Whatman Polycap AS (aqueous solutions) capsule filters from Cytiva combines a glass microfiber (GMF) prefilter over a nylon membrane final filter to provide maximum filtration of difficult, particulate-laden solutions. First layer (GMF) acts as a prefilter to ensure longer membrane (0.2, 0.45, and 1.0 µm) life and higher filtration efficiency. Nylon membrane filter layer is inherently hydrophilic, has low extractables, is biosafe, and has excellent flow rates Polypropylene housing is thermally fused (no glues, adhesives, or extraneous materials), reducing extractable levels Can be tested with bubble point, pressure decay, or forward flow methods Available in presterilized and nonsterile (autoclavable) versions Manufactured according to ISO9001:2008 QMS standards Recyclable after use. Learn how you can recycle it. Whatman capsule filters from Cytiva's business are available for a variety of applications. Browse the Polycap line to find the filter that matches your needs. Polycap AS for aqueous solutions Polycap AS are Whatman capsule filters specifically designed for high-volume filtration of aqueous sample solutions in a compact size. With a nylon membrane filter and GMF prefilter, these filters have a long usable life.