Apr 29, 2020 · Inorganic membranes are resistant to chemical degradation from a wide range of HPLC solvents. Be aware that Teflon filters cannot be used with water due to the material’s nonpolar characteristics. HPLC mobile phase filters have a pore size of around 4.5 microns. The requirement for filtration of HPLC mobile phases is always a hotly debated topic.