Anti-Phycoerythrin (PE) MicroBeads are used for the indirect magnetic labeling and separation of cells or other materials labeled with a PE-conjugated primary antibody or ligand. The use of PE-conjugated primary antibodies and Anti-PE MicroBeads leads to the highest purity and recovery, even when the marker used for sorting is weakly expressed. Anti-PE MicroBeads UltraPure have been especially designed for cell separations from debris-rich biological starting materials.