PVP Addition during Hydroxyapatite Synthesis: Effect on Albumin Adsorption
Hydroxyapatite nanoparticles were synthesized by preparing an aqueous solution comprising 0.5M Ca(OH)2, 0.3M H3PO4 and 1M CH3CHCO2HOH (lactic acid) at pH of 3.7. KOH was added to the solution until pH=12 was reached, to precipitate hydroxyapatite. The incubation time ranged from 24 to 88 hours and the precipitates were then filtered on filter paper with the aid of a vacuum pump. The powders were synthesized with and without PVP addition. The powders were then sintered at 1100°C. Sintered and non sintered powders were characterized by scanning electron microscopy with field emission gun (FEG-SEM) and transmission electron microscopy (TEM) in order to assess particles morphology. Structural characterization was performed by X-ray diffractometry with Rietveld refinement. Albumin adsorption experiments were carried out on the powders with the aid of UV-VIS spectrometry. The results showed that the samples produced in the presence of PVP showed smaller particles when compared to non-dispersed samples. Albumin adsorption was more effective on the powders synthesized with dispersant.