Physicochemical properties and in vitro activity of SrHPO₄ modified magnesium oxychloride bone cement

Abstract In response to the shortcomings of magnesium oxychloride cement (MOC), which has excellent with outstanding mechanical properties and favorable bioactivity but poor water resistance, strontium hydrogen phosphate (SrHPO 4 ) was used as a water resistance modifier for MOC in the paper, and the effects of SrHPO 4 on the strength, water resistance, in vitro degradation and bioactivity of MOC were investigated; the results showed that SrHPO 4 could enhance the water resistance of MOC, in which the initial strength of MOC containing 4.0 wt% SrHPO 4 was 92.3 ± 2.5 MPa, and the strength was still 8.2 ± 0.9 MPa after 84 d of immersion in SBF solution; the degradation experiments of the samples in SBF solution showed that the degradation of SrHPO 4 -MOC was controlled, and the low alkaline environment created by the degradation promoted the deposition of hydroxyapatite on the cement surface, it indicated that SrHPO 4 -MOC material had good degradation properties and bioactivity; cell experiments showed that compared with MOC, SrHPO 4 -MOC was noncytotoxic and could promote cell proliferation, which was expected to be a new material for bone repair.