1 The Power of Ultrasound

During the last 20 years we have witnessed an amazing increase in the application of ultrasonic energy in different fields of science. This is especially true for analytical chemistry. The number ofmanuscripts devoted to almost all kinds of analysis dealing with the uses of ultrasonic energy continues to grow year by year. As the uses of ultrasonication have become increasingly important in analytical chemistry so to has the importance of the type of ultrasonic device chosen to work with. Figure 1.1 shows themost commonultrasonic devices usednowadays in analytical applications.Not all devices perform equally and neither are all intended for the same applications. Therefore, thefirst thing to acquirewhendeveloping analytical chemistrywith the aid of ultrasonication is a knowledge of the differences among the ultrasonic apparatus available, especially of the advantages and disadvantages expected for each one. Therefore, this chapter explains the state-of-the-art of ultrasonic technology as applied to analytical chemistry.