title: Ultrasound-directed drug delivery.
abstract: It has been proven, that the cellular uptake of drugs and genes is increased, when the region of interest is under ultrasound insonification, and even more when a contrast agent is present. This increased uptake has been attributed to the formation of transient porosities in the cell membrane, which are big enough for the transport of drugs into the cell (sonoporation). Owing to this technique, new ultrasound contrast agents that incorporate a therapeutic compound have become of interest. Combining ultrasound contrast agents with therapeutic substances, such a chemotherapeutics and virus vectors, may lead to a simple and economic method to instantly cure upon diagnosis, using conventional ultrasound scanners. There are two hypotheses for explaining the sonoporation phenomenon, the first being microbubble oscillations near a cell membrane, the second being microbubble jetting through the cell membrane. Based on modeling, high-speed photography, and recent cellular uptake measurements, it is concluded that microbubble jetting behavior is less likely to be the dominant sonoporation mechanism. Ultrasound-directed drug delivery using microbubbles is a promising method that has great potential in the treatment of malignant disorders.
authors.affiliation: Department of Engineering, The University of Hull, Kingston Upon Hull, HU6 7RX, UK. m.postema@hull.ac.uk
authors.forename: Michiel
authors.initials: M
authors.lastname: Postema
authors.forename: Odd Helge
authors.initials: OH
authors.lastname: Gilja
mesh_terms: D003287:Contrast Media / Q000008:administration & dosage; D004247:DNA / Q000008:administration & dosage*; D016503:Drug Delivery Systems / Q000379:methods*; D045423:Microbubbles; D004364:Pharmaceutical Preparations / Q000008:administration & dosage*; D014465:Ultrasonics
chemical_list: D003287:Contrast Media; D004364:Pharmaceutical Preparations; D004247:DNA