Preparation and Characterization of Calcium-based Biomaterials

Scallop shell powders were heated at 1450 °C for 4 h, then ground using a dry super grinder (Nano Jetmizer NJ-300-D, Aishin Nano Technologies Co. Ltd., Saitama, Japan), followed by cooling in a vacuum chamber. This provided BiSCaO with dry powder diameters of 3–9 (average 6 μm) and was purchased from Plus Lab Corp., Kanagawa, Japan. According to the manufacturer, the content of CaO in this BiSCaO preparation was 99.6%. BiSCa(OH)₂ was obtained from Scallow, Kohkin Inst. Co. Ltd., Tochigi, Japan, had a dry powder diameter of 10–100 μm (average 46 μm), and the CaO and Ca(OH)₂ concentrations were <5% and >90%, respectively. Sodium polyphosphate (Na-polyPO₄; PP), sodium triphosphate (Na-triPO₄; TP), 0.4 w/v% trypan blue solution, and 1 N HCl were purchased from FUJI FILM Wako Pure Chemical Corp., Osaka, Japan. Chondroitin sulfate and heparin were purchased from SEIKAGAKU Corp., Tokyo, Japan. Non-anticoagulant heparin carrying polystyrene (NAC-HCPS) [18 (link),19 (link)] and low-molecular-weight heparin/protamine nanoparticles (LMWH/P NPs) [20 (link),21 (link)] were prepared as previously described.