Calcium chloride cacl2

Stoichiometric hydroxyapatite (Ca₁₀(PO₄)₆(OH)₂, Ca/P = 1.68, ST-HAP) and Ca-deficient hydroxyapatite (Ca_10−x(HPO₄)_x(PO₄)_6−x(OH)_2−x, Ca/P = 1.38, DEF-HAP) were supplied by Taihei Chemical Industrial Co., Ltd., Japan. ST-HAP was synthesized by mixing calcium hydroxide and phosphoric acid solutions^{40 , 41} . The precipitate was dried at 100 °C. DEF-HAP was synthesized by mixing slurries of calcium hydrogen phosphate dihydrate with an aqueous solution of sodium hydroxide^{31 (link), 41} . The precipitate was dried at 150 °C. Strontium chloride (SrCl₂), magnesium chloride (MgCl₂), and calcium chloride (CaCl₂) were purchased from Wako Pure Chemical Industries Co., Ltd., Japan. Sr standard solutions (1 mg/mL) for ICP-MS (PerkinElmer Japan Co., Ltd., United States) were also purchased from Wako Pure Chemical Industries. All materials were used without further purification.

PHBH (3HH = 10.6 mol%) was provided by Kaneka (Tokyo, Japan); sodium alginate (500 cps) was obtained from Nacalai Tesque (Kyoto, Japan); chloroform (CHCl₃) and calcium chloride (CaCl₂) were obtained from FUJIFILM Wako Pure Chemical (Osaka, Japan); EDTA was obtained from Thermo Fisher Scientific (Waltham, MA, USA). All other chemicals and reagents were of analytical grade and were used without further purification.