Amorphous strontium polyphosphate microparticles for treatment of osteoporosis and inducing bone cell mineralization

摘要

A method for the preparation of morphogenetically active amorphous strontium-polyphosphate nanoparticles or microparticles ("Sr-a-polyP-MP") comprises: (a) dissolving sodium polyphosphate in an aqueous medium, such as distilled water, and adjustment to about pH10 with a basic aqueous solution, such as sodium hydroxide; (b) dissolving of a strontium salt in a suitable aqueous medium, such as aqueous ethanol; (c) slow (e.g. dropwise) addition of the polyphosphate solution to the strontium salt solution, keeping the pH at about 10 with a basic aqueous solution, such as sodium hydroxide, (d) forming particles, preferably by stirring of the suspension overnight at room temperature; and (e) collecting the particles, preferably by filtration, and washing with an aqueous medium, e.g. aqueous ethanol, and drying. The strontium polyphosphate particles may be encapsulated into acid-resistant capsules for oral administration. The microparticles or nanoparticles may be embedded into microspheres of poly(D,L)-lactide-co-glycolide (PLGA). The strontium nanoparticles or microparticles may be used in a method of preventing or treating bone-related diseases such as osteoporosis, and also in bone repair.