Matthias Rossmann

Analysis of Mechanisms for PVP-Active-Agent Formulation as in Supercritical Antisolvent Spray Process

Supercritical antisolvent technology can precipitate polyvinylpyrrolidone (PVP) particles and crystallize paracetamol (PCM) crystals first separately and then together in the form of a solid dispersion. Supercritical carbon dioxide (scCO2) is used as an antisolvent. For PVP particle generation, ethanol, acetone, and mixtures of ethanol and acetone are used as solvents. The initial concentration of PVP in the solution was varied between 0.5 and 5 wt%, the operation pressure between 10 and 30 MPa, and the composition of ethanol/acetone solvent mixtures between 100 and 0 wt% of ethanol at a constant temperature of 313 K. An increase in the content of the “poor” solvent acetone in the initial solution leads to a significant decrease in mean particle size. Fully amorphous PVP powder always precipitates for all the parameters investigated.