Whatman^® GD/X syringe filters 

The GD/X filter contains a unique prefiltration stack of 100% borosilicate glass. The prefilter will retain fine particles down to 0.7 μm, allowing difficult sample filtration with less hand force. The volume of the sample filtered is 3 - 7 times greater than an unprotected membrane. PP housing. Syringe filters can be autoclaved.
Membranes:
Cellulose Acetate: for biological solutions, high-loading capacity, and low-protein-binding
Nylon: for aqueous and aqueous organics
Polyethersulfone: for serum, plasma, and tissue culture solutions
Polypropylene: high flow for aqueous and organics
Polysulfone: low-protein-adsorption for serums and plasma
PTFE: chemically inert, will stop aqueous aerosols in gas streams
PVDF: the most suitable membrane for HPLC
Glass microfiber: borosilicate with high-load capacity

Whatman is a registered trademark of Whatman International Ltd.