Ordered mesoporous magnesium silicate with uniform nanochannels as a drug delivery system: The effect of calcination temperature on drug delivery rate

Magnesium silicate nanostructured biomaterials with good bioactivity, biocompatibility, and mechanical properties are promising for applications in various biomedical fields. Herein, ordered mesoporous magnesium silicate (OMMS) was prepared by sol-gel method and the effect of calcination temperature to evaluate its application as ibuprofen (IBU) drug delivery system was investigated. The synthesized powders were calcined at 350, 550, 750 °C and characterized by X-ray diffraction (XRD), Fourier transmission infrared spectroscopy (FTIR), N2 adsorption-desorption, and transmission electron microscopy (TEM). All samples demonstrated mesoporous characteristics with high specific surface area ranging from 386 to 504 m2/g. It was found that the sample calcined at 350 °C showed the slowest drug release rate among all samples, which is due to smaller pore size and the existence of larger amounts of intrawall microporosity. Cytotoxicity of MG63 osteoblast cell line was investigated by MTT assay, indicating no toxicity for IBU- loaded sample calcined at 550 °C with a concentration less than 10 mg/ml. This study has revealed that altering the calcination temperature may change the drug delivery behavior of OMMS by influencing textural properties and suggests OMMS as a promising local drug delivery system in bone tissue engineering applications.