Effect of Potassium and Magnesium Doping on Sintering and Properties of Calcium Polyphosphate

• Main Author: Abbarin, Nastaran
• Other Authors: Grynpas, Marc D.
• Language: en_ca
• Published: 2011
• Subjects: calcium polyphosphate; CPP; doping; magnesium; potassium; degradation; 0794; 0541
• Online Access: http://hdl.handle.net/1807/29460

Porous constructs of calcium polyphosphate (CPP) are under investigation as a substrate for tissue engineering of cartilage for repair of osteochondral defects. Previous studies have shown that CPP has the required features to satisfy these requirements. However, its degradation rate is lower than desired. This study investigated the effect of doping with MgCO3, MgCl2, K2CO3 or KCl at a molar ratio of M/Ca = 0.02 on sintering and in vitro degradation behavior of CPP. Doping with magnesium or potassium improved the tensile and compressive strengths of CPP at similar porosities. After 15 days of aging in phosphate buffer saline, the rate of tensile strength loss was faster for the doped CPP groups than undoped CPP. The chemical degradation rate of Mg-doped CPP groups was the fastest among CPP groups. The chemical degradation rate of K-doped CPP groups was slower than undoped CPP.