(659c) Precipitation of Ultra-Fine Particles of Fenofibrate with Controlled Size Distribution by Resolv: Rapid Expansion Vs Stabilizer Concentrations

Supercritical fluids (SCF) are increasingly being looked at as green solvents to precipitate fine particles of variety of chemicals ranging from pharmaceuticals to explosives. While there are different SCF processes are available, Rapid Expansion of Supercritical Solutions in SOLVent (RESOLV) in particular, offers an attractive alternative to conventional precipitation processes as it avoids the use of organic solvents and aqueous suspension of fine particles is readily obtained. Despite of extensive literature available on particle formation using RESS/RESOLV, mechanism of RESS is poorly understood. It is widely accepted that rapid expansion of supercritical solutions is necessary to attain high levels of supersaturations and precipitate ultrafine particles. However, growth and agglomeration of particles after precipitation also controls the particle size and its distribution. Use of water as a solvent for collection of particles allows one to use stabilizers such as surfactants and water loving polymers to stabilize the particle size and size distribution. This work aims to develop the complete understanding of the mechanism of RESOLV. Attempts are made to quantify the effect of rapid expansion and the stabilizer concentrations and to identify the controlling parameter so as to be able to tailor the desired particle size and distribution by RESOLV.