Whatman 6994-2504 25mm Dia, GD/PX, 0.45 micrometer Pore Size, Polyethersulfone (PES), Hydrophilic, 150/pk (PN:6994-2504)

Whatman GD/PX syringe filters are used for sample clarification and preparation before analytical testing. They help remove particulate matter from liquid samples prior to analysis in instruments such as HPLC, ion chromatography, or spectrometry, improving data reliability and protecting sensitive equipment.

The filters use polyethersulfone (PES) membranes, which provide high flow rates and very low protein binding. This makes them suitable for filtering biological solutions such as serum, plasma, and tissue culture samples while minimizing sample loss or adsorption.

The GD/PX design includes a prefiltration stack combined with a final membrane layer. The prefilter layers help capture larger particles first, reducing clogging and allowing higher sample volumes to pass through the filter compared with standard single-layer syringe filters.

A 25 mm syringe filter typically supports filtration of larger sample volumes than smaller filters, often up to about 100 mL depending on sample composition. The larger filtration area helps maintain good flow rates and reduces the likelihood of filter blockage during sample preparation.

These syringe filters are frequently used in pharmaceutical, biotechnology, environmental, food, and agricultural laboratories. They are particularly useful for inorganic ion analysis and filtration of difficult samples, as the filter design helps minimize ion extractables and improve sample purity.