Aloe vera extracted solution was prepared from a 35 g portion
of thoroughly washed aloe vera leaves which were finely cut
and boiled in 100 ml of de-ionized water. The resulting extract
was used as an aloe vera extract solution. The starting materials
were added slowly to 250 ml of the aloe vera extracted solution
under vigorous stir at 30 C to obtain a well dissolved solution.
Throughout the whole process described above, no pH adjustment
was made. Then, the mixed solution was continuously stirred at
150 C until dried precursor was obtained. In order to determine
the temperature of possible decomposition and crystallization of
the HAp, the dried precursor was subjected to thermo gravimetric-differential
thermal analysis (TG/DTA) (Pyris Diamond TG/
DTA, PerkinElmer Instrument). The crystallization seemed to occur
at temperature above 550 C as shown by the TG/DTA curves
(Fig. 1). The dried precursor was calcined in air at 400, 500, 600,
700 and 800 C for 2 h to obtain nanocrystalline HAp powders.
Ph