Ultrasound, Surfactants and Polymers: Curtailing Particle Size and Distribution by Liquid Antisolvent Precipitation
Sameer Dalvi, Chemical Engineering, New Jersey Institute of Technology, 138 Warren Street, YCEES 222, Newark, NJ 07102, Rajesh Dave, New Jersey Center for Engineered Particulates, New Jersey Institute of Technology, 138 Warren Street, YCEES 208, Newark, NJ 07102, and Somenath Mitra, Department of Chemistry and Environmental Science, New Jersey Institute of Technology, 323 King Blvd., Newark, NJ 07102-1982.
Precipitation of ultra-fine particles of antifungal agent Griseofulvin from its organic solution in acetone has been attempted using water as liquid antisolvent. Ultrasound and high jet velocities are used to achieve enhanced micromixing of organic solution and antisolvent. Polymers and surfactants have been used to decelerate the growth of the particles by coagulation and condensation. It is shown that fine submicron particles can be precipitated by lowering the mixing time below the precipitation time by enhanced micro-mixing and/or increasing the precipitation time above the mixing time by increasing viscosity and decreasing interfacial surface energies (and thereby controlling the Ostwald ripening) with the use of polymer and surfactants