( http://www.abnova.com'>http://www.abnova.com ) This procedure to isolate mononuclear cells from whole blood is based on density differences between mononuclear cells and other elements found in the blood sample. Differential migration during centrifugation results in the formation of layers containing different cell types. Mononuclear cells are at the interface between the plasma and the ficoll layer and are recovered by washing steps. More videos at Abnova http://www.abnova.com'>http://www.abnova.com