Abstract: The present invention provides a filtration medium comprising an ultrafiltration membrane and a monomer surface coating thereon of an acrylic or methacrylic acid monomer having alcohol functional groups, wherein the filtration medium after having been fully dried is characterized by having a titer reduction of at least about 10.sup.3 with respect to PP7 bacteriophage and a critical wetting surface tension of at least about 70 mN/m. The filtration medium preferably further comprises a fibrous nonwoven web embedded in the membrane. The present invention also provides a method of filtering a fluid through the present inventive filtration medium, as well as a method of preparing such a filtration medium.

Abstract: The present invention provides for the first time ultrafiltration/diafiltration membranes that are capable of excluding 0.02 .mu.m diameter, monodisperse, latex particles and are capable of being dried without loss of such ultrafiltration properties. A rapid, reliable method for integrity testing membranes also has now been discovered. The test has particular applicability to ultrafiltration membranes, although it may also be used for testing microfiltration membranes as well. In accordance with the method, referred to as the K.sub.

Abstract: The present invention provides for the first time ultrafiltration/diafiltration membranes that are capable of excluding 0.02 .mu.m diameter, monodisperse, latex particles and are capable of being dried without loss of such ultrafiltration properties. A rapid, reliable method for integrity testing membranes also has now been discovered. The test has particular applicability to ultrafiltration membranes, although it may also be used for testing microfiltration membranes as well. In accordance with the method, referred to as the K.sub.