Whatman GD/XP disposables syringe filters are ideal for use with samples that require inorganic ion analysis, as levels of ion extractables are minimized. They are also an alternative choice for users requiring a filter that exhibits extremely low protein binding characteristics. GD/XP syringe filters contain a two layer prefilter stack comprised of 20 ¬µm and 5 ¬µm polypropylene filters. The last stage of filtration is a choice of membrane, which is positioned below the prefilter stack. Ideal for HPLC sample preparation or trace metal analysis.