Optimizing Throughput in Sterile Filtration

Over the last few weeks, Pall’s Filtration Nation blogs have introduced a series of Sterile Filtration Scientific Briefs to address some of the important but often-overlooked fundamentals of sterile filtration, and to explore some of the critical success factors that can make or break your filtration protocol. To recap, in Part 1, prefiltration was examined, Part 2 addressed sterile filtration and integrity, and Part 3 focused on differential pressure monitoring . Part 4, below, will delve into improving sterile filtration throughput.

Throughput, or filtration rate, is a key parameter that we always want to optimize for in sterile filtration. Filters by their very nature retard the flow rate of the fluid passing across them. They are almost always the bottleneck step in any process, the step that determines the overall rate of the entire process. Hence, we can improve the speed of the overall process by paying attention to the throughput of the sterile filtration step and increasing it as much as we can without risking damage to the membrane.

The trick to optimizing sterile filtration throughput is to understand a pair of often overlooked and in general, poorly understood parameters: flux and venting. The Scientific Brief, linked at the end of this blog, provides a concise guide to understanding flux and venting, detailing how to use them to make your sterile filtration process run as fast as possible. What follows is a quick introduction to both.