بررسي پايداري نانوهيدروكسي آپاتيت توليد شده به روش رسوبي تحت شرايط استريل

Investigation on Stability of Nano-Hydroxyapatite Produced Using Precipitation Method at Strile Condition

To produce nano size hydroxyapatite aqueous solutions of calcium hydroxide and ortho-phosphoric acid were used as reactants. firstly, an aqueous suspension of ortho-phosphoric acid was slowly added gradually to an aqueous suspension of Ca(OH)2 while stirring vigorously. Concentrated NaOH was added until a final pH of 10 was obtained. The obtained material was washed using deionized water and dried in oven at 85°C for 24 h and milled using a planetary ball mill. X-ray diffraction (XRD), thermo gravimetry analysis (TGA) tests were done to elucidate crystallinity and thermal behaviour of produced nano size hydroxyapatite respectively. Transmission electron microscope (TEM) was used to investigate the particle size. The results of XRD and TEM tests proved that the produced hydroxyapatite is in nano scale with grain size of about 30 nm. The results of TGA test showed that the percentage of weight loss of all powders retained at -23, 25 and 160°C is less than 5% showing little dependency of degradation on retained temperature.