Principles and application of ultrasound in pharmaceutical powder compression

The use of ultrasound during the tableting of pharmaceutical powders is a n ew concept. However, in the metallurgy, plastic, acid ceramic industries, u ltrasound-assisted compression of materials has been known fur some years. Ultrasound improves the characteristics of the compression process leading to optimized mechanical strength of the compacts without applying excessive compression force. Therefore, problems associated with high-pressure compr ession in tableting can be overcome and tablets may be manufactured more ec onomically acid consistently with the aid of ultrasound compared to convent ional pressure processes. Although great progress in the theoretical unders tanding of the ultrasound-assisted powder compression process has been made since the late 1960s, the need For further research in the area of ultraso und application during pharmaceutical powder compression is essential. Furt her investigations on a wide range of drugs and excipients, to expand the u sefulness and scope of the ultrasound-assisted technique, and to understand the complex phenomena involved in the process, are needed. In this article the principles, advantages, and limitations of the application of ultrason ic vibrations during pharmaceutical powder compression is reviewed with the hope that this article can contribute to, and stimulate research in the ar ea.