In Vitro Deposition of Hydroxyapatite on Cortical Bone Collagen Stimulated by Deformation-Induced Piezoelectricity

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• 作者：Karem Noris-Suá ; rez ; Joaquin Lira-Olivares ; Ana Marina Ferreira ; Jos&eacute ; Luis Feijoo ; Nery Suá ; rez ; Maria C. Herná ; ndez ; Esteban Barrios
• 刊名：Biomacromolecules
• 出版年：2007
• 出版时间：March 2007
• 年：2007
• 卷：8
• 期：3
• 页码：941 - 948
• 全文大小：614K
• 年卷期：v.8,no.3(March 2007)
• ISSN：1526-4602

文摘

In the present work, we have studied the effect of the piezoelectricity of elastically deformed cortical bone collagenon surface using a biomimetic approach. The mineralization process induced as a consequence of the piezoelectricityeffect was evaluated using scanning electron microscopy (SEM), thermally stimulated depolarization current(TSDC), and differential scanning calorimetry (DSC). SEM micrographs showed that mineralization occuredpredominantly over the compressed side of bone collagen, due to the effect of piezoelectricity, when the samplewas immersed in the simulated body fluid (SBF) in a cell-free system. The TSDC method was used to examinethe complex collagen dielectric response. The dielectric spectra of deformed and undeformed collagen sampleswith different hydration levels were compared and correlated with the mineralization process followed by SEM.The dielectric measurements showed that the mineralization induced significant changes in the dielectric spectraof the deformed sample. DSC and TSDC results demonstrated a reduction of the collagen glass transition as themineralization process advanced. The combined use of SEM, TSDC, and DSC showed that, even without osteoblastspresent, the piezoelectric dipoles produced by deformed collagen can produce the precipitation of hydroxyapatiteby electrochemical means, without a catalytic converter as occurs in classical biomimetic deposition.