From Garbage to Biomaterials: An Overview on Egg Shell Based Hydroxyapatite

Table 1

Comparison of HAp produced by various sources.

Parameters	Bovine bone	Fish bones	Eggshell	Natural bone
Ca/P ratio	>1.67	≥1.67	≥1.67	1.67
Particle size	Micro to nanometer range	In nanometer range	≥50 nm	Nanocomposite
Morphology	Needle, rod, plate, spherical, and so forth	Needle, rod, spherical, and so forth	Needle or rod	Needle or rod
Phase composition	Phase pure and tricalcium phosphate	Phase pure	Phase pure	Composite
Thermal stability	800–1000°C	600–800°C	<800°C	>1200°C
Trace elements	Na^+, Mg^2+, K^+, Ti^2+, etc	Fe^3+, Cr^3+, Cu^2+, K^+, Mg^2+, and so forth	major; Element Mg^2+, Na^+	Na^+, Mg^2+, K^+; Zn^2+,