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Traditionally a diagnostic modality, ultrasound is emerging as a promising tool for non-invasive therapy, drug
delivery, and gene therapy. The ultrasound is a mechanical wave energy generated in a medium as oscillating
pressure in space and time at frequencies above 20 kHz, beyond the audible range. The ultrasound exposure generates bioeffects resulting in tissue heating, shear stress, and cavitation, which have been exploited for therapeutic
applications. Ultrasound cavitation, enhanced by injected micro bubbles, perturbs cell membrane structures to
cause sonoporation and increases the permeability to bioactive materials. Ultrasound-mediated gene delivery has
been applied to heart, blood vessel, lung, kidney, muscle, head and neck tumour with enhanced gene transfection
efficiency. The genes can be incorporated into microbubbles which in turn can target a specific disease site. Local
drug delivery ensures sufficient drug concentration at the diseased region while limiting toxicity for healthy tissues. Nevertheless, it has only recently become popular as a technique to enhance drug release from drug delivery
systems. This review presents the main findings in the field of sonoporation, namely drug delivery, gene delivery
and DNA transfer.
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