Experimental study on in vitro tumor cell killing by focused bi-frequency ultrasound activated hematoporphyrin derivatives.
OBJECTIVE
As ultrasound has become an important therapeutic technique on tumor, in order to find the cell-killing effect of focused bi-frequency ultrasound activated hematoporphyrin derivatives, experimental study was processed in vitro.


METHODS
Tumor cells K562 and SW-480 were killed by focused bi-frequency ultrasound activated hematoporphyrin (Hp) derivatives under optimized ultrasonic parameters and the cell-killing effect was tested by MTT (Thiazolyl blue: 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) technique.


RESULTS
The lower frequency (0.6 MHz) was better than the higher (1.1 MHz) in activating hematoporphyrin derivatives; the bi-frequency was better than mono-frequency, and the cell-killing efficiency was 2-3 times of sum of the two kinds of ultrasounds which constitute bi-frequency. Incubation for the 16 h was better than 4 h after the cells exposed to the ultrasound.


CONCLUSIONS
The method of killing tumor cells by focused bi-frequency ultrasound activated hematoporphyrin derivatives is presented and evaluated in this paper.
Shang
Z
Z
Biomedical Engineering Center, Beijing University of Technology, Beijing, China.
Ren
X
X
Zhang
J
J
Zhu
X
X
Qi
H
H
Liu
Q
Q
Zhang
K
K
Wu
S
S
Zeng
Y
Y
D017209:Apoptosis / Q000187:drug effects*; D045744:Cell Line, Tumor; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology*; D006415:Hematoporphyrins / Q000627:therapeutic use*; D006801:Humans; D020014:K562 Cells; D017319:Photosensitizing Agents / Q000627:therapeutic use; D016896:Treatment Outcome; D014464:Ultrasonic Therapy / Q000379:methods*
D006415:Hematoporphyrins; D017319:Photosensitizing Agents