Effects of oxygen tension and pH on the ultrasonic absorption properties of sickle cells.

The ultrasonic absorption of sickle cells was compared with the morphological changes in these cells are produced by varying oxygen tensions and pH. A decrease in oxygen tension caused increased sickling and an increase in the ultrasonic absorption of the blood. An increase in pH reduced the ultrasonic absorption and decreased sickling. These findings indicate that ultrasonic absorption can detect changes in the aggregation state of sickle cell hemoglobin in situ within the red cell and that the method may be used to monitor the degree of sickling under various environmental conditions.