Effect of silver (Ag) substitution nano-hydroxyapatite synthesis by microwave processing

Synthetic hydroxyapatite, (HA, Ca₁₀(PO₄)₆(OH)₂), is an attractive and widely utilized bio-ceramic material for orthopedic and dental implants because of its close resemblance of native tooth and bone crystal structure. This HA can be used in bio-implants as well as drug delivery application due to the unique properties of HA. Biomaterials synthesized from the natural species like mussel shells have additional benefits such as high purity, less expensive and high bio compatibility. In this project, a mussel shells were extracted to produce calcium oxide (CaO) sample. The efficient temperature to produced CaO is 1000°C in 90 minutes. The different contents of silver (0.5AgHA - 6AgHA) are prepared to check the extent of silver substitution for calcium in the HA. Then the mixtures of silver nitrate and CaO are subjected into microwave for 900 W in 30 minutes. The AgHA powder samples were characterized by X-ray diffraction (XRD) technique and also scanning electron microscope (SEM). From SEM analysed, AgHA particles had shown the shape likes needle morphology. In addition, the particles showed high tendency to agglomerate and not dependent on the amount of silver content. From XRD analysed, the samples with Ag content ≥ 0.3 shows the Ag peak clearly at 2θ~38.2°. The crystalline size of AgHA from microwave processing is around 14.96 nm - 23.03 nm and does not effected by contents of silver.