Insight into Biological Apatite: Physiochemical Properties and Preparation Approaches

Table 2

Preparation of biological apatite with thermal treatment.

Authors	Raw material	Particle size	Pretreatment	Temperature (°C)	Annealing time	Crystal
						Size	Morphology	Identity	Ca/P
Seo et al. [17]	Commercial bone ash powder	5–10 𝜇m	Immersion in NaOH	1000	1 h	0.5–1.0 𝜇m	Irregular	HAp + α-TCP	1.73
Janus et al. [11]	Porcine bone		Boiling; Leaching in NaOH	800; 1200		70–700 nm		HAp (800°C); HAp + CaO (1200°C)	1.709 (800°C); 1.675 (1200°C)
Barakat et al. [5]	Bovine bone	<450 𝜇m	Washing with acetone	850	1 h	0.1–0.25 𝜇m		HAp	1.65
Seo and Lee [58]	Human teeth			900	1 h			HAp	1.63
Ooi et al. [16]	Bovine bone	10 * 5 * 5 mm^3		400, 500, 600, 700, 800, 900, 1000, 1100, 1200	2 h			HAp (<1000°C); HAp + β-TCP (>1000°C)	>1.67
Rhee et al. [61]	Bovine bone		Degreasing and deproteinization	600, 800, 1000	3 h	50 nm (600°C); 1 𝜇m (1000°C)
Murugan et al. [57]	Bovine bone		Degreasing; hydrothermal treatment in NaOH	500	Overnight	12 nm		HAp-CO3
Danilchenko et al. [8]	Bovine bone	3 * 5 * 20 mm^3 block and powder		100, 600, 700, 800, 900, 1000, 1100, 1300	45 min	Fast growth into big crystals (>200 nm, 𝑡>600°C)		HAp (<700°C); HAp + CaO + MgO (>700°C)
Kim et al. [14]	Porcine bone	15 * 15 * 15 mm^3	Immersion in H2O2 and alcohol	1300	2 h			HAp + β-TCP (oxygen-poor environment) HAp (oxygen-rich environment)	1.49 (oxygen-poor environment); 1.66 (oxygen-rich environment)
Murugan et al. [37]	Bovine bone		Degreasing in acetone-ether mixture	700	Overnight			HAp
Pan et al. [62]	Rat cortical bone		Immersion in H2O2 rinsed in deionized water and absolute ethanol and then dried, then being chilled in liquid nitrogen and pulverized	600	24 h	30–40 nm	Short rod	HAp-CO3 with trace Na and Mg	1.63 ± 0.04