Ultrasonic absorption in the human breast cyst liquids

The ultrasonic absorption of samples of cyst liquids (CL) of the human breast has been measured as a function of frequency (1.67–115 MHz), pH (1–13), dilution and temperature (25 and 37°C). The absorption behavior of these liquids is very similar to that of protein solutions. It is shown that the absorption of CL at physiological pH arises essentially from the protein contained in these liquids and, in fact, can be evaluated to within a factor 1.5, from that of serum albumin in similar condition. The origin of this absorption is discussed.