technology

Alternating tangential flow (ATF) perfusion

A hollow-fiber filter module alternates flow direction to retain cells while continuously exchanging spent media for fresh, sustaining very high viable-cell densities in a stirred-tank format.

Where it's used

High-cell-density culture systems
Bioreactor hardware engineered to sustain far higher viable-cell densities than a conventional stirred tank — Repligen's XCell ATF perfusion system (100M+ cells/mL), PBS Biotech's Vertical-Wheel bioreactors, Univercells Technologies' scale-X fixed-bed platform, and Cellexus's CellMaker airlift bioreactors — the equipment layer that lets a fed-batch or perfusion process pack more cells and more product into the same reactor volume.
upstream-bioreactors 8 min