Facile, single-step process for the preparation of controlled release formulations of ibuprofen in a hydrophilic matrix using supercritical CO2

Abstract

A green, single-step process has been proposed to prepare a controlled-release formulation of a generally hydrophobic drug, ibuprofen (IBU), in polyethylene glycol (PEG), a hydrophilic excipient matrix. The method uses CO₂ in its supercritical state as the processing solvent. Supercritical CO₂ (scCO₂) is a highly diffusive medium and can liquefy PEG, assisting in the homogeneous mixing of the drug and the excipient. The scCO₂-processed IBU-PEG composite has been compared with the composite prepared using acetone, a conventional volatile organic solvent. The release profiles for the composites prepared using scCO₂ and acetone, respectively, are very similar, indicating that scCO₂ can be used as a replacement for acetone in this case. The pH dependence of drug release and the stability of the composite formed are also investigated.