ALDEFLUORâ„¢ Assay Buffer can be used when counterstaining ALDEFLUORâ„¢-reacted cells with immunofluorescently-labeled antibodies. The buffer is necessary to maintain ALDEFLUORâ„¢ reaction product inside the cell, allowing detection of the ALDH-bright population. While there is sufficient ALDEFLUORâ„¢-buffer contained within the ALDEFLUORâ„¢ kit, additional buffer may be required for certain immunolabeling procedures.