The Vacutainer CPT Mononuclear Cell Preparation Tube is for the one step isolation of lymphocytes, monocytes, and plasma. Whole blood is collected and processed in a closed, sterile tube. During centrifugation a gel barrier isolates the mononuclear cells and plasma from the erythrocytes and granulocytes. The Vacutainer CPT Tube may be used to obtain highly concentrated mononuclear cells and/or plasma for immunotyping, culture, and cell function studies, and for tests using gene-amplification techniques. In addition, the mononuclear cells may be resuspended in the plasma to retain viability for storage and transportation.