Synthesis of functionally graded MgCO₃ apatite accelerating osteoblast adhesion

Abstract

As a means of improving the biological properties of materials for use as bone substitutes, functionally graded carbonate apatite containing Mg, FGMgCO3Ap, was synthesized at 60 degrees C and pH 7.4 using a gradient magnesium supply system. X-ray diffraction analysis of FGMgCO3Ap showed a poorly crystallized apatitic pattern, similar to that of human bone. ESCA analysis clearly showed the negative gradient distribution in Mg1s intensity (atomic concentration) of magnesium from the crystal surface toward the inner core. When the FGMgCO3Ap crystals were mixed with collagen, the resulting FGMgCO3Ap-collagen composite, irradiated with UV light for 4 h, retained their features in the saline solution. After washing away the nonadhesive cells, a cell adhesion assay showed that the optical density of the FGMgCO3Ap-collagen composite was higher than that of the CO3Ap-collagen composite. SEM observation showed that the osteoblast-like cells adhered well to the surface of the FGMgCO3Ap-collagen composite. Staining with hematoxylin-eosin and alizarin red confirmed the existence of a great many more cells and a thicker extracellular matrix layer on the FGMgCO3Ap-collagen composite than on the CO3Ap-collagen composite. This result demonstrated the acceleration effect of magnesium ions on osteoblast adhesion on the FGMgCO3Ap-collagen composite.

Biocompatibility and bioactivity of porous polymer-derived Ca-Mg silicate ceramics

“…that Mg is a promising agent in skeletal tissue engineering applications due to its ability to 16 stimulate new bone formation [23]. Mg was suggested to interact with integrins of osteoblasts 17 that are responsible for cell adhesion and stability [23,50]. The importance of Mg in bone [25,51,52].…”

Fabrication and biological evaluation of hydroxyapatite ceramics including bone minerals

“…As for Na substitution, Jung et al 17) added sodium nitrate to calcium hydroxide and phosphoric acid to cause a reaction, and as for K substitution, Kannan et al 18) reported K-substitution of HAp by a wet method using potassium nitrate. Li et al 19) reported simultaneous substitution of Na + and CO 3 2¹ ions, and Yamasaki et al 20) reported simultaneous substitution of Mg 2+ and CO 3 2¹ ions. There have been only a few reports, however, in which three or more types of ions have been substituted simultaneously.…”

Creation of highly functional CO3Ap-collagen scaffold biomaterials

“…Mg 2+ ions may contribute to the bone metabolism of osteoclast and osteoblast action with the integrins at Recently, scaffold biomaterials have been studied in the tissue engineering field. In a continuation of those studies, functionally graded CO3apatite containing Mg, producing a negative gradient of magnesium concentration from the surface toward the core, was synthesized 12) . The degree of cell adhesion to a composite that was made by mixing the FGMgCO3apatite and collagen to facilitate bonding and processing was investigated.…”