Costar® Spin-X® Centrifuge Tube Filters, 0.45 um Pore NY Membrane, Nonsterile, 8170, Corning (CAT#: STEM-LC-0474-Y) Nalgene ® Syringe Filter Units, Disposable, Polyethersulfone (PES) Membrane, Pore Size 0.2 μm, Diam. 13 mm, Aijiren Tech Scientific (CAT#: STEM-FC-0041-LC) MF-Millipore Membrane Filter, 0.05 µm Pore Size, 25 mm Diameter, MF