Applications And Benefits Of Polyethylene Membrane Filters

A Q&A With Kenneth J Renfrew, MS., MBA, VP, ZenPure America's Inc.

For sterile air and gas filtration, hydrophobic PVDF membrane was the pharmaceutical engineers' historical filter membrane of choice. Then PTFE became a reliable option offering higher flow rates and greater voids volume within the matrix of the membrane. PTFE also had higher temperature tolerance, meaning it worked great for hot air filtered in huge volumes into large fermenters used to produce antibiotics like erythromycin. However, biotech moved from mini replication of bulk fermentation (small PTFE steam sterilized filters) to single-use filters. Disposable filters are hooked up to other equipment that is not easily sterilized by steam. So, instead of being steam sterilized, disposables are often gamma irradiated. This posed a problem, since PTFE is not gamma compatible. So, manufacturers turned again to PVDF.

However, there is now an alternative that is disposable, gamma stable, and meets industry sterilizing grade filter requirements — the polyethylene PE membrane filter. To find out more about this technology, we turned to ZenPure's Ken Renfrew, who has worked with microporous filtration technologies in the biotechnology, pharmaceutical, medical device and other life science spaces for more than 20 years. During his career, he has worked closely with engineers and scientists in bioprocess and product development.

In this interview, Renfrew discusses the applications and benefits of the polyethylene membrane filters. He also highlights FDA expectations for filtration technology and what filtration manufacturers need to pursue in order to keep up with future trends.