Study on the degradation of hydroxypropyl methylcellulose-modified magnesium phosphate cement in different solutions

Magnesium phosphate bone cement (MPBC) is a bone repair material that has been extensively studied. For better availability of clinical medicine, its degradation rate needs to be effectively controlled. Hydroxypropyl methylcellulose (HPMC) has often been used as a drug carrier for controlled drug release. This property was utilized to influence the release kinetics of MPBC. This work investigated the degradation mechanism of MPBC controlled by HPMC. It was found that MPBC samples with 3 wt. % HPMC had the optimal properties. In this case, the setting time was 11 min and the maximum strength was 63.9 ± 2.5 MPa. The study found HPMC primarily controlled the degradation of MPBC hydration products via the combined actions of gradual diffusion, and release of MPBC hydration products, which subsequently caused the swelling, corrosion, and dissolution of the HPMC skeleton. Besides, the results showed that HPMC-modified MPBC has good bioactivity, which is beneficial to bone repair. This bioactive HPMC-modified MPBC showed a controllable degradation rate and proper mechanic properties, which may be applied to bone repair.