An Investigation on the Effect of Morphologies on Corrosion Behaviour of Nanostructured Hydroxyapatite-Titania Scaffolds

Journal of Bionanoscience 01/2011; Vol-4:1-5. DOI: 10.1166/jbns.2010.1038

ABSTRACT The viable application of hydroxyapatite (HAp) scaffolds requires to posses the unison of properties:
porosity, bioactivity, mechanical toughness etc. Such properties strongly depend on the geometric
factors such as the size, morphology/microstructure of HAp. We have developed a hydrothermal
based approach to synthesize HAp-titania scaffold with different morphologies ranging from smooth
film to cauliflower to urchin like structures. The structural characterization by XRD reveals the formation
of HAp phase. The SEM analysis suggests the formation of HAp nanosheets or their subsequent
assembly when reaction carried out under basic conditions without and with the oxidizing
agent H2O2, respectively. The detailed investigation of corrosion behaviour of all HAp-titania scaffold
samples was undertaken by potentiodynamic technique in Ringer’s simulated body fluid solution at
close to human body temperature i.e., 37 �C. The shift in the OCP values of HAp-titania scaffold
samples towards nobler side and the relatively more posivite Ecorr values observed for these samples
than that of bare Ti-foil, suggesting superior corrosion resistance in case of HAp-titania scaffold
samples than that of bare Ti-foil. The detailed results on structural characterization and discussion
on corrosion behaviour of HAp-titania scaffold samples with different morphologies/microstructures
are presented.

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Available from: kamala kanta Nanda, Jul 03, 2015
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