High-Resolution Ultrasonic Spectroscopy for Crystallization Process

High-Resolution Ultrasonic Spectroscopy (HRUS) is a novel analytical technique for non-destructive material analysis for a wide range of samples and processes. This technique is based on precision measurements of velocity and attenuation of acoustical waves at high frequencies propagating through materials. It has considerable advantages over many alternative technologies because it can be applied to systems that are optically opaque and concentrated without the need of any sample preparation. It provides an unprecedented range of new analytical capabilities for research, product development, quality and process control. Applications of this technique include analysis of solution-phase crystallization, aggregation and gelation phenomena, particle sizing, stability of emulsions and suspensions, microstructural transitions and pharmaceutical manufacturing. Here, we review the theory of the HRUS and its applications on crystallization process.