(394e) Recrystallization of Pharmaceutical Drug Particles Using Supercritical Fluid

In this research, recrystallization of adefovir dipivoxil particle was carried out by rapid expansion of supercritical solutions (RESS) process, one of the well-known supercritical processes. Supercritical carbon dioxide, a green solvent, was selected as a solvent. The effect of process parameters such as extraction temperature and pressure, pre-expansion temperature, spray distance, and nozzle configuration on the particles size of adefovir dipivoxil were evaluated and found that the process parameters influenced the particles size. Increasing the extraction temperature (308.15-328.15K) caused the particle size increasing of adefovir dipivoxil. The particle size decreased with increasing extraction pressure (20-30MPa). The particle size of adefovir dipivoxil was increased with increasing pre-expansion temperature. An increase in the spray distance (8-32cm) resulted in a decrease in the average particle sizes. The effect of the nozzle internal diameter on the size and shape of the precipitated particles was examined different nozzle internal diameters (152-762μm). When the nozzle internal diameter size was bigger, the particle size did not show significant change. Processed adefovir dipivoxil particles by RESS process were analyzed by SEM, XRD, DSC and FT-IR spectra.