Synthesis of porous hydroxyapatite nano particles via sol-gel route by using different organic polymers

Due to superior properties, in recent years porous nano particles of hydroxyapatite are widely used in drug delivery and bone tissue engineering. In this study, porous nanoparticles of hydroxyapatite were synthesized via sol gel method by using organic polymers of gelatin, synthetic chitosan and the natural chitosan from shrimp shell. Structural and microstructural analyses were performed with X-ray diffraction (XRD) and scanning electron microscopy (SEM & FESEM). The surface area and pore size distribution were measured with BET method and the results were reported from the BJH and adsorption/desorption plots. The bioactivity of the samples was evaluated by immersing the samples in SBF solution. The FE-SEM results showed that the synthesized hydroxyapatite nano powders were agglomerates with the average particle size of 10-25 nm. BET results showed that hydroxyapatite nano particles were mainly mesoporous and gelatin addition resulted in finer particles and smaller pores with a narrow size distribution. Additionally, after immersing the samples in SBF solution, the weight differences and the SEM images showed that the hydroxyapatite samples which were synthesized by adding gelatin had higher bioactivity and more uniform apatite powders were deposited on this sample.