Preparation of Calcium Phosphate-Biodegradable Polymer Composites with Ion-Releasing Ability for Enhancing Bone Formation

抄録

An inorganic-organic composite material, consisting of bioresorbable β-tricalcium phosphate (β-TCP) and a biodegradable polymer, is one of the most important materials for use in artificial bone with good shapability. In this work, to activate bone-forming cells immediately after being implanted in a living body, the ability to release therapeutic ions, such as Ca²⁺, Mg²⁺, and silicate ions was incorporated in the composite material. A small amount (8 vol%) of 46.1 SiO₂·24.4 Na₂O/MgO·26.9 CaO·2.6 P₂O₅ (mol%) glass particles was embedded successfully into the composite material. When the glass particles containing Na₂O were included in the material, the molecular weight of the polymer in the matrix phase was severely reduced and its hydrolysis in Tris-HCl buffer solution was drastically accelerated. On the other hand, when the glass particles containing MgO were included, therapeutic ions were continuously released with almost no change in the buffer solution pH. The released amount of silicate ions was well controlled, to avoid excessive dissolution, compared to those of Ca²⁺ and Mg²⁺ ions. Therefore, the glass particle is one of the most promising candidates to be a source in the composite for releasing therapeutic ions that enhance bone formation.

 

This Paper was Originally Published in Japanese in J. Jpn. Soc. Powder Powder Metallurgy 67 (2020) 278–283.