Fabrication of novel bone haemostasis sheet by using sugar-containing hydroxyapatite and plant-derived polymer

The fabrication conditions of bone-haemostasis sheet were examined by using (i) phosphoryl oligosaccharides of calcium (POs-Ca), sugar-containing hydroxyapatite (s-Ca₁₀(PO₄)₆(OH)₂: s-HAp) derived from POs-Ca and (ii) natural plant-derived polymers (locust bean gum (LBG), guar gum (GG) and alginate (AG)). The sol, which had been prepared by dissolving 2 mass% LBG/GG and 2 mass% AG into 200 cm³ deionized water and then by agitating at the speed of 20 000 r.p.m., was immersed into 3 mass% POs-Ca solution at room temperature for 24 h; it was hydrothermally treated at 100°C for 5 h, and then freeze-dried at -50°C for 24 h to form porous composite sheet. The microscopic observation showed that the pore sizes were controlled in the range of 5-100 µm by the optimization of LBG/GG ratio. The composite sheet showed the noted uptake of simulated body fluid (1426%) at 37.0°C and also the human blood. Thus, the porous composite sheet was found to be a promising candidate of the bone haemostasis, on the basis of the data of haemostasis, uptake ability of SBF and solubility in acetic acid-sodium acetate buffer solution.