Aggregation of red blood cells in a strong electric field

ERYTHROCYTES, when suspended in blood plasma, form ‘rouleaux’, in which the single erythrocytes lie parallel like a pile of coins. This phenomenon is dependent on the presence of a specific substance in the plasma. When suspended in an isotonic sugar solution, the erythrocytes settle to the bottom very slowly, without forming any characteristically shaped aggregation. On the other hand, the same suspension of blood cells, when exposed to the influence of a powerful electric field (approximately 100 V./cm.), rapidly forms macroscopically visible aggregations of red blood cells, quickly settling to the bottom. In this way, all erythrocytes are separated from the supernatant sugar solution in a few minutes.