(381f) Sonoseeding: An Alternative Approach for Scale-up of Batch Sonocrystallization

Kiran A. Ramisetty, V Kannuchamy, Åke C. Rasmuson*

Department of Chemical and Environmental Science, Synthesis and Solid State Pharmaceutical

Centre (SSPC), Bernal Institute, University of Limerick, Limerick, Ireland.

This work demonstrates the strategic way of controlling the product crystal size distribution using two-reactor system of generating seed crystals with ultrasound followed by growth. A saturated solution of Form III Piracetam at 50^oC in isopropanol was prepared in a 50ml crystallizer and preheated to 55 ^oC to ensure complete dissolution. This prepared solution was cooled down to its MSZW (Meta stable zone width) at 35^oC and subjected to ultrasonication induce nucleation. Wet seed suspension loaded into crystallizer with 10times larger volume than seed generator to grow crystal for better yield. Initially growth experiments conducted isothermally for concentration to reach equilibrium and followed by a slow cooling profile. A constant FBRM count number confirmed the negligible amount of secondary nucleation during the growth phase. Temperature the crystallizer maintained same as the temperature in the seed generator. Sonication mode, time and operating temperature are effecting parameters in producing uniform seed size distribution. Scale-up studies proved the capability of this technique in delivering narrower product crystal size distribution.