Hydroxyapatite coated poly(lactic acid) microparticles with copper ion doping prepared via the Pickering emulsion route

This work aimed to integrate the ionic substitution feature of hydroxyapatite nanoparticles (HAps) on poly(lactic acid) (PLA) surfaces. HAp-coated PLA microparticles were prepared through the Pickering emulsion route. HAps with adequate surface charge and aggregate size were prepared in a 0.1-M salt dispersion in order to induce oil-water interfacial adsorption of HAps in a Pickering emulsion. A batch sorption process was conducted to evaluate the potential of HAp-coated PLA microparticles to be loaded with copper ions. The concentration of Cu2+ in the supernatant phase was measured by atomic adsorption spectroscopy and their adsorption capacity was determined. The copper ion (Cu2+) adsorption capacity of the microparticles increased with (a) the quantity of HAps adsorbed (consistently increased with HAp solid content) and (b) higher initial Cu2+ concentration of the doping medium. In conclusion, HAp-coated PLA microparticles with the ion doping feature were successfully prepared through the Pickering emulsion route.