Method for preparation of the supersaturated solution of calcium phosphate and the thin film of calcium phosphate crystal by using the solution

A method for preparation of the thin film of calcium phosphate crystal by coating the supersaturated solution of calcium phosphate to a solid surface, comprising the steps of:

• 1) preparing a solution of calcium and phosphate ions by dissolving calcium phosphate crystals or salts of calcium and of phosphate in acidic solution (step 1);
• 2) mixing the acidic solution of calcium and phosphate ions of the step 1 with alkaline solution at a temperature, wherein the temperature of the acidic solution and of the alkaline solution and the reaction temperature of step 2 are 0-37° C. (step 2);
• 3) excluding amorphous calcium phosphate particles or crystals can act as nuclei for nucleation and growth of crystals, which from the solution prepared in step 2, to inhibit further nucleation reaction and growth of crystals in solution (step 3) to produce a supersaturated solution of calcium phosphate;
• and
• 4) coating the supersaturated solution of calcium phosphate produced in step 3 to a solid surface at a temperature of 0-60° C.