Sickle cells show low expansibility and high resistance to saponin

The expansibility under hypotonic condition and the susceptibility to saponin under hypotonic and deoxygenated conditions were determined. The experiments were carried out using a conventional blood cell counter and comparable volume changes were displayed on a chart as a graphic presentation. The sickle cells showed low expansibility and strong resistance to saponin, where the resultant curve of sickle cells showed prolonged hemolysis time and characteristic volume change. Thus, the methods would be useful for detecting sickle cell disease during routine laboratory procedures.