Experimental checking of USASD mechanisms

As previously stated, the principle behind USASD Is based on the mechanical effects of US, which enhance the kinetics of some processes. Let us review such effects In the light of recent studies. 

That soft digestion enhanced by US was first demonstrated by Kannan and Pathan [15], who soft-digested aqueous benzoic add In the experimental device shown in Fig. 3.3. The cylindrical geometry for the sample was intended to ensure uniformity in the solid surface and improved accessibility by the liquid phase. The solid was immersed in a water bath with temperature control at 31 °C. The ultrasonic source was a probe that was inserted vertically into the water bath. The device was rated at 500 W and 20 kHz frequency. Trial experiments of USASD without temperature control of the water bath 

C — concentration Dq — initial particle size SAq — initial surface area. Reproduced with penaission of Elsevier, Ref. [16]. 

Ultrasound-assisted soft digestion (USASD) has been applied to a variety of sample and analyte types in widely diverse fields. This section discusses its implementation in the analytical process and its principal uses. Ultrasonic soft digestion has been used in connection with both organic and inorganic analytes. 

Ultrasound-assisted soft digestion has been used for other practical purposes from which analytical chemists can derive new applications. One case in point is in medicine, where ultrasound has been used as an adjunctive therapeutic treatment for clot dissolution of pharmacological thrombolysis. The combination of externally applied low-frequency high-intensity US with fibrinolytic therapy resulted in more rapid and complete reperfusion than the application of US or administration of fibrinolytic agents alone [42]. 

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