A method for purifying and harvesting certain cell populations in blood or bone marrow by depleting at least one of red blood cells, granulocytes, or platelets from a sample comprising blood, bone marrow, or stromal vascular fraction cells separated from adipose tissue is disclosed. The apparatus comprises a sterile, single use rigid, self-supporting cartridge within which the automated depletion, purification and harvesting of target cell populations occurs and all components may be distributed.