New method for adsorbing the pharmaceuticals on mesoporous silica: Adsorption behavior of ibuprofen on mesoporous silica via the sealed and heating method

Many active pharmaceutical ingredients (APIs) currently being developed are poorly soluble in water, which enhances their solubility and bioavailability critical challenges. The evaporation/condensation (EV) method, wherein crystalline APIs are dissolved in organic solvents and adsorbed onto porous materials, is used to improve the solubility of APIs. However, the use of residual organic solvents during evaporation is challenging. Recently, the sealed heating (SH) method, in which a mixture of porous materials and a sublimated API is heated in a sealed container, has been reported as an alternative to the EV method. This study focuses on mesoporous silica (MPS-4R or -2R) as a porous material. The SH method was used to investigate the adsorption of ibuprofen (IBU) on MPSs. In the PXRD study, the IBU crystals were amorphized using the SH method. The elution rate of SH mixture containing 10 wt% IBU was approximately 2.7 times higher than that of the IBU crystals at 10 min after the start of the test. Based on these results, the SH method is a novel approach for amorphizing and enhancing the solubility of poorly water-soluble drugs without the use of organic solvents.