Synthesis of polycaprolactone/nano hydroxyapatite microspheres

Polycaprolactone(PCL)/nano hydroxyapatite(nHA) microspheres are advantageous material for manufacturing tridimensional scaffolds and formulating drug delivery systems for bone regeneration. The work was aimed to study the effect of processing variables on the properties of PCL/nHA microspheres. nHA was produced by precipitation method and was obtained calcium deficient nanoparticles consisted of nanorods (∼47 nm x ∼8 nm), according to the results of XRD, FTIR and TEM. PCL/nHA microspheres was produced by solid-in-oil-in-water emulsion solvent evaporation method. The variables studied were concentration of PCL (5,7.5 and 10 % w/v), nHA addition (17, 23 and 28.5% m/m) and surface treatment of nHA with stearic acid (AE). PCL/nHA microspheres were characterized by XRD, FTIR, SEM and TGA. The best result was obtained with a PCL concentration of 10% (w/v) and 23 % (m/m) of modified nHA. Solid PCL/nHA particles ranging 30-70 μm and containing 14 % of nHA dispersed in the polymer matrix were obtained, with agglomerates of nHA raging 5 -15 μm. These results suggest the promising use of this material in bone regeneration devices. (author)