HetaSep™ is an erythrocyte aggregation agent used to quickly separate nucleated cells from red blood cells (RBCs) in whole blood. Aggregated erythrocytes settle much faster than dispersed cells. By controlling the settling time and/or centrifugation speed, the majority of nucleated cells are recovered in the supernatant. Approximately 95 - 99% RBC depletion is attained if the nucleated cell-rich fraction is removed carefully. HetaSep™ contains 6% w/v hetastarch.