Preparation and properties of proteinaceous microspheres made sonochemically

In 1990, Suslick and co-workers developed a method in which they used high-intensity ultrasound to make aqueous suspensions of proteinaceous microcapsules filled with water-insoluble liquids, and demonstrated the chemical mechanism of their formation.^[1] Suslick's paper opened up a new field that is reviewed in the current manuscript, and this article will attempt to review the experiments that have been conducted since the discovery of this phenomenon. It will answer questions regarding the mechanism of the formation of the microspheres, whether the sonication denaturates the protein or if its biological activity is maintained, and, finally, will address possible applications of the proteinaceous microspheres. Proteinaceous microbubbles will be referred to as proteinaceous microspheres (PM) throughout this review, although they may not have a perfect spherical shape in all cases. This review will start with a short introduction to sonochemistry, although this topic is, and has been reviewed frequently.^[2-7] The review covers literature published until December 2006.