Effect of Surface-activated PLLA Scaffold on Apatite Formation in Simulated Body Fluid

Polymer–ceramic composite coatings on magnesium-based alloys have attracted lots of attention in recent years, to control the speed of degradability and to enhance bioactivity and biocompatibility. In this study, to decrease the corrosion rate in a simulated body fluid (SBF) solution for long periods, to control degradability, and to enhance bioactivity, polycaprolactone–chitosan composite coatings with different percentages of baghdadite (0 wt.%, 3 wt.%, and 5 wt.%) were applied to an anodized AZ91 alloy. According to the results of the immersion test of the composite coating containing 3 wt.% baghdadite in a phosphate buffer solution (PBS), the corrosion rate decreased from 0.45 (for the AZ91 sample) to 0.11 mg/cm2·h after seven days of immersion. To evaluate the apatite formation capability of specimens, samples were immersed in an SBF solution. The results showed that the samples were bioactive as apatite layers formed on the surface of specimens. The composite coating containing 3 wt.% baghdadite showed the highest apatite-formation capability, with a controlled release of ions, and the lowest corrosion rate in the SBF.

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Effect of Annealing on Microstructure of Hydroxyapatite Coatings and their Behaviours in Simulated Body Fluid

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.922.657 ◽

2014 ◽

Vol 922 ◽

pp. 657-662 ◽

Cited By ~ 6

Author(s):

Sharidah Azuar Abdul Azis ◽

John Kennedy ◽

Peng Cao

Keyword(s):

Heat Treatment ◽

Simulated Body Fluid ◽

Body Fluid ◽

Ion Beam ◽

Apatite Formation ◽

Ion Beam Sputtering ◽

Different Temperatures ◽

Higher Temperature ◽

Xrd Patterns ◽

Post Deposition

In this study, hydroxyapatite (HA) coatings on Ti6Al4V substrate were deposited using an ion beam sputtering technique. Owing to its medical applications, the crystalline phases present in the HA must be controlled. This study investigated the effect of post-deposition heat treatment at different temperatures and evaluated the microstructure of the HA coatings and their behaviours in simulated body fluid (SBF). The post-deposition treatment of the as-deposited samples was carried out in an air-circulated furnace at a temperature between 3000C and 6000C. The XRD patterns reveal that the minimum temperature to transform the HA coating from amorphous to crystalline phase is 4000C. A higher temperature at 6000C leads to a growth of the crystalline HA phases. Fourier transform infrared spectroscopy (FTIR) measurements show the existence of hydroxyl and PO-bonds in all coatings and the amounts varied with temperature. Atomic Force Microscopy (AFM) study suggests that the nanostructured crystalline HA starts to grow at 4000C and becomes more obvious at a higher temperature of 6000C. The simulated body fluid (SBF) test reveals that better apatite formation with post deposition heat treatment at 6000C would potentially enhance the formation of new bone (osseointegration).

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