Where it fits
The PES capsule is the last barrier in an aseptic process: sterile filtration of vaccines, serum, antibiotics and water for injection before filling or entry into the sterile core. It suits small-batch lines that change product often — a single-use capsule needs no separate housing and no cleaning validation between products.
Key characteristics
The highly asymmetric structure is the point of this capsule: the open upstream layer takes the large particles and the tight downstream layer does the final retention. That buys high initial flux and long life without giving up efficiency — in practice, fewer element changes per batch.
Non-specific protein binding is very low. For vaccines and biological reagents, active substance adsorbed onto the membrane is real yield loss, and that property is often worth more than flux itself. Ratings run from pre-filtration all the way to the sterilising grade, so one medium can cover both stages and compatibility only has to be qualified once.
Choosing between options
Three PES products on this site, differing in format and level of validation:
| Product | Format | Rating range | Choose it when |
|---|---|---|---|
| Highly asymmetric PES capsule (this) | Single-use, no housing needed | 0.05 – 5 µm | Small batches and frequent product changes, to avoid cleaning validation |
| Sterilising-grade high-flow PES pleated cartridge | Cartridge, needs a housing | 0.1 / 0.2 / 0.45 µm | A sterile barrier on a fixed line needing traceable bacterial challenge documentation |
| PES microporous pleated cartridge | Cartridge, needs a housing | 0.05 – 5 µm | High-flow fine filtration and clarification where cost per element comes first |
Operation & change-out
Naturally hydrophilic — it wets out on contact with WFI or buffer with no alcohol pre-wet; just open the vent fully and purge the air before start-up. Integrity can be re-verified on site by bubble point or diffusive flow before and after use, and every unit is integrity tested before shipment.