Sonoporation
Sonoporation, or cellular sonication, is the use of sound (typically ultrasonic frequencies) for modifying the permeability of the cell plasma membrane. This technique is usually used in molecular biology and non-viral gene therapy in order to allow uptake of large molecules such as DNA into the cell, in a cell disruption process called transfection or transformation. Sonoporation employs the acoustic cavitation of microbubbles to enhance delivery of these large molecules.[1] The bioactivity of this technique is similar to, and in some cases found superior to, electroporation. Extended exposure to low-frequency (<MHz) ultrasound has been demonstrated to result in complete cellular death (rupturing), thus cellular viability must also be accounted for when employing this technique.
Sonoporation is under active study for the introduction of foreign genes in tissue culture cells, especially mammalian cells. Sonoporation is also being studied for use in targeted Gene therapy in vivo, in a medical treatment scenario whereby a patient is given modified DNA, and an ultrasonic transducer might target this modified DNA into specific regions of the patient's body.[2]
Equipment
Sonoporation is performed with a dedicated sonoporator. Sonoporation may also be performed with custom-built piezoelectric transducers connected to bench-top function generators and acoustic amplifiers. Standard ultrasound medical devices may also be used in some applications.
Measurement of the acoustics used in sonoporation is listed in terms of mechanical index, which quantifies the likelihood that exposure to diagnostic ultrasound will produce an adverse biological effect by a non-thermal action based on pressure.[3]
Microbubble Agents
Sonoporation uses microbubbles for significantly enhancing transfection, and in some cases is required for DNA uptake.[4] These microbubble agents include Optison, manufactured by General Electric Healthcare.
References
- ^ Yizhi Song (2007). "Ultrasound-mediated DNA transfer for bacteria". Nucleic Acids Res. 35 (19): e129. doi:10.1093/nar/gkm710. PMC 2095817. PMID 17890732.
- ^ Junru Wu; Wesley Le Mars Nyborg (2006). Emerging Therapeutic Ultrasound. ISBN 978-981-256-685-0.
- ^ Charles C. Church (2005). "Frequency, pulse length, and the mechanical index". Acoustics Research Letters Online. 6 (3): 162. doi:10.1121/1.1901757.
- ^ P.A Dijkmans; Juffermans, LJ; Musters, RJ; Van Wamel, A; Ten Cate, FJ; Van Gilst, W; Visser, CA; De Jong, N; Kamp, O (2004). "Microbubbles and ultrasound: from diagnosis to therapy". European Journal of Echocardiography. 5 (4): 245–246. doi:10.1016/j.euje.2004.02.001. PMID 15219539.