Small Titanium-Based MOFs Prepared with the Introduction of Tetraethyl Orthosilicate and Their Potential for Use in Drug Delivery

Metal-organic frameworks (MOFs) have attracted much attention in the areas of biomedicine and medicine owing to their versatile porous structure. However, the oversize and high cellular toxicity of some metal-based MOF particles have hindered their development. Therefore, a series of small Ti-based MOFs are prepared with the introduction of tetraethyl orthosilicate (TEOS) into the reaction system. Compared with the Ti-based MOFs prepared by traditional methods, the size of the Ti-based MOFs prepared with this method is decreased by 42.78%. Meanwhile, the good biocompatibility of the prepared Ti-based MOF particles toward the L929 cell lines is proven using CCK-8 assays. Furthermore, the controlled release property of the Ti-based MOFs is evaluated by using ibuprofen (IBU) as a model drug. The amount of drug loaded in the samples is shown to be approximately 10%, and approximately 95% of the IBU is released from the MOFs after exposure to PBS for 24 h. We conclude that the size-decreased Ti-based MOFs prepared with the introduction of TEOS into the reaction systems are potential drug carriers in terms of their good biocompatibility and effective performance in the controlled release of a drug.