Journal of Materials Science: Materials in Medicine

, Volume 22, Issue 11, pp 2413–2427 | Cite as

Hydroxyapatite nanorod-reinforced biodegradable poly(l-lactic acid) composites for bone plate applications

  • Erkin Aydin
  • Josep A. Planell
  • Vasif Hasirci


Novel PLLA composite fibers containing hydroxyapatite (HAp) nanorods with or without surface lactic acid grafting were produced by extrusion for use as reinforcements in PLLA-based bone plates. Fibers containing 0–50% (w/w) HAp nanorods, aligned parallel to fiber axis, were extruded. Lactic acid surface grafting of HAp nanorods (lacHAp) improved the tensile properties of composites fibers better than the non-grafted ones (nHAp). Best tensile modulus values of 2.59, 2.49, and 4.12 GPa were obtained for loadings (w/w) with 30% lacHAp, 10% nHAp, and 50% amorphous HAp nanoparticles, respectively. Bone plates reinforced with parallel rows of these composite fibers were molded by melt pressing. The best compressive properties for plates were obtained with nHAp reinforcement (1.31 GPa Young’s Modulus, 110.3 MPa compressive strength). In vitro testing with osteoblasts showed good cellular attachment and spreading on composite fibers. In situ degradation tests revealed faster degradation rates with increasing HAp content. To our knowledge, this is the first study containing calcium phosphate–polymer nanocomposite fibers for reinforcement of a biodegradable bone plate or other such implants and this biomimetic design was concluded to have potential for production of polymer-based biodegradable bone plates even for load bearing applications.


Lactic Acid Ultimate Tensile Strength PLLA Composite Fiber Bone Plate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



We gratefully acknowledge the support by the Scientific and Technical Research Council of Turkey (TUBITAK) (TBAG 105T508) and METU BAP.


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Erkin Aydin
    • 1
    • 2
  • Josep A. Planell
    • 4
  • Vasif Hasirci
    • 1
    • 2
    • 3
  1. 1.BIOMATENMETU Center of Excellence in Biomaterials and Tissue EngineeringAnkaraTurkey
  2. 2.Department of Biotechnology, Biotechnology Research UnitMETUAnkaraTurkey
  3. 3.Department of Biological Sciences, Biotechnology Research UnitMETUAnkaraTurkey
  4. 4.Institute for Bioengineering of Catalonia (IBEC)BarcelonaSpain

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