Electrokinetic Properties of Isolated Cells Exposed to Low Levels of Ultrasound

Abstract

The rapid expansion of ultrasonic diagnostic procedures in many branches of medicine has increased the need for a better understanding of the basic biophysical events. Up to now the appreciation of possible hazards has been based mainly on the findings of chromosome aberrations of sonicated cells. Recently, however, it has been suggested that chromosome-breakages may not be the most sensitive indicator of cell damage, because certain biological reactions are affected even by ultrasonic intensities used in diagnostics. Detectable effects on DNA and growth patterns of animal cells at the temporal averaged spatial peak intensity of 45.5 mWcm⁻² were demonstrated by Liebeskind et al. (1979). Pizzarello et al. (1979) have shown that mouse lymphosarcoma exhibits reduced transplantability following exposure to an average acoustic output of 1.5 mW. Cellular attachment of cultured human cells has been found to be a sensitive indicator of the ultrasound effect at an output of 1.76 mW (Siegel et al. 1979). Miller et al. (1979) have found platelet aggregation induced by ultrasound at peak intensities of 16 – 32 mWcm⁻². All these findings show that ultrasound is able to produce alteration of a sensitive biological system even at intensities below 1 kWm⁻².