Electrophoretic Deposition of Nanocrystalline Calcium Phosphate Coating for Augmenting Bioactivity of Additively Manufactured Ti-6Al-4V

Calcium phosphate coating films were fabricated on Ti-6Al-4V plates and screw-type implants with a blast-treated surface using radiofrequency (RF) magnetron sputtering and were evaluated in vitro and in vivo. Amorphous calcium phosphate (ACP) and oxyapatite (OAp) films obtained in this study could cover the blast-treated substrate very efficiently, maintaining the surface roughness. For the in vitro evaluations of the calcium phosphate coating films, bonding strength and alkaline phosphatase (ALP) activity were examined. The bonding strength of the coating films to a blast-treated substrate exceeded 60 MPa, independent of film phases except for the film after post-heat-treatment in silica ampoule. When compared with an uncoated substrate, the increase in the ALP activity of osteoblastic SaOS-2 cells on a calcium phosphate coated substrate was confirmed by a cell culture test. The removal torque of screw-type Ti-6Al-4V implants with a blast-treated surface from the femur of Japanese white rabbit increased with the duration of implantation and it was statistically improved by coating an ACP film 2 weeks after implantation. The in vitro and in vivo studies suggested that the application of the sputtered ACP film as a coating on titanium implants was effective in improving their biocompatibility with bones.

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The effect of graphene oxide on surface features, biological performance and bio-stability of calcium phosphate coating applied by pulse electrochemical deposition

Applied Surface Science ◽

10.1016/j.apsusc.2017.12.133 ◽

2018 ◽

Vol 437 ◽

pp. 122-135 ◽

Cited By ~ 21

Author(s):

Leila Fathyunes ◽

Jafar Khalil-Allafi

Keyword(s):

Graphene Oxide ◽

Calcium Phosphate ◽

Electrochemical Deposition ◽

Calcium Phosphate Coating ◽

Phosphate Coating ◽

Surface Features ◽

Biological Performance

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Calcium Phosphate Coated Rapid Prototyped Porous Titanium Scaffolds

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.361-363.907 ◽

2007 ◽

Vol 361-363 ◽

pp. 907-910

Author(s):

Marco A. Lopez-Heredia ◽

Borhane H. Fellah ◽

Paul Pilet ◽

C. Leroux ◽

M. Dorget ◽

...

Keyword(s):

Bone Marrow ◽

Calcium Phosphate ◽

Polarized Light ◽

Porous Titanium ◽

Calcium Phosphate Coating ◽

Phosphate Coating ◽

Alamar Blue ◽

Subcutaneous Implantation ◽

Marrow Mesenchymal Stem Cells ◽

Rat Bone

Porous Titanium Scaffolds were produced by using a rapid prototyping technique. These scaffolds were either coated or not with a calcium phosphate coating via an eletrodeposition method. Rat bone marrow mesenchymal stem cells were cultured on the scaffolds at a density of 106 cells/scaffold for a period of 3 days. Cell proliferation was measured by using the Alamar Blue assay. The scaffolds were observed by SEM and polarized light microscopy. Constructs were then implanted subcutaneously for 4 weeks in syngenic rats. Cells proliferated well after seeding. After subcutaneous implantation, histology and SEM revealed the presence of uniform coatings as well as Ca and P deposits in the non-coated scaffolds suggesting mineralization.

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Hydrothermal Growth of Nano-Hydroxyapatite Coating Formed on Fluorinated Magnesium Alloy and Its Corrosion Behaviour

Science of Advanced Materials ◽

10.1166/sam.2021.3842 ◽

2021 ◽

Vol 13 (1) ◽

pp. 10-19

Author(s):

Chun-Yan Zhang ◽

Hao-Lan Fang ◽

Xin-Peng Liu ◽

Fan-Cheng Meng ◽

Zhong-Qing Tian ◽

...

Keyword(s):

Magnesium Alloy ◽

Calcium Phosphate ◽

Hydrothermal Treatment ◽

Treatment Time ◽

Electrochemical Impedance ◽

Hydrothermal Growth ◽

Crystal Phase ◽

Calcium Phosphate Coating ◽

Phosphate Coating ◽

Ha Coating

In order to explore the hydrothermal growth mechanism of hydroxyapatite (HA) coating on fluorinated magnesium alloy, the changes of morphology, composition and crystal phase of the calcium phosphate coating during the hydrothermal treatment were studied. And the change of electrochemical impedance spectroscopy (EIS) of the coating specimen of different hydrothermal treatment time was discussed to further understanding the change of the coating structure. The results demonstrated that calcium phosphate could rapidly nucleate on fluorinated AZ31 magnesium alloy. The crystal phase of calcium phosphate coating was mainly octacalcium phosphate (OCP) at the early stage of hydrothermal treatment. Then the content of OCP decreased and the content of HA increased with hydrothermal time. The coating consisted of only HA after hydrothermal treatment for about 4h. The HA coating composed of rod-like crystals exhibited an obvious double layer structure. The rod-like crystals of inner layer arranged into dense bundles and the rod-like crystals of outer layer arranged into loose chrysanthemum-like clusters. Fluoride conversion layer acted as an intermediate transition layer to connect magnesium alloy and HA coating into a whole. The results of immersion test in simulated body fluid demonstrated that HA crystals dissolved slowly. No peeling occurred of HA coating during the 12 days' immersion. Pitting corrosion was still the mainly corrosion mode of magnesium alloy substrate due to the electrolyte infiltration during the immersion.

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