Evaluation of drug loading onto MCM-48 via supercritical CO2 deposition: Effects of drug type, temperature, and silica structure

Mesoporous silica is a promising drug delivery carrier owing to its high surface area, tunable pores, and ability to stabilize amorphous drugs. In this study, supercritical fluid deposition (SCFD) using supercritical CO 2 (15 MPa) was employed to load ibuprofen and ketoprofen into MCM-48 mesoporous silica. The effects of drug type, temperature (313 K to 333 K), and silica framework were evaluated systematically. Transmission electron microscopy (TEM) and nitrogen adsorption confirmed that the three-dimensional cubic mesostructure of MCM-48 remained intact after impregnation. Fourier-transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA) verified the successful incorporation, with distinct thermal events indicating external and pore-confined adsorption. Ibuprofen consistently achieved higher loading than ketoprofen, driven by its greater solubility in supercritical CO 2 , indicating that solubility is the dominant factor over surface affinity. Temperature had only a modest influence owing to the opposing effects of decreased CO 2 density and reduced competitive CO 2 adsorption at higher temperatures. Compared with SBA-15, MCM-48 exhibited superior uptake across all conditions, which was attributed to its larger surface area and interconnected pore network. These results demonstrate that SCFD enables the efficient, solvent-free incorporation of active compounds while preserving mesostructural integrity, offering guidance for the design of high-performance mesoporous carriers in pharmaceutical and related applications. • Supercritical CO 2 deposition (SCFD) of ibuprofen and ketoprofen into MCM-48 • Preservation of mesoporous structure of MCM-48 after SCFD treatment • Higher loading efficiency of ibuprofen than ketoprofen due to greater CO 2 solubility • Moderate influence of temperature changes on drug loading in the SCFD process • Superior drug uptake of MCM-48 over SBA-15 due to high surface area and pore volume