It has been shown that an increase in permeability with cell membrane damage caused by cutting force and oxygen radicals occurs, and the resulting
acoustic cavitation inhibits tumor development (16).
But here is another important parameter, the acoustic intensity (W/[m.sup.2]), where the combination of ultrasound and the increase in acoustic intensity can generate two effects,
acoustic cavitation and shockwaves and modulating frequency [17].
Bubbles created by
acoustic cavitation are employed in sonochemistry and other industrial processes, such as cleaning, mixing, and water treatment [1-6].
Zhang et al., "The correlation between
acoustic cavitation and sonoporation involved in ultrasound-mediated DNA transfection with polyethylenimine (PEI) in vitro," Journal of Controlled Release, vol.
Ultrasonic degassing is among the first potential applications of
acoustic cavitation in liquids.
In particular,
acoustic cavitation involves sending sound waves in the ultrasonic frequency range (>20 kHz) through a liquid medium.
It employs the
acoustic cavitation of microbubbles to enhance delivery of these large molecules.
The extraction process was assisted by sonication which is based on the sonochemical phenomenon associated with
acoustic cavitation [11] that helps the disruption of cell walls and facilitate the release of contents [12].
This is due to the fact that ultrasonic wave energy arises from
acoustic cavitation process (
acoustic cavitation) which consists of the formation, growth, and collapse (implosive collapse) of the bubble formed.
Introducing an ultrasound to the electrolytic cell resulted in
acoustic cavitation. The creation of gas bubbles (both hydrogen and oxygen) on the electrodes accelerated, and steady bubbles were formed through direct diffusion.
Therefore, the sonochemistry arises not from a direct action of ultrasonic waves on molecules, but rather from the
acoustic cavitation. Simply put, cavitation is a set of consequent events: nucleation, growth, and violent collapse of microbubbles in liquids submitted to ultrasonic vibrations.
Application of ultrasonic wave in remediation field is derived from
acoustic cavitation: the formation, growth and implosive collapse of bubble in solution.