TY - GEN
T1 - Nano-droplet-seeded sonodynamic tumor treatment with dye sensitizer
AU - Kawabata, Ken Ichi
AU - Maruoka, Takashi
AU - Asami, Rei
AU - Wada, Akihide
AU - Muragaki, Yasuteru
AU - Umemura, Shinichiro
PY - 2012/12/1
Y1 - 2012/12/1
N2 - Phase-change nano-droplet (PCND) was found to promote cavitation and aid the active oxygen generation by sonochemical agents. PCNDs, which are droplets containing superheated perfluorocarbon, were suspended in buffer solution with a dye sensitizer, Rose Bengal (RB). Samples were exposed to 1.1-MHz ultrasound with a sequence consisting of pulses for generating microbubbles and continuous waves for inducing cavitational effects. The yield of reactive oxygen species (ROS) by ultrasound exposures, measured as the increase of fluorescence intensity of a fluorescein derivative was strongly dependent on the interval of the pulses. It was found that pulse intervals shorter than 0.03 s were needed to generate ROS. Further, we found that RB works not only for generating ROS but also for inducing cavitation. Because PCNDs have been revealed to significantly reduce cavitation threshold both in vitro and in vivo, the combination of PCNDs and dye sensitizers may lead to a sonodynamic tumor treatment method with reduced ultrasound energy and improved reproducibility.
AB - Phase-change nano-droplet (PCND) was found to promote cavitation and aid the active oxygen generation by sonochemical agents. PCNDs, which are droplets containing superheated perfluorocarbon, were suspended in buffer solution with a dye sensitizer, Rose Bengal (RB). Samples were exposed to 1.1-MHz ultrasound with a sequence consisting of pulses for generating microbubbles and continuous waves for inducing cavitational effects. The yield of reactive oxygen species (ROS) by ultrasound exposures, measured as the increase of fluorescence intensity of a fluorescein derivative was strongly dependent on the interval of the pulses. It was found that pulse intervals shorter than 0.03 s were needed to generate ROS. Further, we found that RB works not only for generating ROS but also for inducing cavitation. Because PCNDs have been revealed to significantly reduce cavitation threshold both in vitro and in vivo, the combination of PCNDs and dye sensitizers may lead to a sonodynamic tumor treatment method with reduced ultrasound energy and improved reproducibility.
KW - cavitation
KW - nano droplet
KW - phase-change
KW - rose bengal
KW - sonodynamic treatment
UR - http://www.scopus.com/inward/record.url?scp=84882338201&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84882338201&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2012.0489
DO - 10.1109/ULTSYM.2012.0489
M3 - Conference contribution
AN - SCOPUS:84882338201
SN - 9781467345613
T3 - IEEE International Ultrasonics Symposium, IUS
SP - 1952
EP - 1955
BT - 2012 IEEE International Ultrasonics Symposium, IUS 2012
T2 - 2012 IEEE International Ultrasonics Symposium, IUS 2012
Y2 - 7 October 2012 through 10 October 2012
ER -