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 func-tions, 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 ma-terials for bone repair. Moreover, our strategy of improving stability is also of universal significance to other MOF materials.

Automated summary

The core-shell structure of Mg-MOF-74@MSiO2 was successfully synthesized using the sol-gel method, with the shell mainly composed of mesoporous silica. Under the protection of the mesoporous silica shell, the release rate of Mg2+ from Mg-MOF-74 in a simulated physiological environment was slowed down, leading to improved stability. The cytotoxicity analysis showed that Mg-MOF-74@MSiO2 had no cytotoxic effects and even had a better effect on promoting BMSCs cell proliferation compared to Mg-MOF-74. Therefore, Mg-MOF-74@MSiO2 has great potential for use in scaffold materials for bone repair, and the strategy used to improve stability is also universally significant for other MOF materials.