TY - GEN
T1 - Chemo-thermal approach for efficient ultrasonic tumor treatment with phase change nano droplet
AU - Kawabata, Kenichi
AU - Asami, Rei
AU - Umemura, Shinichiro
PY - 2011/12/1
Y1 - 2011/12/1
N2 - Phase-change nano-droplet (PCND) was found to promote chemically significant cavitation. PCNDs, which were droplets containing superheated perfluorocarbon and suspended in buffer solution with potassium iodide, were exposed to 1.1-MHz ultrasound with a sequence of periodically applied triggering pulses to generate microbubbles and following continuous-wave (CW) exposures. The chemical activity of ultrasound exposures, measured as the reaction yield of tri-iodide ions was strongly dependent on the interval of the pulses. We found that pulse intervals shorter than 0.03 s were needed to generate chemically significant cavitation. Further, we found that pre-exposure of ultrasound for chemical effects could be performed by using gel phantoms with thermal coagulation indicators, without sacrificing the effect of PCNDs to enhance temperature increase induced by exposure to high intensity focused ultrasound (HIFU). The results we obtained suggested the potential of 'chemo-thermal' therapy for tumors, which sequentially utilizes the chemical and thermal effect of PCNDs.
AB - Phase-change nano-droplet (PCND) was found to promote chemically significant cavitation. PCNDs, which were droplets containing superheated perfluorocarbon and suspended in buffer solution with potassium iodide, were exposed to 1.1-MHz ultrasound with a sequence of periodically applied triggering pulses to generate microbubbles and following continuous-wave (CW) exposures. The chemical activity of ultrasound exposures, measured as the reaction yield of tri-iodide ions was strongly dependent on the interval of the pulses. We found that pulse intervals shorter than 0.03 s were needed to generate chemically significant cavitation. Further, we found that pre-exposure of ultrasound for chemical effects could be performed by using gel phantoms with thermal coagulation indicators, without sacrificing the effect of PCNDs to enhance temperature increase induced by exposure to high intensity focused ultrasound (HIFU). The results we obtained suggested the potential of 'chemo-thermal' therapy for tumors, which sequentially utilizes the chemical and thermal effect of PCNDs.
KW - cavitation
KW - chemical effects
KW - microbubble
KW - nano droplet
KW - phase-change
UR - http://www.scopus.com/inward/record.url?scp=84869033873&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84869033873&partnerID=8YFLogxK
U2 - 10.1109/ULTSYM.2011.0003
DO - 10.1109/ULTSYM.2011.0003
M3 - Conference contribution
AN - SCOPUS:84869033873
SN - 9781457712531
T3 - IEEE International Ultrasonics Symposium, IUS
SP - 9
EP - 12
BT - 2011 IEEE International Ultrasonics Symposium, IUS 2011
T2 - 2011 IEEE International Ultrasonics Symposium, IUS 2011
Y2 - 18 October 2011 through 21 October 2011
ER -