Syringe filters. Filters Syringe Filters. Available with either PP, PTFE or nylon membrane. Membranes are available in either 0,2 or 0,45 µm pore size, with the choice often made on analytical column packing size. If the column packing size is larger than 3 μm then use 0,45 μm, and if 3 μm or smaller then use 0,2 μm.