Abstract
Co-substituted hydroxyapatite (HAP) with cationic rubidium (Rb+) and anionic selenite (SeO32-) was synthesized at different contributions of Rb+ ions. The chemical formula of the composition is [RbxCa(10-0.5x)(PO4)(5)(SeO3)(OH)(2)], where 0 <= x <= 0.8 with step 0.2. The structure and morphology of the as-prepared compositions were investigated upon the concentration of (Rb+) ions. It was mentioned that the roughness average (R-a) starts from 26.2 nm and grows up, reaching 42.6 nm. This noticeable roughness degree due to Rb insertions is reflected in adhesive ability in the biological environment. Rubidium dopant has a significant effect on particle size that inhibits size growth. The internal porosity could be classified as micropores except at x = 0.6 and 0.8, which are considered macro-pores. Rb/Se-HAP compositions' cell viability was investigated through the human osteoblast cell line (HFB4), and the life ratio achieved around 98.1 +/- 3.9%. Furthermore, the additional Rb+ ions promote antibacterial activity, whereas the inhibition zone started from 1.6 +/- 0.2 and 1.3 +/- 0.3 mm and grew up to 5.3 +/- 0.9 and 4.9 +/- 0.8 mm for x = 0.0 and 0.8, against E. coli and S. aureus, respectively. Thus, the reported stoichiometric compositions are considered to be promising materials for biomedical applications.