Bionanohydroxyapatite/Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) composites with improved particle dispersion and superior mechanical properties

Rai, B., Noohom, W., Kithva, P.H., Grondahl, L. and Trau, M. (2008) Bionanohydroxyapatite/Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) composites with improved particle dispersion and superior mechanical properties. Chemistry of Materials, 20 8: 2802-2808. doi:10.1021/cm703045u


Author Rai, B.
Noohom, W.
Kithva, P.H.
Grondahl, L.
Trau, M.
Title Bionanohydroxyapatite/Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) composites with improved particle dispersion and superior mechanical properties
Formatted title
Bionanohydroxyapatite/Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) composites with improved particle dispersion and superior mechanical properties
Journal name Chemistry of Materials   Check publisher's open access policy
ISSN 0897-4756
Publication date 2008-03-15
Year available 2008
Sub-type Article (original research)
DOI 10.1021/cm703045u
Open Access Status Not yet assessed
Volume 20
Issue 8
Start page 2802
End page 2808
Total pages 7
Place of publication United States
Publisher American Chemical Society
Language eng
Subject C1
030603 Colloid and Surface Chemistry
920116 Skeletal System and Disorders (incl. Arthritis)
Abstract The present work was inspired by a persistent limitation in the use of composite biomaterials for orthopedics, namely, the tendency of ceramic reinforcements to agglomerate in these composites due to interparticle van der Waals interaction. As a result, the composites possess poor mechanical properties that are unsuited for load-bearing applications. We propose using nanohydroxyapatite particles preadsorbed with heparin (nHA-HEP) to circumvent this issue. The key feature was the dual role that HEP would play in enhancing particle dispersion and biological response. Turbidity and zeta potential measurements revealed that the addition of HEP significantly improved the colloidal stability (23 days with minimal particle sedimentation) of nHA in water, dimethylfomiamide (DNIF), and dimethylsulfoxide, (DMSO) but had negligible effect in acetic acid. Anti-FXa activity results showed that 95% of the HEP adsorbed onto nHA retained its bioactivity in DMSO and water, while 51% was preserved in DMF and acetic acid. Composite fabrication was ultimately done using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), a biodegradable polymer, dissolved in DMF. A decrease in water contact angle of solvent cast films with increasing weight percent (wt %) of nHA-HEP/PHBV was observed as compared to nHA/PHBV films. Scanning electron micrographs illustrated that nHA/PHBV films had poor dispersion of particles within the matrix and that large agglomerates settled to the bottom of the films during casting. On the contrary, the nHA-HEP/PHBV matrices had effective dispersion of particles and enhanced tensile properties. We found that the tensile elastic modulus and strength of the films increased with increasing wt % of nHA-HEP: A value close to the human cortical bone was obtained at 30 wt % loading of nHA-HEP. In conclusion, understanding the relationship between process, morphology, and property led to the development of nHA-HEP/PHBV composites that show promise for load-bearing bone applications.
Keyword Chemistry, Physical
Materials Science, Multidisciplinary
Chemistry
Materials Science
CHEMISTRY, PHYSICAL
MATERIALS SCIENCE, MULTIDISCIPLINARY
Q-Index Code C1
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Journal Article
Sub-type: Article (original research)
Collections: 2009 Higher Education Research Data Collection
School of Chemistry and Molecular Biosciences
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 23 times in Thomson Reuters Web of Science Article | Citations
Scopus Citation Count Cited 27 times in Scopus Article | Citations
Google Scholar Search Google Scholar
Created: Mon, 30 Mar 2009, 23:28:56 EST by Glenda Chown on behalf of School of Chemistry & Molecular Biosciences