Analytical applications of ultrasound-assisted slurries

The use of ultrasound-assisted slurry is a simple, efficient alternative to circumvent problems associated to digestion of samples with complex matrices derived from the required hazardous conditions, but also to leaching when efficiencies are not quantitative. Applications involving slurries prepared by ultrasonic assistance are continuously proposed with different detection systems, which demonstrate the versatility of slurries for metallic elements determination. 

Ultrasound-assisted slurry formation followed by cold-vapour or hydride generation 

Ultrasonic slurry formation has been frequently used prior to cold-vapour and hydride generation. Both procedures usually involve a drastic treatment of the slurry to ensure complete transfer of the target species to the liquid phase for subsequent formation of the gas phase — after a normally long standing time — which is the only phase reaching the atomizer in the case of hydride generation and the detection point in the case of mercury vapour formation. The gaseous analytes or their hydrides are most often obtained in a commercial or laboratory-made dynamic flow injection manifold. 

Uitrasound-assisted siurry formation prior to its introduction into the atomizer 

When the slurry itself is to be fed to the atomizer or vaporizer, the duration of the previous ultrasonication step is dictated by the nature of the sample matrix. Thus, samples for the determination of As, Pb, Se and Sn in sediments by electrothermal vaporization 

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