Enhanced Release of Calcium Ions from Hydroxyapatite Nanoparticles with an Increase in Their Specific Surface Area

Synthetic calcium phosphates, e.g., hydroxyapatite (HAP) and tricalcium phosphate (TCP), are the most commonly used bone-graft materials due to their high chemical similarity natural hydroxyapatite—the inorganic component of bones. Calcium in form a free ion or bound complexes plays key role many biological functions, including bone regeneration. This paper explores possibility increasing Ca2+-ion release from HAP nanoparticles (NPs) by reducing size. Hydroxyapatite were obtained through microwave hydrothermal synthesis. Particles with specific surface area ranging 51 m2/g 240 sizes 39, 29, 19, 11, 10, 9 nm experiment. The structure nanomaterial was also studied means helium pycnometry, X-ray diffraction (XRD), transmission-electron microscopy (TEM). calcium-ion into phosphate-buffered saline (PBS) studied. highest Ca2+ ions, i.e., 18 mg/L, observed an average nanoparticle size nm. A significant increase areas 183 above, 11 below. No substantial dependence for larger particle sizes.