Application of ultrasonics for nanosizing drugs and drug formulations

Ultrasonication (US) is a modern technology that is routinely applied for a variety of laboratory tasks, from cleaning contaminants inside pores and cracks, to dispersion of solids, particle size reduction, emulsification, chemical reactions, and even cell disruption. It is fast, clean, affordable, and safe, requires minimal space and can be operated as a batch or a continuous process. In the last few decades, a number of articles have been published reporting the use of US as a single method or in combination with others for the nanosizing drug formulations aiming at solubility and permeability improvement. In this review, the different application modes and the principles of operation of the relevant apparatuses are presented. The effects of processing parameters on the efficiency of the method are described in association with the characteristics of the sonicated dispersion. In the last sections, the application of US in the pharmaceutical field is demonstrated by many examples which prove its capability to assist with bioavailability and therapeutic problems by presenting the drugs as nanosized formulations for different routes of administration.