The invention provides a preparation method of 
silicon dioxide / 
octacalcium phosphate particles capable of releasing 
methylthionine chloride monomers. The preparation method of 
silicon dioxide / 
octacalcium phosphate particles capable of releasing the 
methylthionine chloride monomers comprises the following steps: sequentially adding 
ammonium hydroxide, 
methylthionine chloride, tetraethoxysilane and a 
silane coupling agent into a solution containing water and ethyl 
alcohol, then stirring for 4 hours, centrifuging and washing the solution, then preparing the solution into a 
silicon dioxide 
colloidal solution containing methylthionine 
chloride by ethyl 
alcohol; then adding 
citric acid, 
calcium nitrate and diammonium 
hydrogen phosphate into the solution containing water and ethyl 
alcohol, adjusting pH value of the solution to 9 by 
ammonia water, subsequently adding 
polyethylene glycol and stirring for one hour, pouring the 
silicon dioxide colloidal solution containing methylthionine 
chloride into the solution, stirring for 3 hours, centrifuging, washing and 
drying the solution to obtain the 
silicon dioxide / 
octacalcium phosphate particles capable of releasing the methylthionine 
chloride monomers. The method is simple in process and low in costs of raw materials; the industrial production is easy to be implemented; the particles prepared by the method have good compatibility and are easy to be degraded; the methylthionine chloride is released from the particles in the form of 
monomer molecules into the solution; meanwhile, the releasing behavior is convenient to control.