the paper is focused on the formation of hydroxyapatite nanoparticles (hap) in polyelectrolyte-modified microemulsions, in a microemulsion template phase consisting of cyclohexane, water, cationic surfactant and cosurfactant, in the presence of na-polyacrylate (paa) as an anionic polyelectrolyte. it is shown that paa, can be incorporated into the individual inverse microemulsion droplets. the m...