; Khemchai Hemachandra

• Publisher: John Wiley and Sons
• Year: 2007
• Tongue: English
• Weight: 899 KB
• Volume: 81A
• Category: Article
• ISSN: 1549-3296
• DOI: 10.1002/jbm.a.31032

✦ Synopsis

Abstract

Hydroxyapatite/poly(ethylene glutarate) (HAp/PEG) biomaterial composites were prepared by ring‐opening polymerization (ROP) of cyclic oligo(ethylene glutarate) (C‐PEG) in porous HAp scaffolds. The HAp/C‐PEG precomposites were prepared by immersing the porous HAp scaffolds in the mixture solution of C‐PEG and dibutyl tinoxide catalyst overnight and polymerizing at 200°C for 24, 48, and 72 h under vacuum. The successful ROP of C‐PEG in the porous HAp scaffolds was corroborated by the signals of hydroxyl end‐group of PEG shown in the ^1^H NMR spectrum of the ROP‐products extracted from the composites. PEG in the composites was present as a thin layer coating on the HAp grains and was evenly distributed throughout the samples. The PEG content was about 13–16 wt % and decreased with increasing polymerization time. Its molecular weight (M̄~w~, weight average) measured by gel permeation chromatography was in the range of 4300–6800 g/mol. Compressive strength of the HAp/PEG composites was significantly increased from 3 MPa of the porous HAp scaffold to 11–15 MPa, depending on the PEG content in the composites. In vitro bioactivity of the HAp/PEG composites was studied by soaking in simulated body fluid (SBF) at 36.5°C for 7–28 days. After prolonged soaking, the HAp nanocrystals precipitated from the SBF solution and formed as a layer of globular aggregates, coated on the composite surfaces. This result suggested that the HAp/PEG composite was a bioactive material. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res, 2007