Fast route for synthesis of stoichiometric hydroxyapatite by employing the Taguchi method

authors	Ben-Arfa, BAE; Salvado, IMM; Frade, JR; Pullar, RC
nationality	International
journal	MATERIALS & DESIGN
author keywords	Hydroxyapatite; Nanoparticles; Nanosynthesis; Biomaterials; Biocompatibility; Taguchi method
keywords	SOL-GEL METHOD; CALCIUM HYDROXYAPATITE; NANOPARTICLES; POWDERS; PRECIPITATION; TEMPERATURE; MORPHOLOGY; PH
abstract	The Taguchi experimental design method is an elegant and efficient way of deriving optimum conditions for processes from the minimum number of experiments. We correlated various relevant synthesis parameters in the precipitation synthesis of single-phase pure hydroxyapatite (Ca-10(PO4)(6)(OH)(2), HAp) nanoparticles, via a rapid wet precipitation method, without any aging time. Taguchi planning was used for a systematic study of the combined effects of five different parameters: pH, synthesis temperature, synthesis time, drying temperature and calcination temperature. Using T\aguchi methods, we were able to evaluate the effects of four variations (levels) in each of these five parameters, with just 16 experiments (an L-16 (1024) orthogonal array). We assessed the impact of these parameters on four distinct properties, namely crystallite size, surface area, Ca/P atomic ratio and mol% of HAp. Calcination temperature exerted the greatest impact on hydroxyapatite morphology, corresponding to crystallite size and specific surface area, for which the role of other processing parameters was not significant. On the contrary, the Ca:P ratio was affected mainly by pH. These findings were confirmed by microstructural, structural and spectroscopic characterisation. FTIR spectra, revealing the conditions to retain a pure or prevailing hydroxyapatite phase, and also to indicate favourable conditions for A-type substitutions of carbonate for hydroxide groups, or B-type substitution for phosphate groups. (C) 2016 Elsevier Ltd. All rights reserved.
publisher	ELSEVIER SCI LTD
issn	0264-1275
year published	2016
volume	109
beginning page	547
ending page	555
digital object identifier (doi)	10.1016/j.matdes.2016.07.083
web of science category	Materials Science, Multidisciplinary
subject category	Materials Science
unique article identifier	WOS:000384105000059