Impregnation of non-steroidal anti-inflammatory drugs (ibuprofen and ketoprofen) onto mesoporous silica SBA-15 using supercritical CO2

Abstract

Ibuprofen and ketoprofen were impregnated onto SBA-15 type mesoporous silica using the supercritical fluid deposition (SCFD) method with supercritical carbon dioxide (CO₂) as the solvent at temperatures ranging from 313 K to 343 K and a pressure of 15 MPa. The prepared samples were evaluated using electron microscopy, nitrogen adsorption measurements, infrared spectroscopy, and thermogravimetric analysis. The impregnation of the drugs into the mesoporous silica pores was confirmed by nitrogen adsorption experiments. The amount of drug impregnation was found to depend on both the drug species and the type of mesoporous silica. It was suggested that the solubility in supercritical CO₂ played a dominant role for the drug species. There was virtually no effect of temperature on the amount of drug impregnation, which may be attributed to the interplay between the solubility of supercritical CO₂ and the adsorption equilibrium of the drug on mesoporous silica under supercritical CO₂ conditions.