(789f) Effect of Ultrasonic Irradiation On the Behavior of Primary Nucleation and Growth of Cloxacillin Benzathine

The effect of ultrasonic irradiation on the behavior of primary nucleation of cloxacillin benzathine in supersaturation solutions with different levels were studied in the present work. The solubility of cloxacillin benzathine in binary solvent mixtures of ethanol and water were measured by a dynamical method, using a medium-throughput multiple reactor (Crystal 16^™, Avantium, Netherlands). Based on the solubility data, the induction periods of this system were measured under different experiment conditions. Compared to the induction time without ultrasonic irradiation, the induction period for different supersaturations decreased with increasing ultrasonic irradiation energy and subsequently increased to a certain degree. Above this level of ultrasonic irradiation, the induction period decreased dramatically. Besides that, the composition of solution and feeding rate of the reactant were investigated to figure out the influential factors to the primary nucleation behaviors for this system. Measurements of crystal size and crystal habits for irradiated and silent experiments showed that the particle size and aggregates were both affected by ultrasonic irradiation and is highly correlated with the supersaturation. The products with desired crystal size could be obtained by optimally controlling the conditions of supersaturation and ultrasounic irradiation.