Title :
The effect of ultrasound on the electrical impedance of biological cells
Author :
Kaufman, J.J. ; Popp, H. ; Chiabrera, A. ; Pilla, A.A.
Author_Institution :
Dept. of Orthopaedics, Mt. Sinai Med. Center, New York, NY, USA
Abstract :
It has been shown that low-power ultrasound (US) has a significant effect on the rate of fresh fracture healing in animals and humans. The action of US can involve a direct mechanical effect (microstrain) or an indirect electrokinetic effect. To test the electrokinetic hypothesis, a four-electrode measurement technique is used to evaluate the effects of externally applied US on cell membrane impedance. Results indicate that US significantly affects the membrane impedance in the frequency range predicted by electrochemical modeling to be relevant to specific absorption, 5-100 kHz. The action of US via an electrokinetic pathway implies the displacement of ions in the diffuse double layer via the local pressure wave. Results obtained with a chloride-ion-depleted solution showed a significant US modification of membrane impedance in a higher frequency range (50-300 kHz), which appears to confirm that the effect of US at the membrane surface is ion-dependent.<>
Keywords :
bioelectric phenomena; biological effects of acoustic radiation; cellular effects of radiation; ultrasonic effects; 4-electrode measurement technique; biological cells; diffuse double layer; electrical impedance; electrokinetic effect; fresh fracture healing rate; ions displacement; local pressure wave; low-power ultrasound; mechanical effect; membrane impedance; microstrain; ultrasound effect;
Conference_Titel :
Engineering in Medicine and Biology Society, 1988. Proceedings of the Annual International Conference of the IEEE
Conference_Location :
New Orleans, LA, USA
Print_ISBN :
0-7803-0785-2
DOI :
10.1109/IEMBS.1988.95001
