Calcium Phosphate Compounds Doped with Magnesium, Strontium and Barium Ions to Enhance Osseointegration of Bone Implants

A method for creating bioactive coatings for implants is proposed. These coatings consist of a plasma-coated hydroxyapatite layer and a dicalcium phosphate dihydrate transition layer deposited on top. This layer is then hydrolyzed to produce octacalcium phosphate (where Me = Mg2+, Sr2+, Ba2+) doped with divalent metal ions. X-ray diffraction analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy revealed that strontium cations isomorphically replace calcium in the octacalcium phosphate structure, while magnesium and barium ions inhibit the phase transformation of dicalcium phosphate dihydrate into octacalcium phosphate, forming amorphous phases. An in vitro study in a simulated physiological environment of SBF demonstrated the ability of coatings based on octacalcium phosphate doped with magnesium, barium and strontium cations to biomineralize, indicating their increased bioactive potential compared to bioinert hydroxyapatite.