- Sonication
Sonication is the act of applying sound (usually
ultrasound ) energy to agitate particles in a sample, for various purposes. In the laboratory, it is usually applied using an "ultrasonic bath" or an "ultrasonic probe", colloquially known as a sonicator. In a paper machine, anultrasonic foil can distribute cellulose fibres more uniformly and strengthen the paper.Sonication can be used to speed dissolution, by breaking intermolecular interactions. It is especially useful when it is not possible to stir the sample, as with
NMR tube s. It may also be used to provide the energy for certain chemical reactions to proceed. Sonication can be used to remove dissolved gases from liquids (degassing ) by sonicating the liquid while it is under a vacuum. This is an alternative to the freeze-pump-thaw andsparging methods.In biological applications, sonication may be sufficient to disrupt or deactivate a biological material. For example, sonication is often used to disrupt cell membranes and release cellular contents.
Sonication can also be used to initiate crystallisation processes and even control polymorphic crystallisations. Sonication be used to intervene in anti-solvent precipitations (crystallisation) to aid mixing and isolate small crystals.
Sonication can also loosen particles adhering to the wall of a vessel. Therefore it can be used as a cleaning step, easier than scraping them off with a
spatula . Outside the field of laboratory science, sonicating baths are used to clean objects such asspectacles andjewelry .
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