Whatman PTFE membranes are chemically stable and inert. They are suitable for applications involving aggressive organic solvents, strong acids and alkalis. PTFE membranes are particularly suitable for preparing samples for HPLC analysis. The hydrophobic nature of the membrane also has applications for air and gas sterilisation. The membrane is laminated onto a non-woven PP support web for improved strength and handling and can be used at temperatures up to 120 ºC.