Core-shell structure Mg-MOF-74@MSiO2 with mesoporous silica shell having efficiently sustained release ability of magnesium ions potential for bone repair application

To improve the stability of Mg-MOF-74 in physiological water environment and enhance its biomedical functions, XRD, FTIR, SEM-EDS, BET and TEM characterization confirmed that the core-shell structure of Mg-MOF-74@MSiO2 was successfully synthesized by sol-gel method, and the shell was mainly composed of mesoporous silica with a pore size of 2.0–2.5 nm and a thickness of about 40 nm. ICP-OES test showed that under the protection of mesoporous silica shell, the Mg2+ release rate in simulated physiological environment of Mg-MOF-74 slowed down, that is, the stability of Mg-MOF-74 was improved. Furthermore, the cytotoxicity analysis confirmed that Mg-MOF-74@MSiO2 had no cytotoxicity, and even showed better effect on promoting BMSCs cell proliferation than Mg-MOF-74. Therefore, Mg-MOF-74@MSiO2 has good application potential in scaffold materials for bone repair. Moreover, our strategy of improving stability is also of universal significance to other MOF materials.